Guide to Estimating Irrigation Water Needs of Landscape Plantings

A Guide 

to 

Estimating Irrigation Water Needs 

of 

Landscape Plantings 

in 

California 

The Landscape Coefficient Method 

and 

WUCOLS III 

University of California Cooperative Extension 

California Department of Water Resources

Cover photo: The Garden at Heather Farms, Walnut Creek, CA 

This Guide is a free publication. Additional copies may 

be obtained from: 

Department of Water Resources 

Bulletins and Reports 

P. O. Box 942836 

Sacramento, California 94236-0001 

(916) 653-1097 

Photography: L.R. Costello and K.S. Jones, University of California Cooperative Extension 

Publication Design: A.S. Dyer, California Department of Water Resources

A Guide 

to 

Estimating Irrigation Water Needs 

of 

Landscape Plantings 

in 

California 


and 

WUCOLS III* 

*WUCOLS is the acronym for Water Use Classifications of Landscape Species. 


California Department of Water Resources 

August 2000

Preface 

This Guide consists of two parts, each formerly a 

separate publication: 

Part 1—Estimating the Irrigation Water Needs of 

Landscape Plantings in California: The Landscape 

Coefficient Method 

• L.R. Costello, University of California Cooperative 

Extension 

• N.P. Matheny, HortScience, Inc., Pleasanton, CA 

• J.R. Clark, HortScience Inc., Pleasanton, CA 

Part 1 describes a method for calculating landscape 

water needs, while Part 2 gives evaluations of water 

needs for individual species. Used together, they 

provide the information needed to estimate irrigation 

water needs of landscape plantings. 

Part 1 is a revision of Estimating Water Requirements 

of Landscape Plants: The Landscape Coefficient 

Method, 1991 (University of California 

ANR Leaflet No. 21493). Information presented in 

the original publication has been updated and expanded. 

Part 2—WUCOLS III (Water Use Classification 

of Landscape Species) 

• L.R. Costello, University of California Cooperative 

Extension 

• K.S. Jones, University of California Cooperative 

Extension 

Part 2 represents the work of many individuals and 

was initiated and supported by the California Department 

of Water Resources. This third revision 

(WUCOLS III) includes many species not previously 

evaluated, as well as an update and reorganization 

of support information. 

These two publications are companion documents 

and are intended to be used together. 

First-time readers are encouraged 

to carefully review both 

parts of this Guide before making 

estimates of landscape water 

needs. 

Eschscholzia california, California poppy 

iii

Contents 

Part 1—The Landscape Coefficient 

Part 2—WUCOLS III ..................................... 

45 

Method ............................................................ 

1 

Project Participants ........................................... 

46 

Introduction ...................................................... 

3 

Introduction ...................................................... 

49 

Chapter 1—Estimating Water 

Requirements for Crops and Turf ..................... 

5 

Getting Started .................................................. 

51 

Categories of Water Needs ......................... 

52 

Chapter 2—Estimating Water Needs for 

Standard Conditions ................................... 

53 

Landscape Plantings ......................................... 

9 

Plant Types ................................................. 

55 

Regions ....................................................... 

56 

Chapter 3—Using the Landscape 

Coefficient Formula .......................................... 

23 

Other Important Information About the 

Guide ............................................................. 

59 

Chapter 4—Using the Landscape 

Species Evaluations ................................ 

62 

Coefficient to Estimate Landscape 

Key to Symbols ....................................... 

62 

Evapotranspiration ........................................... 

27 

Species Evaluation List—1999 .................. 

63 

Common Names Index ........................... 

101 

Chapter 5—Irrigation Efficiency and 

Turfgrasses .............................................. 

137 

Calculating the Total Amount of Water to 

Apply ................................................................ 

29 

Appendices 

Chapter 6—Putting it all Together: A 

A—Reference Evapotranspiration Values for 

Worksheet for Calculations .............................. 

33 

Selected Locations in California ............ 

139 

B—Invasive Species ...................................... 

143 

Chapter 7—Using Water Estimates in 

C—Glossary .................................................. 

145 

Landscape Planning and Management ............. 

37 

D—Additional Resources .............................. 

147 

Chapter 8—Special Planting Situations .......... 

39 

v

Part 1 


The Landscape Coefficient Method (LCM) describes a method of estimating irrigation needs of 

landscape plantings in California. It is intended as a guide for landscape professionals. It includes 

information that is based on research and on field experience (observation). Readers are advised that 

LCM calculations give estimates of water needs, not exact values, and adjustments to irrigation 

amounts may be needed in the field. 

L. R. Costello, Environmental Horticulture Advisor 


N. P. Matheny, Horticultural Consultant 

HortScience, Inc. 

J. R. Clark, Horticultural Consultant 

HortScience, Inc. 

1

Introduction 

Part 1 leads you through the concepts, terms, and 

formulas needed to estimate irrigation water needs. 

You will learn: 

• the key formulas needed for calculations, 

• the principal concepts that serve as a basis for calculations, 

• how to use the methods in the field, 

• how to use estimates in irrigation planning and 

management, 

• where to find important numbers in reference 

tables, and 

• considerations for special landscape situations. 

Audience 

All landscape professionals involved in the planning, 

installation, and maintenance of irrigated landscapes 

should find this information of value. This 

includes architects, planners, contractors, park managers, 

gardeners, consultants, water suppliers, auditors, 

and students. 

Importance 

Estimates of landscape water needs are important 

for at least three reasons: 

1. Water Conservation. Water is a limited natural 

resource. Efficient water use in urban landscapes 

contributes substantially to the conservation of 

this resource. Water use efficiency can be 

achieved by supplying only the amount of water 

sufficient to meet plant needs. 

Chapters 

After providing background information on estimating 

water needs for agricultural crops and turf in 

Chapter 1, landscape needs are addressed in Chapter 

2. The landscape coefficient, a key factor in 

the formula for estimating landscape water requirements, 

is introduced in Chapter 2. Subsequent chapters 

give examples of how to calculate and use the 

landscape coefficient. Chapter 5 addresses irrigation 

efficiency and gives examples of how it is used 

to determine total water needs. As a way of “putting 

it all together,” a worksheet which summarizes 

the process is provided in Chapter 6. Special topics 

are discussed in Chapters 7 and 8. The appendices 

provide further information. 

Applying only the amount of water landscape plants need to remain 

healthy and attractive is an efficient use of a natural resource. 

3

2. Economics. Water costs continue to increase. 

By applying only that amount of water needed 

by landscapes, and avoiding excess use, money 

can be saved. 

3. Landscape Quality. The potential for plant injury 

caused by water deficits or excess can be 

minimized by identifying and meeting plant 

needs. 

Getting Started 

First-time readers are encouraged to review the entire 

Guide prior to making water needs estimates. 

Field examples and a practice worksheet in Chapter 

6 show how to use the information presented in previous 

chapters. Be sure to review the appendices; 

they contain important numbers for calculations. 

Formulas and Numbers 

Formulas and numbers are needed to calculate irrigation 

water requirements. Fortunately, the calculations 

needed here are simple and straightforward. 

They require only a basic understanding of mathematics. 

Once you have reviewed the examples and 

made some calculations on your own, you should 

have no difficulty. A worksheet with all the formulas 

and sample calculations is included in Chapter 6. 

4

Chapter 1— 

Estimating Water 

Requirements 

for Crops and Turf 

Water requirements of many agricultural crops have been established 

(see Table1). 

In agriculture, irrigation water requirements are well 

established for many crops. In urban landscapes, 

irrigation requirements have been determined for 

turfgrasses, but not for most landscape species. This 

chapter discusses the method used to estimate water 

requirements for agricultural crops and 

turfgrasses. Chapter 2 adapts this method for application 

to landscape plantings. 

Water requirements for agricultural crops and 

turfgrasses have been established in laboratory and 

field studies by measuring plant water loss (evapotranspiration). 

The total amount of water lost during 

a specific period of time gives an estimate of 

the amount needed to be replaced by irrigation. 

Since growers and turf managers are not equipped 

to measure plant water loss in the field, a formula 

was developed which allows water loss to be calculated. 

This formula (referred to as the ETc formula) 

is written as follows: 

ETc = Kc x ETo 

Crop Evapotranspiration = 

Crop Coefficient x Reference Evapotranspiration 

This formula states that water loss from a crop (crop 

evapotranspiration, ETc) equals the amount of water 

that evaporates from a 4- to 7-inch tall cool season 

grass growing in an open-field condition (reference 

evapotranspiration, ETo) multiplied by a factor 

determined for the crop (crop coefficient, Kc). 

Reference evapotranspiration (ETo) is estimated 

from a Class A evaporation pan or from a specialized 

weather station. Normal year (historical) average 

values for many locations in California are 

found in Appendix A. Current daily ETo values are 

available from the California Irrigation Management 

Information System (CIMIS) and can be accessed 

via the Internet (www.cimis.water.ca.gov) or by contacting 

the California Department of Water Resources 

(see Appendix D). 

Water requirements of both cool and warm season turfgrasses have 

been established (see Table 1). 

5

less than 1.0. For example, if water loss from corn 

was measured to be 4 inches in a month, and reference 

evapotranspiration for the same month was 

8 inches, then the crop coefficient would be 0.5. 

Crop coefficients have been established for many 

crops and for turfgrasses. A sample of values is 

given in Table 1. 

Table 1— 

Crop Coefficients for Various Crops and 

Turfgrasses 

Kc values for agricultural crops typically change during the seasons: 

low values are for early season (March/April) or late season (September/October) 

and high values for midseason (May/June/July). 

Kc values 

Low High 

Deciduous orchard* 0.50 0.97 

Deciduous orchard with 

cover crop** 0.98 1.27 

Grape 0.06 0.80 

Olive 0.58 0.80 

Pistachio 0.04 1.12 

Citrus 0.65 year-round 

A specialized weather station (CIMIS station) or a Class A evaporation 

pan (background) can be used to determine reference evapotranspiration 

(ETo) for a site. Daily CIMIS data is available online at 

www.cimis. water.ca.gov. 

The crop coefficient (Kc) is determined from field 

research. Water loss from a crop is measured over 

an extended period of time. Water loss and estimated 

reference evapotranspiration are used to calculate 

Kc as follows: 

Kc = ETc 

ETo 

As seen in the above equation, the crop coefficient 

(Kc) is simply the fraction of water lost from the 

crop relative to reference evapotranspiration. Typically, 

crop water loss is less than reference evapotranspiration 

and, therefore, the crop coefficient is 

Turfgrass 

Cool season species 0.8 year-round 

Warm season species 0.6 year-round 

Source: UC Leaflet Nos. 21427 and 21428 (see references) 

* Deciduous orchard includes apples, cherries, and walnuts 

** When an active cover crop is present, Kc may increase by 25 to 

80%. 

In summary, an estimate of crop evapotranspiration 

is made from reference evapotranspiration and crop 

coefficient values. Estimates can be made for any 

location where reference evapotranspiration data 

exists and for any crop (or turfgrass) that has a crop 

coefficient. 

Example: A grape grower in Monterey County 

wants to estimate how much water the vineyard may 

lose in the month of July. Using the ETc formula, 

two numbers are needed: reference evapotranspi- 

6

ation (ETo) for July in Monterey and the crop coefficient 

(Kc) for grapes. July ETo for Monterey can 

be found in Appendix A, and the Kc for grapes is 

listed in Table 1 (above). With the two values, the 

following computation is made: 

ETo = 0.18 inches per day x 31 days = 5.58 

inches (average for July in Monterey) 

Kc = 0.8 (midseason value for grapes) 

ETc = 

ETc = 

Kc x ETo 

0.8 x 5.58 = 4.46 inches 

The grower has estimated that 4.46 inches of water 

will be lost from the vineyard (via evapotranspiration) 

in the month of July. By using this ETc estimate, 

the grower can calculate irrigation water requirements 

for the vineyard. (For an estimate of 

the total amount of water to apply, see Chapter 5). 

The ETc formula is the key formula for estimating 

water loss from crops and turfgrasses. A version of 

this formula will be used in Chapter 2 to estimate 

water loss for landscape plantings. It is recommended 

that you become familiar with the ETc formula 

before continuing. 

7

Chapter 2— 

Estimating Water 

Needs for Landscape 

Plantings 

Two formulas are used to estimate water needs for 

landscape plantings: 

• the landscape evapotranspiration formula and 

• the landscape coefficient formula. 

Both formulas are introduced here and then used in 

subsequent chapters to estimate water needs. The 

landscape coefficient was developed specifically for 

estimating landscape water needs and is the principal 

focus of Chapter 2. 

The method used for estimating water needs for landscape 

plantings is basically the same as that used 

for crops and turfgrasses. The ETc formula discussed 

in Chapter 1 is simply modified for application to 

landscapes. One key change, however, has been 

made: instead of using the crop coefficient (Kc), a 

landscape coefficient (KL) has been substituted. 

The Landscape Evapotranspiration 

Formula 

Water needs of landscape plantings can be estimated 

using the landscape evapotranspiration formula: 

ETL = KL x ETo 

Landscape Evapotranspiration = 

Landscape Coefficient x Reference Evapotranspiration 

This formula (called the ETL formula) states that 

water needs of a landscape planting (landscape 

evapotranspiration, ETL) is calculated by multiplying 

the landscape coefficient (KL) and the reference 

evapotranspiration (ETo). 

As mentioned above, the ETL formula is basically 

the same as the ETc formula from Chapter 1, except 

that a landscape coefficient (KL) has been substituted 

for the crop coefficient (Kc). This change is 

necessary because of important differences which 

exist between crop or turfgrass systems and landscape 

plantings (see “Why a Landscape Coefficient”). 

The following is an example of a simple calculation 

using the landscape coefficient in the landscape 

evapotranspiration (ETL) formula. 

Example: A landscape architect wants to estimate 

water loss for the month of August from a large 

groundcover area being considered for a new commercial 

office park in Fresno. The architect looked 

up the reference evapotranspiration for August in 

Fresno (Appendix A) and found it to be 7.1 inches. 

The architect assigned a landscape coefficient value 

of 0.2. Using this information and the landscape 

evapotranspiration formula (ETL formula), the architect 

makes the following calculations: 

KL = 0.2 

ETo = 7.1 inches for August in Fresno 


ETL = 0.2 x 7.1 = 1.42 inches 

The architect estimates that the groundcover will 

need 1.4 inches in the month of August. (This is 

not the total amount of irrigation water needed, however, 

as irrigation efficiency needs to be considered. 

This topic is addressed in Chapter 5.) 

9

In this example, a landscape coefficient was assigned. 

In actual practice, KL needs to be calculated. 

The formula needed to calculate KL is the 

heart of the landscape coefficient method and is the 

subject of the next discussion. 

The Landscape Coefficient Formula 

As the name implies, the landscape coefficient was 

derived specifically to estimate water loss from landscape 

plantings. It has the same function as the crop 

coefficient, but is not determined in the same way. 

Landscape coefficients are calculated from three factors: 

species, density, and microclimate. These factors 

are used in the landscape coefficient formula as 

follows: 

KL = ks x kd x kmc 

Landscape Coefficient = 

species factor x density factor x microclimate factor 

This formula (called the KL formula) states that the 

landscape coefficient is the product of a species factor 

multiplied by a density factor and a microclimate 

factor. By assigning numeric values to each 

factor, a value for KL can be determined. The landscape 

coefficient is then used in the ETL formula, 

just as the crop coefficient is used in the ETc formula. 

Why a Landscape Coefficient? 

Crop coefficients are used for agricultural crops and 

turfgrasses, so why not for landscape plantings? 

There are three key reasons why landscape coefficients 

are needed instead. 

1. Unlike a crop or turfgrass, landscape plantings 

are typically composed of more than one species. 

Collections of species are commonly irrigated 

within a single irrigation zone, and the dif- 

ET Rates and Plant Water Needs 

Soil water availability plays a major role in controlling the rate of water loss from plants (ET rate). Many plants 

will lose water at a maximum rate as long as it is available. For example, some desert species have been found 

to maintain ET rates equivalent to temperate zone 

species when water is available. When soil moisture 

levels decrease, however, ET rates in desert 

species decline rapidly. 

In landscape management, it is not the objective 

to supply all the water needed to maintain maximum 

ET rates. Rather, it is the intent to supply 

only a sufficient amount of water to maintain 

health, appearance and reasonable growth. Maximum 

ET rates are not required to do this. 

The ETL formula calculates the amount of water 

needed for health, appearance and growth, not 

the maximum amount that can be lost via evapotranspiration. 

Some desert species, such as mesquite (Prosopis glandulosa 

torreyana), have been found to maintain ET rates equivalent to 

temperate zone species when water is available (Levitt et al 1995). 

When soil moisture levels decrease, however, ET rates in desert 

species decline rapidly. 

10

greater amount of water than a 

sparse planting. To produce a 

reliable estimate of water loss, 

a coefficient for landscapes 

needs to account for such variation 

in vegetation density. 

Unlike agricultural crops or turfgrass, landscape plantings are typically composed of many 

species. Collections of species are commonly irrigated within a single irrigation zone, and the 

different species within the irrigation zone may have widely different water needs. Using a crop 

coefficient for one species may not be appropriate for the other species. 

ferent species within the irrigation zone may 

have widely different water needs. For example, 

a zone may be composed of hydrangea, rhododendron, 

alder, juniper, oleander, and olive. 

These species are commonly regarded as having 

quite different water needs and the selection 

of a crop coefficient appropriate for one species 

may not be appropriate for the other species. 

Crop coefficients suitable for landscapes need 

to include some consideration of the mixtures 

of species which occur in many plantings. 

2. Vegetation density varies considerably in landscapes. 

Some plantings have many times more 

leaf area than others. For example, a landscape 

with trees, shrubs, and groundcover plants 

closely grouped into a small area will have much 

more leaf area than one with only widely spaced 

shrubs in the same-sized area. More leaf area 

typically means an increase in evapotranspiration 

(water loss) for the planting. As a result, a 

dense planting would be expected to lose a 

3. Many landscapes include a 

range of microclimates, from 

cool, shaded, protected areas to 

hot, sunny, windy areas. These 

variations in climate significantly 

affect plant water loss. 

Experiments in Seattle, Washington, 

found that a planting in 

a paved area can have 50% 

greater water loss than a planting of the same 

species in a park setting. Other studies in California 

found that plants in shaded areas lost 50% 

less water than plants of the same species in an 

open field condition. This variation in water loss 

caused by microclimate needs to be accounted 

for in a coefficient used for landscape plantings. 

Collectively, these factors make landscape plantings 

quite different from agricultural crops and 

turfgrasses, and they need to be taken into account 

when making water loss estimates for landscapes. 

The landscape coefficient was developed specifically 

to account for these differences. 

11

The Landscape Coefficient Factors: 

Species, Density, and Microclimate 

Three factors are used to determine the landscape 

coefficient: 

• Species 

• Density 

• Microclimate 

These factors are key elements of the landscape coefficient 

method and need to be understood fully 

before KL and ETL calculations are made. As well 

as describing each factor, the following sections give 

information on how to assign values to each. 

Species Factor (ks) 

The species factor (ks) is used to account for differences 

in species’ water needs. In established landscapes, 

certain species are known to require relatively 

large amounts of water to maintain health and 

appearance (e.g., cherry, birch, alder, hydrangea, 

rhododendron), while others are known to need very 

little water (e.g., olive, oleander, hopseed, juniper). 

This range in water needs is accounted for in the 

species factor. 

Species factors range from 0.1 to 0.9 and are divided 

into four categories: 

Very low < 0.1 

Low 0.1 - 0.3 

Moderate 0.4 - 0.6 

High 0.7 - 0.9 

These species factor ranges apply regardless of vegetation 

type (tree, shrub, groundcover, vine, or herbaceous) 

and are based on water use studies for landscape 

species (Table 2) and applicable data from 

agricultural crops (Table 1). 

An evaluation of plant water needs (based on field 

observations) has been completed for over 1,800 

species. These values are presented in Part 2 

(WUCOLS III). Species factor values can be found 

by looking up the species under consideration, and 

selecting an appropriate value from the category 

Water: Needed for What? 

In agricultural systems, water is applied to produce 

a crop. Whether it be tomatoes, beans, or 

apples, growers apply water to optimize yield and 

quality. In landscape systems, health, appearance, 

and growth are of greatest interest. Irrigation 

is managed to sustain plant defense systems, 

achieve desired canopy densities and color, generate 

desired growth, and produce flowers and 

fruit (in some species). Irrigation is not used to 

produce a harvestable crop in landscapes. Because 

of this difference between landscape and 

agricultural systems, landscapes typically can be 

managed at a level of irrigation lower than that 

needed for crop production. 

12

ange. The following is an example 

of using the WUCOLS 

list to select an appropriate ks 

value. 

Example: A landscape manager 

in Pasadena is attempting 

to determine the water requirements 

of a large planting of Algerian 

ivy. In using the ETL formula, 

the manager realizes a 

value for the species factor (ks) 

is needed in order to calculate 

the landscape coefficient (KL). 

Using the WUCOLS list 

(Part 2), the manager looks up 

Algerian ivy (Hedera canariensis) and finds it classified 

as “moderate” for the Pasadena area, which 

means that the value ranges from 0.4 to 0.6. Based 

on previous experience irrigating this species, a low 

range value of 0.4 for ks is chosen and entered in the 

KL formula. (If the manager had little or no experience 

with the species, a middle range value of 0.5 

would be selected.) 

Certain species, such as tree ferns (Dicksonia antarctica and Cyathea cooperi), require relatively 

large amounts of water to maintain health and appearance. 

Although the above example is straightforward, the 

assignment of species factors to plantings can be 

difficult. Refer to “Assigning Species Factors to 

Plantings” for guidance in making ks assignments. 

Some species, such as flannel bush 

(Fremontodendron spp.), need very 

little irrigation water to maintain 

health and appearance. 

13

Table 2— 

Irrigation Needs of Well-Established Landscape 

Species Determined from Field Research 

Values are given as the minimum fraction of reference evapotranspiration 

needed to maintain acceptable appearance, health, and reasonable 

growth for the species. See Appendix D for complete references. 

Plant Species 

Fraction of ETo 

Potentilla tabernaemontani 0.5 - 0.75 

Sedum acre 0.25 

Cerastium tomentosum 0.25 

Liquidambar styraciflua 0.20 

Quercus ilex 0.20 

Ficus microcarpa nitida 0.20 

Hedera helix ‘Neddlepoint’ 0.20 

Drosanthemum hispidum 0.20 

Gazania hybrida 0.25-0.50 

Vinca major 0.30 

Baccharis pilularis 0.20 

Reference: Staats and Klett; Hartin, et al; Pittenger, et al 

species are assigned and choose the appropriate 

value. For example, if all the species are in the 

moderate category, then a value from 0.4 to 0.6 

is selected. 

b. When species water needs are not similar: In 

cases where species with different water needs 

are planted in the same irrigation zone, then the 

species in the highest water-need category determine 

the ks value. This assignment is required 

if all plants are to be retained without water stress 

injury. For example, if species in low, moderate, 

and high categories are planted in the same 

irrigation zone, then to avoid water stress injury 

to species in the high category, a ks value from 

0.7 to 0.9 would need to be selected. Unfortunately, 

this means that species in the moderate 

and low categories will receive more water than 

needed, which may result in injury. 

Assigning Species Factors to Plantings 

1. For single-species plantings— 

When only one species occurs 

Considering that plantings with mixed water 

needs are not water-efficient in most cases and 

in the irrigation zone, use the ks 

value assigned in the WUCOLS 

list. For example, coyote brush 

is assigned to the “low” category 

and has a ks value from 

0.1 to 0.3. 

2. For multiple-species plantings— 

a. When species have similar 

water needs: In well-planned 

hydrozones where species of 

similar water requirements are 

used, the selection of a ks value 

is straightforward: simply select 

the category to which all 

Plant injury may occur when species with different water needs are planted in a single 

irrigation zone. During a drought, irrrigation was withdrawn from this planting of star 

jasmine (Trachelospermum jasminioides) and cotoneaster (Cotoneaster sp). Subsequently, 

star jasmine was severely injured, while cotoneaster was not visibly affected. 

14

the incidence of plant injury may 

increase, some management options 

are worth considering: 

• If only a small number or percentage 

of plants are in the high 

category, then the replacement 

of such plants with species with 

lower water needs would allow 

for the selection of a ks in a 

lower range. 

• If all plants are to be retained, 

but a level of appearance somewhat 

less than optimal is acceptable, 

then a ks value from 

a lower range may be selected. For example, 

in the case where plants in the low, moderate, 

and high categories are in the same irrigation 

zone, a ks value from the moderate range may 

be selected with the understanding that some 

injury to species in the high category may result. 

• In cases where all plants are to be retained and 

no water stress injury is acceptable, then 

supplemental irrigation for species in the high 

category should be considered. Again using 

the case where species in low, moderate, and 

high categories are planted in the same irrigation 

zone, a ks value from the moderate range 

may be selected for the planting, provided additional 

water is supplied to individual plants 

with higher water needs. This approach requires 

an adjustment to the irrigation system 

whereby additional sprinklers or emitters are 

used to deliver supplemental water to species 

with higher water requirements. 

Certain species, such as these coast live oak (Quercus agrifolia), can maintain health and 

appearance without irrigation (after they become established). Such species are grouped 

in the “very low” category and are assigned a species factor of less than 0.1. Many 

California native species are in this category. 

3. For species in the “very low” category— 

It is important to remember that certain species 

can maintain health and appearance without irrigation 

after they become established. Such 

species are grouped in the “very low” category 

and are assigned a ks of less than 0.1. Essentially 

this classification means that species in this 

group do not need to be irrigated unless winter 

rainfall is abnormally low. Accordingly, if no 

irrigation is supplied, then there is no need to 

calculate a landscape coefficient and a ks value 

is not assigned. In low rainfall years, some irrigation 

may be needed, however, and a ks value 

of 0.1 should be sufficient to maintain health 

and appearance in these species. 

Density Factor (kd) 

The density factor is used in the landscape coefficient 

formula to account for differences in vegetation 

density among landscape plantings. Vegetation 

density is used here to refer to the collective 

leaf area of all plants in the landscape. Differences 

15

in vegetation density, or leaf area, lead to differences 

in water loss. 

and distribution is not uniform and where a mixture 

of vegetation types exist. 

The density factor ranges in value from 0.5 to 1.3. 

This range is separated into three categories: 

Low 0.5 - 0.9 

Average 1.0 

High 1.1 - 1.3 

Immature and sparsely planted landscapes typically 

have less leaf area than mature or densely planted 

landscapes, and thus lose less water. These plantings 

are assigned a kd value in the low category. Plantings 

with mixtures of vegetation types (trees, shrubs, and 

groundcovers) typically have greater collective leaf 

areas than plantings with a single vegetation type, 

and thus will lose more water. These plantings are 

assigned a density factor value in the high category. 

Plantings which are full but are predominantly of 

one vegetation type, are assigned to the average category. 

Example: The grounds manager of a college campus 

in San Diego wants to determine the landscape 

coefficient for a planting consisting of gazania 

groundcover and a few widely-spaced escallonia 

shrubs. Since the plants cover the ground surface 

completely, the planting is considered to be full. 

Based on these vegetation density characteristics 

(i.e., full and predominantly of one vegetation type), 

the manager determines that this is an average density 

planting and assigns a kd value of 1.0. 

Although this example might infer that the selection 

of the density factor is fairly simple, it can be 

difficult to determine. Vegetation density varies 

considerably and assigning density factors can be 

confusing. Many cases exist where plant spacing 

Unfortunately, a standardized system of evaluating 

vegetation density for landscapes does not exist. 

Nonetheless, limited information from agricultural 

systems (principally orchards) can be applied to 

landscapes. The following sections describe two 

terms, canopy cover and vegetation tiers, which 

when applied to landscape plantings provide some 

guidance in assessing vegetation density. 

Canopy Cover 

Canopy cover is defined as the percentage of ground 

surface within a planting which is shaded by the 

plant canopy (or, simply, percent ground shading). 

A planting with full canopy cover will shade 100% 

of the ground surface, while a 50% canopy cover 

will cast a shadow on 50% of the ground area. The 

higher the canopy cover the greater the density of 

vegetation on a surface area basis. 

Most mature landscape plantings have a complete 

canopy cover, i.e., the trees, shrubs, and groundcovers 

shade 100% of the ground surface. New 

plantings, immature plantings, and widely-spaced 

plantings are examples of cases where the canopy 

cover is less than 100%. 

Orchard data gives an indication of how canopy 

cover affects water loss. Studies show that water 

loss from orchards does not increase as canopy cover 

increases from 70% to 100%. Below 70% cover, 

however, orchard water loss declines. 

Applying this information to landscapes, plantings 

of trees with a canopy cover of 70% to 100% constitutes 

a complete canopy cover condition, and 

16

would be considered as average for density factor 

assessments. A tree planting with less than 70% 

canopy cover would be in the low category. 

For plantings of shrubs and groundcovers, a canopy 

cover of 90% to 100% constitutes complete cover. 

This represents an average condition for density factor 

assessments, while less than 90% cover would 

be in the low category. 

Vegetation Tiers 

Canopy cover gives an assessment of vegetation 

density on an area basis, i.e., the percent ground area 

covered by vegetation describes 

the closeness or sparseness 

of plants in a planting. 

Another dimension needs to be 

considered for landscapes: the 

vertical dimension. Landscapes 

are frequently composed 

of plants of various 

heights: tall trees, low groundcovers, 

and shrubs somewhere 

in between. Due to the typical 

growth form of each vegetation 

type, “tiers” of vegetation result. 

When combinations of these 

vegetation types occur in a 

planting they add a height element 

which will have an affect on water loss. In 

orchard plantings, for example, field research has 

shown that the addition of a cover crop increases 

evapotranspiration from 25% to 80% above a bare 

soil condition. In other words, adding a 

groundcover-like planting beneath orchard trees results 

in a substantial increase in water loss. 

In landscapes, groundcovers and/or shrubs planted 

in the understory of trees are likely to have a similar 

effect on water loss as found in orchard settings. 

Additionally, by adding trees to a groundcover planting 

or shrubs to a tree-groundcover planting, an increase 

in water loss would be expected. 

In most cases, the presence of vegetation tiers in 

landscapes constitutes a high density condition. For 

example, a planting with two or three tiers and complete 

canopy cover would be considered to be in the 

high kd category . 

Landscapes are frequently composed of plants of various heights: trees, groundcovers, and 

shrubs. Due to the typical growth form of each vegetation type, “tiers” of vegetation result. 

Plantings with more than one tier are likely to lose more water than a planting with a single tier. 

Here, the trees and shrubs in the groundcover represent a higher water loss condition than if the 

groundcover occurred alone. The density factor accounts for differences in vegetation density. 

Plantings with multiple tiers which do not have a 

complete canopy cover, however, may not constitute 

a high density condition. A new planting with 

trees, shrubs, and groundcovers, for example, has 

three vegetation tiers but canopy density is low. Although 

three tiers are present, this planting would 

be classified as low density. 

17

Assigning Density Factor Values 

Canopy cover and vegetation tiers are used to assess 

vegetation density for density factor assignments. 

Since it is very difficult to account for all 

the variation in vegetation density which occurs 

in landscapes, the following assignments are 

made simply as a guide to making reasonable assessments. 

Average Density: kd = 1.0 

Plantings of one vegetation type: for trees, 

canopy cover of 70% to 100% constitutes an average 

condition. For shrubs or groundcovers, a 

canopy cover of 90% to 100% is considered to be 

an average condition. 

This mixed planting of Wheeler’s pittosporum (Pittosporum tobira 

‘Wheeler’s Dwarf’), Indian hawthorne (Rhaphiolepis indica), American 

sweetgum (Liquidambar styraciflua), and coast redwood (Sequoia 

sempervirens) is considered to be average density (kd = 1.0). Trees are 

widely spaced through the sub-shrub/groundcover planting area. 

Plantings of more than one vegetation type: for 

mixed vegetation types, an average density condition 

occurs when one vegetation type is predominant 

while another type occurs occasionally in the 

planting, and canopy cover for the predominant vegetation 

type is within the average density specifications 

outlined above. For example, a mature 

groundcover planting (greater than 90% canopy 

cover) which contains trees and/or shrubs that are 

widely spaced would be considered to be average 

density. Additionally, a grove of trees (greater than 

70% canopy cover) which contains shrubs and/or 

groundcover plants which are widely spaced would 

constitute an average condition. 

Plantings of a single species, such as this iceplant groundcover 

(Drosanthemum sp), are considered to have average density (kd = 

1.0) when full (90 - 100% cover). 

Low Density: kd = 0.5 - 0.9 

Low density plantings are characterized largely by 

canopy covers less than those specified for the average 

density condition. For instance, a tree planting 

with less than 70% canopy cover would be assigned 

a kd value less than 1.0. The precise value 

assigned (between 0.5 and 0.9) would be based on 

the canopy cover assessment: a lower kd value for 

a thinner canopy cover. 

18

For shrubs and groundcovers, canopy cover less than 

90% constitutes a density less than average and a kd 

value less than 1.0 would be assigned. 

Plantings with mixed vegetation types generally 

have greater canopy covers than those of a single 

type. For instance, a groundcover planting with 

canopy cover of 50% constitutes a low density condition 

and a kd of 0.7 might be assigned. If an occasional 

tree occurs in the planting, then the principal 

effect is one of increasing canopy cover, and an 

upward adjustment in kd to 0.8 or 0.9 would be warranted. 

High Density: kd = 1.1 - 1.3 

When canopy cover is full for any vegetation type, 

then increases in density result from increases in 

the number of plants of other vegetation types. For 

example, by adding trees to a mature groundcover 

planting (groundcover canopy cover = 100%), an 

increase in vegetation density occurs. The addition 

of shrubs to the planting further increases the density. 

This mix of vegetation types creates a layering 

or tiering of vegetation which represents potential 

increases in water loss. Upward adjustments of kd 

can be made to account for vegetation tiering. The 

highest density condition, where all three vegetation 

types occur in substantial numbers in a 

planting, would be assigned a kd of 1.3. In 

plantings where lesser degrees of vegetation tier- 

Microclimate Factor (kmc) 

Microclimates exist in every landscape and need to 

be considered in estimates of plant water loss. Features 

typical of urban landscapes (such as buildings 

and paving) influence temperature, wind speed, light 

intensity and humidity. These features vary considerably 

among landscapes, resulting in differences 

in microclimate. To account for these differences, 

a microclimate factor (kmc) is used. 

The microclimate factor ranges from 0.5 to 1.4, and 

is divided into three categories: 

Low 0.5 - 0.9 

Average 1.0 

High 1.1 - 1.4 

The microclimate factor is relatively easy to set. An 

“average” microclimate condition is equivalent to 

reference evapotranspiration conditions, i.e.., an 

open-field setting without extraordinary winds or 

heat inputs atypical for the location. This microclimate 

is not substantially affected by nearby buildings, 

structures, pavements, slopes, or reflective surfaces. 

For example, plantings in a well-vegetated 

park which are not exposed to winds atypical of the 

area, would be assigned to the average microclimate 

category. 

ing occurs (e.g., a two-tiered planting), then a kd 

value of 1.1 or 1.2 is appropriate. 

For shrubs and groundcovers, canopy cover less than 90% constitutes a 

density less than average (kd < 1.0). This mixed planting would be 

assigned a low density value (0.5 - 0.9). 

19

Plantings in a well-vegetated park, which are not exposed to winds atypical for the area, would be 

assigned to the average microclimate category (kmc = 1.0). These conditions are similar to those used 

for reference evapotranspiration measurements (CIMIS stations). 

“Low” microclimate conditions 

are as common as high 

microclimate conditions. 

Plantings that are shaded 

for a substantial part of the 

day or are protected from 

winds typical to the area 

would be assigned low values. 

These include the 

north side of buildings, 

courtyards, under building 

overhangs, and on the north 

side of slopes. 

In a “high” microclimate condition, site features increase 

evaporative conditions. Plantings surrounded 

by heat-absorbing surfaces, reflective surfaces, or 

exposed to particularly windy conditions would be 

assigned high values. For example, plantings in 

street medians, parking lots, next to southwest-facing 

walls of a building, or in “wind tunnel” areas 

would be assigned to the high category. 

The high and low microclimate categories have 

ranges of values. For example, the low category 

ranges from 0.5 to 0.9. The specific value assigned 

within a category will depend on an assessment of 

the degree to which the microclimate will affect plant 

water loss. For example, trees in a parking lot which 

are exposed to constant winds (atypical for the general 

area) will be assigned a higher value in the high 

category than if the location 

was not windy. Conversely, 

a courtyard planting 

in afternoon shade and 

protected from winds will 

be assigned a kmc value in 

the low category, but less 

than that for a planting 

without afternoon shading. 

Plantings surrounded by heat-absorbing surfaces, reflective surfaces, or exposed to particularly windy 

conditions would be assigned a high microclimate value (1.1 - 1.4). 

Example: An irrigation 

consultant is estimating 

landscape water requirements 

for a large residential 

development. The 

buildings, parking lots, 

20

walkways, and open areas at 

the site create substantially 

different microclimates 

within plantings. Starting 

with the open areas, he determines 

that conditions are 

quite similar to reference ET 

measurement sites and assigns 

them to the average category 

(kmc = 1.0). Trees in 

the parking lot are exposed 

to heat from the asphalt pavement 

and reflected light 

from cars and are assigned 

to the high category. Since 

the parking lot is not exposed 

to extraordinary winds, however, he chooses 

a midrange value of 1.2. Shrub and groundcover 

plantings on the northeast side of buildings are 

shaded for most of the day and are assigned to the 

low category. Being protected from winds typical 

of the area as well, they are given a kmc value of 0.6, 

in the lower end of the range. 

Plantings that are shaded for a substantial part of the day, or are protected from winds typical to the 

area, are assigned low microclimate values (0.5 - 0.9). This planting on the northeast side of the 

office building is shaded for several hours each day. 

Assigning Microclimate Factor Values 

Average Microclimate: kmc = 1.0 

Site conditions equivalent to those used for reference 

ET measurements represent an average microclimate. 

Reference ET is measured in an open-field 

setting which is not exposed to extraordinary winds 

or heat inputs from nearby buildings, structures, or 

vehicles. Plantings in similar conditions would be 

considered to be in an average microclimate. 

Plantings in park settings are most typically assigned 

to this category. Although some hardscape may 

exist, vegetation dominates the landscape. Large 

plantings of groundcover, groves of trees, and mixtures 

of shrubs, turf, and trees in relatively open areas 

represent examples of an average microclimate 

condition. Small parks with adjacent buildings, extensive 

hardscapes, or exposed to extraordinary 

winds would not be included in the average category. 

Low Microclimate: kmc = 0.5 - 0.9 

Sites which are shaded or protected from winds typical 

to the area are considered to be in the low microclimate 

category (Costello et al. 1996). Features 

of the site modify the microclimate such that evaporative 

conditions are less than those found in the 

average microclimate. Plantings located on the north 

side or northeast side of buildings, shaded by overhead 

structures, or within courtyard settings are typically 

assigned a kmc value in the low range. Plantings 

protected from winds by buildings, structures, or 

other vegetation also would be assigned to the low 

category. The specific value assigned for the microclimate 

factor will depend on the specific site 

conditions. For example, a planting in a courtyard 

which is shaded most of the day and protected from 

winds may be assigned a value of 0.6, while a simi- 

21

lar planting which is located on the northeast side 

of a building may be assigned a value of 0.8. 

High Microclimate: kmc = 1.1 - 1.4 

Sites which are exposed to direct winds atypical for 

the area, heat inputs from nearby sources, and/or 

reflected light would be considered to be in the high 

microclimate category. These features of the site 

increase evaporative conditions above those found 

in an average microclimate condition. Plantings located 

in medians, parking lots, or adjacent to south 

or southwest facing walls which are exposed to 

higher canopy temperatures than those found in a 

well-vegetated setting would be in the high category. 

Plantings in wind tunnel locations and those receiving 

reflected light from nearby windows, cars, or 

other reflective surfaces are also in high microclimate 

conditions. The specific value assigned will 

depend on the specific conditions. For example, a 

shrub planting located next to a southwest facing 

wall may be assigned a kmc value of 1.2, while a 

similar planting next to a southwest wall which is 

composed of reflective glass and is exposed to extraordinary 

winds may be assigned a value of 1.4. 

Table 3— 

Summary Table 

Values for Landscape Coefficient Factors 

High Moderate Low Very Low 

Species Factor* (ks) 0.7-0.9 0.4-0.6 0.1-0.3

Chapter 3— 

Using the Landscape 

Coefficient Formula 

The landscape coefficient formula was introduced 

in Chapter 2, and the three factors which determine 

its value were discussed. Now these factors are used 

to calculate values for the landscape coefficient. A 

series of field cases show the range of values that 

can be determined for KL. In Chapter 4, calculations 

using the landscape coefficient in the ETL formula 

are presented. 

Using the information presented in Chapter 2, values 

for the landscape coefficient can be calculated. 

The following cases show how the landscape coefficient 

is used for a variety of species, density, and 

microclimate conditions. Species factor values will 

be taken from the WUCOLS list, while density and 

microclimate values are based on the planting and 

site conditions described. For quick reference, the 

following table gives values for each factor. 

Landscape Coefficient Factors 

Species Density Microclimate 

High 0.7 - 0.9 1.1 - 1.3 1.1 - 1.4 

Mod./Ave. 0.4 - 0.6 1.0 1.0 

Low 0.1 - 0.3 0.5 - 0.9 0.5 - 0.9 

Very Low < 0.1 

Case 1—A large, mature planting of star jasmine in 

a park in San Jose. It is in full sun and has little 

wind exposure. 

ks = 0.5 

kd = 1.0 

kmc = 1.0 

KL = 0.5 x 1.0 x 1.0 = 0.5 

Analysis: Star jasmine is classified as moderate in 

the WUCOLS list (moderate range = 0.4 to 0.6) and 

a midrange ks value of 0.5 is assigned. Since the 

planting is mature it will be considered full (i.e., 

canopy cover = 100%), and being of one vegetation 

type, it is classified as an average density and kd is 

1.0. The microclimate is similar to reference evapotranspiration 

conditions (full sun, open area, no extraordinary 

winds) and, therefore, is classified as 

average and kmc is 1.0. 

Case 2—A mixed planting of dwarf coyote brush, 

Pfitzer juniper, oleander, purple hopseed, and olive 

in an office park in Los Angeles. The planting is 

full, exposed to sun all day, but not to extraordinary 

winds. 

ks = 0.2 

kd = 1.2 

kmc = 1.0 

KL = 0.2 x 1.2 x 1.0 = 0.24 

Analysis: All species are classified as low in the 

WUCOLS list and are assigned a midrange value 

of 0.2. Canopy cover is 100%, and since all three 

vegetation types occur, this is classified as a high 

density planting and a kd value of 1.2 is assigned. 

The microclimate is average and a value of 1.0 is 

assigned. 

Case 3—A mature planting of rockrose, star jasmine, 

and dichondra in an amusement park in Sacramento. 

The planting is in full sun and atypical winds are 

infrequent. 

ks = 0.8 

kd = 1.0 

kmc = 1.0 

KL = 0.8 x 1.0 x 1.0 = 0.8 

Analysis: Species in this planting are in three different 

WUCOLS categories: low (rockrose), mod- 

23

erate (star jasmine), and high (dichondra). To maintain 

the dichondra in good condition, a ks value of 

0.8 is needed. This means, however, that both the 

rockrose and star jasmine will receive more water 

than they need. Obviously this is not a water-efficient 

planting. Both the density and microclimate 

conditions are average and were assigned values of 

1.0. 

Case 4—A widely-spaced planting of camellia on a 

university campus in San Francisco. Canopy cover 

of the planting is 40% to 50%. A 4-inch mulch covers 

the ground throughout the planting. It is in full 

sun and no extraordinary winds occur. 

ks = 0.5 

kd = 0.5 

kmc = 1.0 

KL = 0.5 x 0.5 x 1.0 = 0.25 

Analysis: Camellia is classified as moderate in the 

WUCOLS list and is assigned a midrange value of 

0.5. This is a low density planting of a single species 

and a kd value of 0.5 is assigned. The microclimate 

is average and given a value of 1.0. 

Case 5—A planting of leatherleaf mahonia and 

Burford holly in an office park in Pasadena. The 

planting is full, but shaded in the afternoon by an 

adjacent building. The building also blocks afternoon 

winds typical for the area. 

ks = 0.5 

kd = 1.0 

kmc = 0.6 

KL = 0.5 x 1.0 x 0.6 = 0.30 

Analysis: Both species are classified as moderate 

in the WUCOLS list and are assigned a midrange 

value of 0.5. The canopy cover is full and since 

only one vegetation type occurs, it is classified as 

average density. Since the building shades the planting 

and protects it from wind, the microclimate is 

low and a kmc value of 0.6 is assigned. 

Case 6—A mixed planting of sweetgum, Rhaphiolepis 

sp., Wheeler's dwarf pittosporum, Raywood ash, and 

English ivy at a zoo in San Diego. The planting is 

mature (canopy cover is 100%), in full sun, and exposed 

to continual strong winds not typical for the 

area (i.e., windier than the reference ET location). 

ks = 0.5 

kd = 1.2 

kmc = 1.3 

KL = 0.5 x 1.2 x 1.3 = 0.78 

Analysis: All species in this planting are classified 

as moderate in the WUCOLS list and are assigned a 

midrange value of 0.5. Since the canopy cover is 

100% and all three vegetation types occur, this is a 

high density planting and a kd of 1.2 is assigned. 

Since the site is atypically windy for the area, the 

microclimate is classified as high and a kmc of 1.3 is 

assigned. 

Case 7—A new planting of rockrose, manzanita, 

pink melaleuca, and bushy yate along a freeway in 

Monterey County. All plants are 5-gallon container 

stock, planted in full sun, and are not exposed to 

extraordinary winds. Canopy cover is 20 to 30%. 

A 4-inch layer of mulch covers the ground throughout 

the planting. 

ks = 0.2 

kd = 0.5 

kmc = 1.0 

KL = 0.2 x 0.5 x 1.0 = 0.1 

Analysis: All species in this planting are classified 

as low in the WUCOLS list and a midrange value 

of 0.2 is given. Since this is a new planting and 

canopy cover is not full, it is placed in a low density 

category and assigned a kd value of 0.5. The micro- 

24

climate is average and assigned a value of 1.0. (See 

Chapter 8 for information on irrigating new 

plantings.) 

These field examples should provide an understanding 

of how values for each of the landscape coefficient 

factors are assigned and used. In addition, an 

appreciation for the diversity of species, differences 

in vegetation density, and variation in microclimates 

which exist in landscapes should be realized. In 

many cases, there will be a different landscape coefficient 

for each irrigation zone. 

For discussions of the following special planting 

cases, refer to Chapter 8: 

• New Plantings 

• Trees in Turf 

• Individual Specimens 

• Vines 

• Herbaceous Plants 

Landscapes vary considerably 

in species composition, 

vegetation density and 

microclimates. 

25

Chapter 4— 

Using the Landscape 

Coefficient to Estimate 

Landscape 

Evapotranspiration 

The landscape coefficient and reference evapotranspiration 

now are used to estimate landscape evapotranspiration 

for the plantings described in 

Chapter 3. This chapter completes the process used 

to produce estimates of landscape water loss. Subsequent 

chapters discuss how to use estimates of 

ETL to calculate total irrigation water needs and how 

to apply this information in landscape management 

programs. 

In Chapter 3, seven landscape planting cases were 

described and used for landscape coefficient calculations. 

These cases will be used here to calculate 

landscape evapotranspiration with the ETL formula. 

The ETL formula was described in Chapter 2 and is 

presented here for quick reference: 


Landscape Evapotranspiration = 

Landscape Coefficient x Reference Evapotranspiration 

For each case, reference evapotranspiration (ETo) 

values will be taken from Appendix A. All are normal 

year average values for the month of July for 

the respective locations. 

Case 1— KL = 0.5 

ETo for San Jose = 7.44 inches 

ETL = 0.5 x 7.44 = 3.72 inches 

Case 2— KL = 0.24 

ETo for Los Angeles = 6.5 inches 

ETL = 0.24 x 6.5 = 1.56 inches 

Case 3— KL = 0.8 

ETo for Sacramento = 8.6 inches 

ETL = 0.8 x 8.6 = 6.88 inches 

Case 4— KL = 0.25 

ETo for San Francisco = 4.9 inches 

ETL = 0.25 x 4.9 = 1.22 inches 

Case 5— KL = 0.30 

ETo for Pasadena = 7.4 inches 

ETL = 0.30 x 7.4 = 2.22 inches 

Case 6— KL = 0.78 

ETo for San Diego = 5.8 inches 

ETL = 0.78 x 5.8 = 4.59 inches 

Case 7— KL = 0.1 

ETo for Monterey = 5.5 inches 

ETL = 0.1 x 5.5 = 0.55 inches 

These calculations show that landscape irrigation 

water needs vary substantially. Estimates range from 

0.55 inches to 6.88 inches—more than a 12-fold difference. 

The two factors used to determine ETL, the landscape 

coefficient and reference evapotranspiration, 

are solely responsible for producing these differences 

in water loss estimates. For plantings in the 

same location (i.e., where the same ETo values will 

be used), the differences will arise solely from the 

landscape coefficient. To produce useful estimates 

of water loss, therefore, it is important to carefully 

determine the value of KL. 

27

Even though the ETL formula has given an estimate 

of water loss from a landscape, the total amount of 

irrigation water needed has not been determined. 

The total amount is calculated from two factors: ETL 

and irrigation efficiency. The following chapter discusses 

irrigation efficiency and shows how it is used 

to determine the total amount of water to apply. 

28

Chapter 5— 

Irrigation Efficiency 

and Calculating the 

Total Amount of Water 

to Apply 

The first four chapters have described the process 

for estimating plant water needs. To calculate the 

total amount of water to apply, irrigation efficiency 

needs to be addressed. This chapter introduces the 

formula for calculating total water needs and discusses 

the irrigation efficiency factor. How this 

information applies to irrigation management is discussed 

in Chapter 6. 

The ETL formula calculates the amount of irrigation 

water needed to meet the needs of plants. This 

is not the total amount of water needed to apply, 

however. Since every irrigation system is inefficient 

to some degree, the landscape will require 

water in excess of that estimated by ETL. In this 

chapter, irrigation efficiency will be discussed and 

then used to calculate the total amount of water to 

apply. 


Efficiency can be defined as the beneficial use of 

applied water (by plants). The following formula 

is used to calculate irrigation efficiency: 

Irrigation Efficiency (%) = Beneficially Used Water x 100 

Total Water Applied 

An efficiency of 100% would mean that all applied 

water was used by the planting. This rarely occurs. 

Consequently, irrigation efficiency is less than 100% 

Not all water applied to landscapes is used by plants. Some is lost 

due to runoff, windspray, or deep percolation. Irrigation efficiency 

losses need to be included in water budget calculations. 

in virtually all cases and additional water should be 

applied to account for efficiency losses. 

A determination of irrigation efficiency (IE) for 

landscape plantings is challenging. As yet, a standard 

method has not been established. The approach 

used for turf irrigation, distribution uniformity (DU), 

is not appropriate for most landscape plantings. 

Three approaches are considered here: calculation, 

estimation, and goal setting. Each method has significant 

limitations, and are presented here only as 

possible options to consider. 

29

Calculation 

To calculate irrigation efficiency, values for ETL and 

TWA are needed. In landscapes, beneficially used 

water is the equivalent of ETL (the amount of water 

estimated to be needed by a planting). This is calculated 

as described in Chapter 4. The total water 

applied can be determined by operating an irrigation 

system for a scheduled cycle and measuring 

the total water used (usually read from a water 

meter). The following example shows a typical 

calculation: 

ETL = 4 inches (calculated using the ETL formula) 

TWA = 5 inches (measured) 

IE = ETL x 100 = 80% 

TWA 

In the above example, the system has an 80% efficiency, 

or 8 out of every 10 gallons of applied water 

is used beneficially by the planting. Two gallons 

are lost, perhaps to runoff, evaporation, leakage, or 

wind spray. To supply 8 gallons of water means 

that a total of 10 gallons needs to be applied. 

This approach has limited application for two reasons: 

1. it requires a water meter to measure the amount 

of water applied, and 

2. it may include efficiency losses associated with 

poor scheduling. 

It assumes that applied water is close to optimum 

for the landscape plants and the system operating 

capabilities. It may be, however, that inefficiencies 

are linked to the operating schedule. For example, 

the irrigation duration may be too long for the planting. 

Estimation 

In cases where the total water applied cannot be 

measured, then irrigation efficiency may be estimated. 

Estimates are based on an assessment of the 

design and performance of the irrigation system. A 

system which is well designed and operated can have 

an efficiency range of 80% to 90%. Poorly designed 

and operated systems may have efficiencies of less 

than 50%. A representative range of efficiencies 

for landscape systems is proposed here to be from 

65% to 90%. 

Estimating is a subjective process where two assessments 

of the same system can vary widely. The 

utility of an estimate will be related to the knowledge 

and experience of the estimator. 

Goal Setting 

Irrigation efficiency values may also be based on a 

design and/or management goal. For instance, a new 

landscape may be designed to achieve an irrigation 

efficiency of 90%. Or, an existing landscape may 

be managed to achieve an irrigation efficiency of 

85%. Both values represent efficiency goals. These 

efficiency values are then used to estimate the total 

water needed to achieve the goal. This approach is 

useful for water budgeting purposes, but does not 

provide a useful estimate of actual system performance. 

All three of these methods are highly approximate. 

Until a standard method of measuring landscape irrigation 

efficiency is determined, however, they provide 

some guidance. 

30

Total Water Applied 

Regardless of the method used to determine irrigation 

efficiency, the total amount of water needed for 

a landscape planting is calculated using the following 

formula: 

TWA = ETL 

IE 

Total Water Applied = Landscape Evapotranspiration 


The following are examples of calculations using 

irrigation efficiency and landscape evapotranspiration 

to determine the total water to apply. The first 

three cases presented in Chapters 3 and 4 will be 

used. An irrigation efficiency value of 70% is assigned 

for each case. 

Case 1— 

ETL = 3.72 inches 

IE = 70% or 0.7 

The magnitude of this effect can be seen in the following 

calculations where IE values from 30% to 

90% are used. The ETL value from the first sample 

calculation (3.72 inches) is used in each case. 

@ 30% IE, TWA = 3.72 = 12.4 inches 

0.3 

@ 60% IE, TWA = 3.72 = 6.2 inches 

0.6 

@ 90% IE, TWA = 3.72 = 4.1 inches 

0.9 

These calculations indicate that for the same landscape 

plants, at the same location, and under identical 

environmental conditions, the total amount of 

water applied varies from 4.1 inches to 12.4 inches, 

due solely to irrigation efficiency differences. 

Clearly, the IE factor needs to be addressed very 

carefully when planning and managing landscapes. 

TWA = 3.72 = 5.31 inches 

0.7 

(see Case 1 in Chapter 4) 

Case 2— 


IE = 70% or 0.7 

TWA = 1.56 = 2.22 inches 

0.7 

Case 3— 


IE = 70% or 0.7 

TWA = 6.88 = 9.8 inches 

0.7 

It is clear from these calculations that irrigation efficiency 

plays a very large role in determining the 

total amount of water to apply. Water added to account 

for efficiency losses ranges from 0.67 inches 

to 2.88 inches. 

If the efficiency of the system is greater or less than 

70%, the total water applied will vary accordingly. 

31

Chapter 6— 

Putting It All 

Together: A Worksheet 

for Calculations 

Chapters 1 through 5 have introduced a number of 

formulas and numbers that are used to estimate landscape 

water needs. This chapter puts all the equations 

together to show the calculation process. Subsequent 

chapters discuss considerations for applying 

estimates and special planting situations. 

Three steps are needed to estimate irrigation water 

needs of a planting: 

1. calculate the landscape coefficient, 

Converting Inches to Gallons 

Landscape evapotranspiration (ETL) and total 

water applied (TWA) values have been given in 

units of inches. Frequently, it is of interest to know 

how many gallons of water are needed. Inches of 

water can be converted to gallons by using: 1) a 

conversion factor, and 2) a measure of the area to 

be irrigated. 

1) The conversion factor, 0.62, can be used to 

convert inches-of-water-per-square-foot to gallons. 

A volume that is one-foot long, one-foot 

wide, and one-inch deep contains 0.62 gallons 

of water. This means that there are 0.62 gallons 

of water in a square-foot-inch. (There are 

325,851 gallons in an acre-foot of water.) 

2. calculate landscape evapotranspiration, and 

3. calculate the total water applied. 

These steps are combined in a worksheet format on 

the following page. After the worksheet, an example 

is given to show how it is used, followed by a discussion 

of converting units from inches of water to 

gallons. 

2) The area to be irrigated needs to be measured. 

To use the conversion factor, units of squarefeet 

are required. 

With the area and the conversion factor, gallons 

of water can be calculated using the following formula: 

Estimated water in gallons = estimated water in 

inches x area (square feet) x 0.62 

Example: It was determined that 2.11 inches of 

water was needed for a groundcover planting. 

Let’s say the planting covers 5,000 square feet. 

To convert inches to gallons: 

Gallons = 2.11 inches x 5,000 sq. ft. x 0.62 = 6,541 

It is estimated that 6,541 gallons of water are 

needed to maintain the 5,000 square feet of 

groundcover. 

33

Worksheet for Estimating Landscape Water Needs 

Step 1: Calculate the Landscape Coefficient (KL) 

KL formula: KL = ks x kd x kmc ........................ 

ks = species factor 

kd = density factor 

kmc = microclimate factor 

ks = ______ (range = 0.1-0.9) (see WUCOLS list for values) 

kd = ______ (range = 0.5-1.3) (see Chapter 2) 

kmc = _____ (range = 0.5-1.4) (see Chapter 2) 

KL = _____ x _____ x _____ = _____ . 

(ks) (kd) (kmc) 

Step 2. Calculate Landscape Evapotranspiration (ETL) 

ETL formula: ETL = KL x ETo ........................... 

KL = landscape coefficient 

ETo = reference evapotranspiration 

KL = ______ (calculated in Step 1) 

ETo = _____ inches (listed in Appendix A for month and location) 

ETL = _____ x _____ = _____ inches. 

(KL) (ETo) 

Step 3. Calculate the Total Water to Apply (TWA) 

TWA formula: TWA = ETL ................................. ETL = landscape evapotranspiration 

IE .................................. IE = irrigation efficiency 

ETL = ______ (calculated in Step 2) 

IE = _______ (measured, estimated, or set) (see Chapter 5) 

TWA = ETL 

IE 

= ______ inches 

34

Worksheet Example 

A landscape manager in San Bernardino is interested 

in estimating water requirements for a large 

planting of African daisy (Osteospermum 

fruticosum) for the month of July. The planting is 

in an open area and is not exposed to extraordinary 

winds for the area. The manager estimates that irrigation 

efficiency is 70% and, using the work-sheet, 

follows the three steps (see below). 

Step 1. 


ks = 0.2 (from WUCOLS list) 

kd = 1.0 (complete canopy cover and one vegetation type) 

kmc = 1.0 (open area, no extraordinary winds) 

KL = 0.2 x 1.0 x 1.0 = 0.2 

Step 2. 


KL = 0.2 (from Step 1) 

ETo = 7.4 inches (for July in San Bernardino) (see Appendix A) 

ETL = 0.2 x 7.4 = 1.48 inches 

Step 3. 

TWA = ETL 

IE 

ETL = 1.48 inches (from Step 2) 

IE = 0.7 (70% irrigation efficiency estimated by landscape manager) 

TWA = 1.48 inches = 2.11 inches 

0.7 

(To convert 2.11 inches of water to gallons, see "Inches to Gallons".) 

The landscape manager has estimated that the 

groundcover will need 2.11 inches of water for the 

month of July. Using this estimate, the manager 

can develop an irrigation schedule. Other factors 

may need to be considered before deciding if this 

estimate is appropriate for the planting. Chapter 7 

addresses these considerations. 

35

Chapter 7— 

Using Water Estimates 

in Landscape Planning 

and Management 

Before water needs estimates are used for landscape 

planning and management purposes, a few points 

need to be considered. In Chapter 7, five special 

topics which are relevant to using estimates are addressed. 

The following chapter discusses some special 

planting situations. 

The previous chapters have described how to estimate 

irrigation water needs for landscape plantings. 

These estimates can be used in landscape planning 

and management to: 

• develop water budgets for planned or existing 

landscapes, 

• assist in the design of landscapes to meet irrigation 

goals, 

• assist in designing and managing effective 

hydrozones, 

• help in the determination of irrigation system efficiency 

(i.e., along with measurements of total 

water use), and 

• serve as an auditing tool by providing assessments 

of the amount of water landscapes need compared 

to that actually being used. 

When using landscape water estimates for these 

purposes, however, a few considerations are important 

to note. These are discussed briefly under the 

following special topics headings. 

Field Adjustments 

The landscape coefficient method provides estimates 

of water needs, not exact values. Consequently, 

adjustments likely are needed in the field. 

If plants are showing signs of water stress, then an 

upward adjustment will be needed. Conversely, 

when it appears that too much water is being applied, 

then a downward adjustment is warranted. It 

is strongly recommended that when irrigation water 

estimates are implemented in the field that they 

be followed by careful monitoring. 

Irrigation Schedules 

An estimate of water needs is the first step in developing 

an irrigation schedule. Irrigation frequency, 

duration, and cycles also need to be determined to 

create a schedule. These are determined from the 

soil infiltration rate, rooting depth, sprinkler application 

rate, allowable depletion amounts, and soil 

water holding capacity. Each of these factors needs 

to be evaluated to determine how frequently to irrigate, 

how long to irrigate at any one time, and how 

many irrigation cycles are needed. 

Soil Evaporation 

Water loss may occur from the soil as well as from 

plants. This is most common when ground shading 

is less than 100% and a mulch is not present. The 

rate of evaporative water loss from soils depends 

on soil wetness, texture, structure, and density. 

When soil evaporation contributes to landscape 

water losses, water estimates should be increased 

by 10% to 20%. With sufficient mulching, however, 

bare soil surfaces will not be a source of water 

loss. 

37

Salts and Leaching Fractions 

When soil salt concentrations are sufficiently high 

to cause plant injury, the application of water in 

excess of that needed to meet plant needs is necessary. 

This process is called “leaching” and the percentage 

of applied water used to move salts below 

the root zone is called the “leaching fraction”. For 

example, if 100 gallons of water is applied, and 

25 gallons percolated below the root zone to remove 

salts, this would be a 25% leaching fraction. The 

leaching fraction needed for a landscape will depend 

on soil salt concentrations, tolerable levels, 

depth of the root zone, and soil physical properties. 

To determine an appropriate leaching fraction, it is 

recommended that managers consult with a qualified 

soil laboratory. The leaching fraction will add 

water to that needed for plants (ETL), and the total 

water applied (TWA) will increase. 

Reclaimed Water 

The use of reclaimed water in landscape irrigation 

is becoming more common. Reclaimed water varies 

in quality, however, depending on the source 

and treatment process. Some reclaimed water is of 

high quality with little potential to injure plants. In 

other cases, reclaimed water may be of low quality, 

containing injurious levels of salts or specific elements. 

When irrigating with reclaimed water, planners 

and managers will need to assess and monitor 

water quality. Some upward adjustments in water 

estimates may be needed to reduce plant injury potential 

with low quality water. Consult a qualified 

laboratory when making such adjustments. 

When irrigating with reclaimed 

water, planners and managers will 

need to monitor water quality. 

When irrigating with low quality 

reclaimed water, upward adjustments 

in water budgets may be 

needed to reduce the potential of 

plant injury. 

38

Chapter 8— 

Special Planting 

Situations 

A landscape coefficient (KL) calculation for a new 

planting was made in “Using the Landscape Coefficient 

Formula” (Chapter 3, example 7). In the example, 

a kd value of 0.5 was used which produced a 

KL of 0.1 (ks = 0.2, kmc = 1.0). 

Although the application of the landscape coefficient 

method has been described for many landscape 

cases, there are some special planting situations that 

require further consideration. These cases are described 

in Chapter 8. This concludes the process of 

making water needs estimates for landscape 

plantings. Remember, the appendices contain important 

reference information 

to use in calculations. 

Based on experience, it may be thought that irrigating 

a new planting at one tenth of reference evapotranspiration 

is insufficient. Generally, landscape 

managers believe that new plantings need even more 

water than mature plantings. When irrigation efficiency 

(IE) is considered, however, the amount of 

water needed increases substantially. Indeed, it is 

New plantings, trees in 

turf, individual plants, 

vines, and herbaceous 

plants represent special 

cases which require further 

consideration in making 

water needs estimates. All 

are common elements of 

landscapes. 

New Plantings 

In terms of irrigation water 

needs, the key differences 

between new and 

mature plantings are in 

density factor assignments 

and irrigation efficiency. Typically, canopy cover 

is substantially less in a new planting and the lowest 

kd value, 0.5, is appropriate. Irrigation efficiency 

is also typically low for new plantings. 

New landscape plantings require special consideration. The actual amount of water needed to 

maintain health and appearance in new plants is lower than that needed for established plantings 

(mainly because the density factor is low). However, irrigation efficiency losses are usually very high in 

new plantings, and the total amount of water needed may be equivalent to that of established 

plantings. 

because of very low efficiencies when irrigating new 

plantings that the total amount of water is much 

greater than that needed solely for the plants. 

A sample calculation helps to show the role of irrigation 

efficiency in new planting irrigation. Using 

example 7, ETL = 0.1 for a new planting in Monterey 

39

County in July. The total amount of water needed 

is calculated using the TWA formula: 

TWA = ETL 

IE 

Selecting an irrigation efficiency of 10%, 

TWA = 0.1 = 1.0 inch 

0.1 

Ten times more water needs to be applied than that 

actually needed for the plants. This is based on a 

10% irrigation efficiency for a new planting which 

is sprinkler irrigated. An IE of 10% is reasonable 

because most of the root mass of new plantings is 

confined to the rootball, with available water consisting 

of only that held in the rootball and, in some 

cases, a small volume of adjacent soil. Sprinklers 

deliver water to the entire planted area, not just the 

rootballs, so much of the water falls outside the usable 

area. 

has some root mass, then water landing on half the 

area potentially may be absorbed by plants. In this 

case, irrigation efficiency has increased 5-fold to 

50% (assuming no loss from runoff, evaporation, 

etc.). 

It should be recognized that sprinkler irrigation of 

new plantings (i.e., of container grown plants) is 

not efficient. Other methods should be considered 

for water conservation purposes. Drip systems deliver 

water directly to rootballs and, therefore, have 

higher efficiency. Potentially, hand watering is also 

more water efficient than sprinkler irrigation, provided 

it is done carefully. 

For instance, in a planting area of 100 sq. ft., only 

10 sq. ft. may be occupied by rootball. Thus, if water 

is distributed uniformly, only 10% of the water 

applied falls in the root zone, which produces a 10% 

irrigation efficiency. 

Irrigation efficiencies for some new plantings may 

be even less than 10%. If a planting is sparse and 

root zone occupies less than 10% of the irrigated 

area, and/or some of the water that lands on the 

rootball is lost to evaporation, percolation, or runoff, 

then IE may be less than 10%. 

As roots develop into the adjacent soil, however, 

irrigation efficiency increases rapidly. For instance, 

if after one year, roots have developed into the adjacent 

soil to the point that half the planting area 

The water needs of most tree species planted in turf are generally 

met by the relatively high water needs of turf. Trees with relatively 

high water needs, such as these white alder (Alnus rhombifolia), 

should be used in turf areas. 

40

As root development increases into the adjacent soil, 

sprinkler irrigation efficiency increases, while drip 

irrigation efficiency may actually decrease if emitters 

are not moved or supplemented to supply the 

larger root zone. Dual systems of both drip emitters 

and sprinklers may have the greatest potential 

for maximizing efficiency for new and developing 

plantings: the drip system being used for the new 

planting and the sprinklers employed once the root 

system has developed. 

Trees in Turf 

The water needs of most tree species planted in turf 

are generally met by the relatively high water needs 

of turf. Turf crop coefficients range from 0.6 (warm 

season species) to 0.8 (cool season species). This 

range is sufficient to satisfy the needs of all trees in 

the moderate, low, and very low WUCOLS categories. 

Trees in the high category may need supplemental 

water, particularly if they are planted in warm 

season turf. Trees in cool season turf are not likely 

to need supplemental water. 

some cases, but there will be a greater potential 

for injury. 

2. New Turf Around Established Trees. When 

new turf (and associated irrigation) is installed 

around established trees, precautions are needed 

to avoid injury to the trees. This is particularly 

the case for trees that were not formerly irrigated. 

By supplying water to the root zone of 

established trees the potential for injury from 

disease or poor aeration increases substantially. 

Certain species (e.g., oaks) are more sensitive 

to such changes than other species. The root 

crown area is particularly sensitive and needs 

Aside from meeting total water needs, some other 

factors need to be considered regarding trees in turf: 

1. Species Selection. Not all tree species can be 

expected to perform well in turf. Species in the 

low and very low WUCOLS categories may be 

injured or killed by turf irrigation. Many species 

are adapted to dry summer conditions (e.g., 

oak species) and frequent irrigations associated 

with turf may result in root injury, typically from 

disease or poor aeration. Species selection is 

very important. When specifying trees in turf, 

species should be limited largely to those classified 

as “high” on the WUCOLS list. Species 

from the “moderate” category may be used in 

In times when the water supply for turf becomes restricted (e.g., 

drought years), the water needs of trees in turf may not be met. 

These white birch (Betula pendula) died when water was withdrawn 

from the turf during a drought year. Notice that the juniper 

(Juniperus sp.) were not injured. 

41

special consideration. To help ensure the survival 

of both the turf and trees in this situation, 

it is recommended that a certified arborist be 

consulted. 

3. Drought Years. In times when the water supply 

for turf becomes restricted (e.g., drought years), 

the water needs of trees in turf may not be met. 

During previous droughts in California, many 

trees in turf areas were severely injured or killed 

when water was withheld from turf. Frequently, 

the turf recovers when irrigation resumes, but 

the trees do not. It is very important to provide 

water directly to trees during such times. 

4. Newly-Planted Trees. Water supplied to meet 

turf needs is often not sufficient for newly 

planted trees in turf. Although turf irrigation is 

likely sufficient for most species once established, 

newly planted trees have special requirements. 

In most cases after planting, the roots of 

new trees are confined to the rootball, or a relatively 

small volume of soil. Much of the water 

supplied in turf irrigation (typically via sprinklers) 

does not rewet the rootball sufficiently. 

It is only the water that lands on the rootball 

that can be absorbed, and in most cases this is 

not adequate to meet the needs of the tree. As a 

result, many trees are very slow to develop in 

turf, and some are injured or killed. Supplemental 

water (delivered manually or by drip systems) 

are strongly recommended for trees in turf. 

In addition to special water needs, newly planted 

trees in turf also may be inhibited biologically 

by the turf. This is an effect known as “allelopathy,” 

where one plant inhibits the development 

of another by the release of phytotoxic materials 

from its roots. Turf species are recognized 

as having allelopathic effects on young 

trees and, therefore, an area (2 ft. radius) around 

newly planted trees should be kept turf-free. 

Ideally mulch is applied to the soil surface in 

the turf-free zone to reduce evaporation and 

minimize the potential for mower or trimmer injury. 

5. Shallow Rooting and Windthrow. Turf irrigation 

typically supplies water to the surface 3 to 

6 inches of soil, the active root zone for most 

turf species. Consequently, turf irrigations are 

relatively shallow and frequent (i.e., when compared 

to tree irrigation depths of 1 to 3 ft.). As a 

result, tree roots in turf areas tend to develop 

close to the soil surface. There has been some 

concern regarding the potential for reduced anchorage 

associated with shallow root systems 

of trees in turf. It is thought that large trees may 

have a higher potential for windthrow. Although 

this occurrence has been observed, there is no 

documentation to show that the potential for tree 

windthrow is higher in turf than elsewhere. Nevertheless, 

it is generally held that deep irrigations 

for trees in turf are beneficial. They not 

only increase the potential for root development 

deeper in the soil profile, but they also increase 

the size of the soil volume from which roots can 

extract water. 

Individual Plants 

To this point, the landscape coefficient method has 

been used to estimate water needs of plantings (i.e., 

groups of plants). It also can be used to estimate 

water needs of individual plants. The three factors 

(species, density, and microclimate) are used to determine 

a landscape coefficient as before. A few 

42

considerations apply for individual plants, however, 

and they are discussed for shrubs and trees separately. 

Shrubs 

ks: Species factor values are found in the 

WUCOLS list. 

kd: 

For most shrubs, an average density factor 

of 1.0 will be appropriate. For very large 

shrubs, an upward adjustment to 1.1 may be 

warranted. 

kmc: 

In most cases, the microclimate factor would 

be assigned as discussed in Chapter 2. 

Trees 

ks: 

Species factor values are found in the 

WUCOLS list. 

kd: For small trees (< 15 feet tall), an average 

density factor of 1.0 would be appropriate. 

For larger trees, an upward adjustment to 1.1 

or 1.2 accounts for the increase in leaf area 

found in many canopies. 

kmc: 

In most cases, the microclimate factor would 

be assigned as discussed in Chapter 2. For 

large trees, however, an upward adjustment 

to 1.2 or 1.3 to account for wind flow through 

the canopy may be appropriate. 

Example: The urban forester for the city of Modesto 

is interested in estimating water needs for a large 

Modesto ash tree located in a downtown city plaza 

for the month of July. 

Water needs for individual trees or shcubs can be estimated using 

the landscape coefficient method. Species, density and microclimate 

factors all need to be considered. 

First, the forester needs to assign values for each of 

the landscape coefficient factors. In the WUCOLS 

list Fraxinus velutina ‘Modesto’ is classified as 

“moderate” with a ks value of 0.4. Since this is a 

large, dense tree, the forester uses a density factor 

value of 1.1. The microclimate in the plaza warrants 

a “high” microclimate factor value. In addition, 

the forester wants to adjust for wind flow 

through the canopy since no trees or buildings are 

nearby to attenuate the wind. The forester selects a 

kmc value of 1.5. Using these values, a calculation 

of the landscape coefficient can be made. 


KL = 0.4 x 1.1 x 1.5 = 0.66 

43

A species factor range of 0.4 to 0.8 is suggested to be appropriate for most annual species. 

With the landscape coefficient calculated, the landscape 

evapotranspiration formula is used to calculate 

ETL: 


KL = 0.66 

ETo = 8.0 inches (for July in Modesto) 

ETL = 0.66 x 8.0 inches = 5.28 inches 

The urban forester has estimated that the tree needs 

5.28 inches of water for the month of July to maintain 

good appearance, health, and growth. A further 

adjustment to this value is needed to account 

for irrigation efficiency (see Chapter 5). 

occur on walls, trellises, arbors, 

poles, or on the 

ground. Water needs evaluations 

for many vine species 

are included in the 

WUCOLS list. Although 

the microclimate factor 

(kmc) will not be affected by 

the presence of vines, the 

density factor (kd) is affected. 

Vines add another 

vegetation type or tier (in 

some cases) to a landscape 

and, therefore, increase the 

vegetation density. They 

also may contribute to 

canopy cover. Upward adjustments in kd are likely 

needed when vines are present. These can range 

from small increases (0.1) to large (0.3) depending 

on the amount of vegetation (leaf area) added. 

An alternative method for estimating water loss from 

an individual tree is described in Lindsey and Bassuk 

(1991). This method uses leaf area index (LAI) to 

account for density differences in tree canopies. 

Vines 

Vines occur in many landscapes and need to be considered 

in water loss estimates. Vines can contribute 

substantial leaf area to a planting whether they 

Annuals 

Estimates of water needs for plantings of annual 

species can be made using the landscape coefficient 

formula. As for woody plantings, values for KL and 

ETo are needed. ETo values are obtained as described 

previously, while KL needs to be calculated 

from the three factors, ks, kd, and kmc. The microclimate 

factor, kmc, is determined as before, and kd 

will range from 0.5 to 1.0 depending on the fullness 

of the plantings. The species factor, ks, is more difficult 

to determine as many species are not included 

in the WUCOLS list. Generally, the water requirements 

of annual plants are relatively high and a ks 

range of 0.4 to 0.8 is suggested for most species. 

By assigning values for ks, kd, and kmc, the landscape 

coefficient, KL, can be calculated and an estimate 

of water needs (ETL) is determined. 

44

Part 2 

WUCOLS III* 

1999 Edition 

L. R. Costello 

University of California 

Cooperative Extension 

K.S. Jones 

University of California 

Cooperative Extension 

*WUCOLS is the acronym for Water Use Classification of Landscape Species. 

The WUCOLS list is intended solely as a guide to help landscape professionals identify irrigation 

water needs of landscape species. It can be used either for the selection of species or to assist in 

developing irrigation schedules for existing landscapes. It is not intended to be used as a “required,” 

“mandatory,” “approved,” or “master” list by local, regional, or statewide governments, government 

agencies, or water authorities for the selection of plant species. This list should not be used in 

part or in entirety to restrict species selection only to those species listed here. 

In addition, the evaluations of irrigation water requirements presented here should not be considered 

absolute and are not intended to be used as such, i.e., the user is not “required” to use these evaluations. 

This is a guide to species water needs. 

45

PROJECT PARTICIPANTS 

Project Leader 

L. R. Costello, Environmental Horticulture Advisor 


San Mateo and San Francisco Counties 

Project Coordinator 

K. S. Jones, Horticulture Associate 



REGIONAL COMMITTEES 

North-Central Coast 

Barrie D. Coate, Horticultural Consultant—Barrie D. Coate & Associates, Los Gatos, 1992, 1994,1999* 

Laurence R. Costello, Horticulture Advisor—UC Cooperative Extension, San Mateo and San Francisco Counties 1992, 1994, 1999 

Katherine S. Jones, Horticulture Associate—UC Cooperative Extension, San Mateo and San Francisco Counties 1992, 1994, 1999 

James MacNair, Horticultural Consultant—MacNair & Associates, Glen Ellen, 1992, 1994, 1999 

Nelda Matheny, Horticultural Consultant—Hort Science, Inc., Pleasanton 1992 

John Meserve, Horticultural Consultant—Santa Rosa, 1999 

Tony Norris, Parks and Landscaping Superintendant—City of Richmond, 1999 

Linda Novy, President & C.E.O.—Gardener's Guild, Inc., San Rafael, 1992 

Richard Sealana, Land Management Consultant—Sealana Associates, Fremont, 1992, 1994, 1999 

Dan Sheehy, Area Manager—Cagwin & Dorward, Inc., Novato 1992, 1994, 1999 

M. Nevin Smith—Suncrest Nurseries, Watsonville, 1999 

Central Valley 

Fred Allen, Landscape Architect—City of Modesto, 1992 

Ralph Carhart, Landscape Architect—CalTrans, Division of Maintenance, Sacramento 1992 

Ann Chandler, Owner—Cornflower Farms Nursery, Elk Grove 1992 

Pam Elam Geisel, Farm Advisor—UC Cooperative Extension, Fresno County,1992, 1994, 1999 

Larry Fitzgerald, former Container Production Manager—Oki Nursery, Sacramento, 1992 

Gary Hickman, Farm Advisor—UC Cooperative Extension, San Joaquin County, 1992, 1999 

Martin Hildebrandt—Scenic Nursery, Modesto, 1999 

Ed Perry, Farm Advisor—UC Cooperative Extension, Stanislaus County, 1992, 1994, 1999 

Lance Walheim, Horticultural Consultant—Exeter, 1992 

South Coastal 

Randy Baldwin, General Manager—San Marcos Growers, Santa Barbara, 1992, 1994 

Jeff Cope—City of Santa Barbara, 1999 

Cynthia Drake, Horticultural Consultant—San Diego, 1999 

Scott Molentin, Landscape Architect—Estrada Land Planning, San Diego, 1992, 1994 ,1995 

Wesley A. Humphrey, Horticultural Consultant—Fallbrook, 1992, 1994, 1999 

Frederick M. Lang, Landscape Architect—South Laguna,1992 

Lynn Ocone, Garden Writer—Sunset Magazine, Los Angeles 1992 

Rick Mosbaugh, President—Statice Landscape Inc., Los Angeles 1992, 1994 

Ray Sodomka, Owner—Turk Hesselund Nursery, Montecito, 1992, 1994, 1999 

Tom Larson—Integrated Urban Forestry, Laguna Hills, 1992, 1994, 1999 

South Inland 

Mike Evans, Partner—Tree of Life Nursery, San Juan Capistrano 1992, 1994 

Michael MacCaskey, Garden Writer—Sunset Magazine, Los Angeles, 1992 

L. K. Smith, Landscape Architect—Newbury Park, 1992, 1994, 1995 

Kenneth K. Kammeyer, Landscape Architect—Kammeyer & Associates, Corona ,1992, 1994, 1999 

High & Low Desert 

Ronald L. Baetz, Administrative Services Officer—Desert Water Agency, Palm Springs, 1992 

Jerry Clark, Landscape Architect—City of Palm Desert ,1999 

William Deady, Horticultural Consultant—Morongo Valley, 1992, 1994 

David Harbison, Water Management Specialist—Coachella Valley Water District, Coachella, 1992, 1994, 1999 

Eric Johnson, Desert Landscape Consultant—Palm Desert, 1992, 1994 

Bob Perry, Landscape Architect—Claremont ,1992, 1994, 1999 

Ruth Watling, Horticultural Consultant—Mountain Center, 1999 

* Year(s) of participation on WUCOLS Committee 

46

REGIONAL COMMITTEES 

1992 

Front: B. Coate, R. Sealana 

Back: R. Carhart, G. Hickman, J. MacNair, K. Jones, D. Sheehy, 

N. Matheny, L. Walheim, P. Geisel, E. Perry, F. Allen, A. Chandler, 

L. Novy, L. Fitzgerald, L. Costello 

Front and kneeling: F. Lang, K. Smith, T. Larson, R. Perry, L. 

Ocone, L. Costello 

Back: W. Humphrey, S. Molentin, R. Sodomka, K. Smith, 

M. MacCaskey, M. Evans, R. Baldwin 

Left to right: R. Perry, E. Johnson, W. Deady, K. Jones, R. Baetz, 

D. Harbison 

1998 

Front: R. Sealana, K. Jones 

Back: L. Costello, J. MacNair, J. Meserve, M. Hildebrandt, 

G. Hickman, N. Smith, P. Geisel, E. Perry 

Absent from photo: B. Coate, T. Norris, D. Sheehy 

Left to right: R. Watling, K. Jones, W. Humphrey, C. Drake, 

R. Perry, J. Cope, K. Smith, D. Harbison, R. Sodomka, J. Clark, L. 

Costello, S. Molentin, K. Kammeyer 

47

Introduction 

Water conservation is an essential consideration in 

the design and management of California landscapes. 

Effective strategies that increase water use 

efficiency need to be identified and implemented. 

One key strategy to increase efficiency is that of 

matching water supply to plant needs. By supplying 

only the amount of water needed to maintain 

landscape health and appearance, unnecessary applications 

that exceed plant needs can be avoided. 

To do so, however, requires some knowledge of 

species needs. 

This Guide provides irrigation water needs evaluations 

for over 1,900 species used in California landscapes. 

It is based on the observations and field 

experience of 41 knowledgeable landscape horticulturists 

in California (see list of Regional Committees). 

It was developed to provide guidance in 

the selection and maintenance of plants based on 

irrigation water needs. Specifically, it can be used 

to: 

• assist landscape architects, designers, and planners 

in selecting plants for water efficient landscapes, 

• assist landscape managers in evaluating water 

needs of existing plantings and in creating irrigation 

schedules that match species needs, 

• provide options for landscape managers who wish 

to create hydrozones, i.e., to change species composition 

to reduce wide variations in water needs 

within plantings, and 

The WUCOLS guide provides water needs evaluations for over 

1900 species. Plants can be selected according to their water 

needs and grouped into water conserving hydrozones. 

• provide a basis for estimating water needs for new 

landscapes. 

The project was initiated and funded by the Water 

Use Efficiency Office of the California Department 

of Water Resources. Work was directed by the University 

of California Cooperative Extension (San 

Francisco and San Mateo County office). The first 

edition of the Guide was completed in 1992. A second 

edition was published in 1994, and this third 

edition was completed in 1999. In each edition, additional 

species evaluations have been included. The 

third edition was funded by the U.S. Bureau of Reclamation. 

49

Getting Started 

If you are using the Guide for the first time, we suggest 

you begin by reading the following sections on 

“Categories of Water Needs”, “Standard Conditions”, 

“Plant Types”, and “Regions”. These sections 

contain background information which is 

needed to use the Guide effectively. 

If you have used the Guide before, and are familiar 

with the terms and the evaluation process, proceed 

directly to “Species Evaluations,” page 62. Be advised, 

however, that new information has been introduced 

in WUCOLS III. 

How do I calculate the right amount of irrigation 

water to apply? 

See “Part 1” of this guide. 

Is there more to know? 

See “Other Important Information About the Guide,” 

page 59 and “Appendix B, Invasive Species,” 

page 143. 

The following will help you locate information on 

important topics. 

Cotinus coggygria, smoke tree, Low 

What does High, Moderate, Low and Very Low 

mean? 

See “Categories of Water Needs,” page 52. 

What are Standard Conditions? 

See “Standard Conditions,” page 53. 

What is meant by Plant Types ? 

See “Plant Types,” page 55. 

What is meant by Regions? 

See “Regions,” page 56. 

51

Categories of Water Needs 

The key question addressed by WUCOLS committee 

members was the following: 

In order to be maintained in good condition, in 

the region of California being considered, and 

under the standard conditions outlined, does the 

species need high, moderate, low, or very low 

amounts of irrigation water? 

This question served as the starting point for the 

evaluation process. After defining the terms “Regions” 

and “Standard Conditions” (see following 

sections), species were evaluated as needing High, 

Moderate, Low, and Very Low amounts of irrigation 

water. Expressed as a percentage of reference 

evapotranspiration (ETo), these categories were 

quantitatively defined as follows: 

High (H) = 70 - 90% ETo 

Moderate (M) = 40 - 60% ETo 

Low (L) = 10 - 30% ETo 

Very Low (VL) =

assessment of species needs. If there is variation 

among regions for a species, looking at all evaluations 

for the species can help you select an irrigation 

level at the high or low end of the category's 

range. 

Standard Conditions 

The following conditions were applied to all species 

evaluations. 

Cerastium tomentosum, snow in summer, Medium 

Evaluations for Zexmenia hispida: 

• Regions 1, 2, 3, 4, 5 and 6……? committee members 

did not know species water needs 

NOTES: 

1. Reference evapotranspiration (ETo) is defined in 

“Standard Conditions.” 

2. Cases where there are question marks in several 

regions usually indicate plants that are new to 

the nursery trade in California. Consult horticultural 

literature for more information about species 

water needs. 

It is helpful to look at all the evaluations for each 

species, (i.e., for all six regions) to get a general 

Established Plants 

Species irrigation water needs are assessed for plants 

that have become “established” in the landscape. 

“Established” meaning that substantial root development 

has occurred in the landscape soil adjacent 

to the rootball. The landscape soil becomes the principal 

source of water for established plants rather 

than the rootball soil. The time for establishment 

varies among species and with soil conditions, but 

generally occurs by the second or third year after 

planting. After establishment, roots of trees, shrubs, 

groundcovers, etc., become intertwined in the soil, 

creating a common rootzone. 

Reference Evapotranspiration Conditions 

(ETo) 

ETo is defined as water loss from a large field of 

4-to-7-inch-tall, cool-season grass that is not water 

stressed. Although ETo can be measured directly, it 

is usually calculated from weather data. Daily ETo 

information for many regions of the state is available 

through the California Irrigation Management 

Information System (CIMIS). Evaluations are made 

for site conditions equivalent to those used for ETo 

measurements, i.e., full sun, no extraordinary winds, 

no shading from nearby structures or plants, and no 

heat inputs from nearby sources such as buildings, 

pavements, or reflective surfaces. As an exception, 

53

shade-requiring species (e.g., Japanese aucuba) are 

evaluated for shade conditions. Shade species are 

considered to be those plants which when exposed 

to full sun for some part of the day will show visible 

injury. Since species vary in their shade requirements 

(for example, all day versus afternoon 

shade), any species requiring some shade to avoid 

injury (in the region) is evaluated for shade. 

See “Appendix D, Additional Resources,” for information 

on how to obtain CIMIS data. 

Good Quality 

Plant performance can vary substantially depending 

on the amount of water supplied. Small amounts 

may simply prevent the dehydration of plant tissues, 

but appearance is likely to be affected. Increasing 

amounts may improve appearance (leaf color, 

canopy density or fullness), but may not be enough 

to promote growth. More water may be sufficient 

to maintain good appearance and support typical 

(average) growth for the species (and flower or fruit 

production if desired). Still more water may result 

in excessive growth; while more water may cause 

decline (typically from root disease) in certain species. 

Since both appearance and some growth (not 

excessive) are important in most landscapes, evaluations 

were made to provide sufficient water for the 

species to be maintained as such, i.e., in good condition. 

This is somewhat difficult to evaluate precisely 

for some species, however, so whenever a 

question was raised as to whether a species required 

a greater or lesser amount of water to maintain good 

quality, the higher evaluation (more water) was assigned. 

Groundwater Not Available 

Although some species of plants develop root systems 

deep enough to extract groundwater (e.g., 

Quercus lobata), groundwater is not available in all 

planting sites. A species capable of extracting 

groundwater may not be able to do so because the 

water is simply not available. Therefore, evaluations 

are made for conditions where the only sources 

of water were rainfall and irrigation. In areas where 

groundwater is available and a species is known to 

utilize ground water, then adjustments in irrigation 

scheduling should be made for that species (or group 

of species). 

Plants Must Be Irrigatable 

In some cases the soil surface may be sealed around 

plants (particularly trees) by pavements or other 

surface barriers. This inhibits the infiltration of water 

into the rootzone. In other cases the soil volume 

capable of holding water may be so small and may 

dry so rapidly that it may be difficult to maintain 

available water in the rootzone. In either case, the 

amount of water identified as being needed to maintain 

good quality may not be sufficient simply because 

the plant is not “irrigatable.” Evaluations 

made here assume as a standard condition that the 

species can be irrigated, i.e., the water applied can 

enter and be held in the rootzone sufficiently long 

for uptake. 

54

Plant Types 

The species list includes over 1,900 species of landscape 

plants which are identified by botanical and 

common names. The plants are listed alphabetically 

according to botanical names. An index of common 

names follows the species list. 

Each plant falls into one or more of the following 

vegetation types: Trees, Shrubs, Groundcovers, 

Vines, Perennials (includes ferns, grasses, and bulbs) 

and Biennials. Plant types are entered on the list 

for each plant under “Type” as: 

T......... Tree 

S......... Shrub 

V......... Vine 

Gc...... Groundcover 

P......... Perennial 

Bi….... Biennial 

Cultivars, with some exceptions, are not mentioned. 

It is presumed that most cultivars will have the same 

water requirements as the species. Examples of exceptions 

include the following: 

1. Nandina domestica the cultivar ‘Purpurea’ was 

included because it was thought to require more 

water than the species in three regions, 

2. Lonicera japonica ‘Halliana’ was included because 

the cultivar was thought to be more common 

than the species, 

3. Illicium floridanum ‘Alba’ was included because 

it was the only example of the species listed. 

Turfgrasses 

Turfgrasses were not evaluated by the committee. 

For your convenience, several turf species are listed 

in the “Species Evaluations” section. Water use requirements 

listed are from University of California 

Publication 21491, Turfgrass Evapotranspiration 

Map, Central Coast of California. This publication 

also contains other important information regarding 

turfgrass irrigation such as regional ET variability, 

correcting for rainfall, dew, and fog and calculating 

sprinkler run times. 

Rosa sp. climbing rose, High to 

Medium and Solanum jasminoides, 

potato vine, Medium 

55

Regions 

Since there are substantially different climate zones 1 

in California, species are evaluated for six regions 

which represent different climatic conditions. 

Region 1 

North-Central Coastal (California Climate Zones 14, 

15, 16, and 17) (CIMIS ETo Zones 1, 2, 3, 4, 6 and 8) 2 

Region 2 

Central Valley (California Climate Zones 8, 9 and 

14), (CIMIS ETo Zones 12, 14, 15, and 16) 

Region 3 

South Coastal (California Climate Zones 22, 23 and 

24), (CIMIS ETo Zones 1, 2, 4 and 6) 

Region 4 

South Inland Valleys and Foothills (California Climate 

Zones 18, 19, 20 and 21), (CIMIS ETo Zone 9) 

Region 5 

High and Intermediate Desert (California Climate 

Zone 11), (CIMIS ETo Zones 14 and 17) 

Region 6 

Low Desert (California Climate Zone13), (CIMIS 

ETo Zone 18) 

___________________ 

1 

California climate zones are described in University of California 

Publication 3328, Generalized Plant Climate Zones 

of California and Sunset Western Garden Book. 

Notes on Regions 

Within each region there is some variability in climate 

patterns among the cities listed. For example, 

some cities may be considerably warmer than others 

during the summer months, yet they are within 

the same region. This variability can only be reduced 

by increasing the number of regions, which 

would cause the list to become enlarged and somewhat 

more complicated. 

For certain locations (considered atypical for the 

region), it may be useful to consider evaluations 

from another region that more closely characterizes 

the location of interest. For example, if a city in 

Region 1 has a climate more closely characterized 

by Region 2, then Region 2 species evaluations 

should be considered for that location. Such assessments 

will need to be based on the judgement of the 

user. 

If a city is not listed and is located in California 

Climate Zone 14 which overlaps regions 1 and 2, it 

will be necessary to decide if the city is more similar 

in climate to Petaluma (coastal influence) or 

Sacramento Valley. 

If a city is located in a California Climate Zone 

which was not evaluated (zones 1, 2, 3, and 7— 

mainly high elevation, cold winter areas) an estimate 

may be made by looking at all the evaluations 

for the species in question. Hardiness is typically 

the major factor in determining if a species is appropriate 

or not. 

2 

ETo Zones are described in the California Irrigation Management 

Information System (CIMIS) Reference Evapotranspiration 

Map, 1999 (see map on page 141). 

The main difference between the California high and 

intermediate desert regions is that the high desert is 

colder in the winter; as the elevation increases so 

does the frequency of temperatures below freezing. 

56

As a result, species which are listed as appropriate 

for the low desert and inappropriate for the high 

desert may be marginally hardy and appropriate to 

try in the intermediate desert. 

Some Cities that Characterize Each Region 

REGION 1 REGION 2 REGION 3 

North-Central Central Valley South Coastal 

Coastal 

Concord Auburn Anaheim 

Cupertino Bakersfield Camarillo 

Healdsburg Chico Fallbrook 

Livermore Coalinga Fullerton 

Los Altos Hills Fresno Irvine 

Napa Los Banos Laguna Beach 

Novato Marysville La Mesa 

Oakland Merced Long Beach 

Petaluma Modesto Los Angeles 

Salinas Red Bluff Mission Viejo 

San Francisco Redding Oxnard 

San Jose Roseville Santa Ana 

San Luis Obispo Sacramento Santa Barbara 

Santa Cruz Stockton San Diego 

Santa Rosa Tracy San Juan Capistrano 

Visalia Santa Monica 

Ventura 

Vista 

Whittier 

REGION 4 REGION 5 REGION 6 

South Inland Intermediate Low Desert 

Valley & High Desert 

Altadena Apple Valley Borrego Springs 

Azuza Barstow Blythe 

Chino Bishop Brawley 

Corona Boulder City Coachella 

Covina China Lake Desert Center 

El Monte Gorman Desert Hot Springs 

Escondido Independence Death Valley 

Hemet Joshua Tree El Centro 

Ojai Lancaster Indian Wells 

Pasadena Lone Pine Indio 

Perris Mojave Jacumba 

Pomona Olancha Needles 

Ramona Palmdale Palm Desert 

Riverside Pear Blossom Palm Springs 

San Bernardino Tehachapi Rancho Mirage 

San Fernando Victorville Thermal 

Santa Paula 

Sun City 

Thousand Oaks 

Van Nuys 

Cistus purpureus, orchid rockrose, 

Low to Very Low 

57

Other Important 

Information About 

the Guide 

Variation in Regional Evaluations 

Variation in species evaluations among regions occurs 

in many cases. Two patterns of variation are 

found: 

1. where the variation ranges from less water 

needed in cooler climates to more in warmer 

ones, and 

2. where less water is required in warmer climates 

than in cooler ones. 

The following examples are typical cases: 

Case 1— Laurus nobilis, sweet bay 

1 2 3 4 5 6 

L L L L M M 

This is the most common variation. It merely indicates 

that certain species were thought to require 

more water in warmer climates. 

Case 2—Gleditsia tricanthos, honey locust 

1 2 3 4 5 6 

L L M L L L 

A warmer region indicates a lower water requirement 

than a cooler region. This case reflects differ- 

ences in observation and experience among regional 

committees. 

Zauchneria spp., California fuchsia 

1 2 3 4 5 6 

L L VL L / M 

This example shows both cases. Sometimes, for 

certain California natives and other drought tolerant 

species, there was agreement that the plant would 

grow with little or no irrigation, but opinions varied 

as to how well it would perform in a managed landscape 

under those conditions. 

Drought Stress/Insect Attack Relationships 

Although some species perform well with little or 

no irrigation water, their susceptibility to insect attack 

and injury may increase with water stress. For 

example, many Eucalyptus species perform well in 

non-irrigated conditions in many parts of California. 

When drought stressed, however, they become 

susceptible to attack and injury from the Eucalyptus 

long-horned borer. This is the case as well for 

Monterey pine (California five-spined engraver 

beetle) and white alder (Flatheaded borer). For these 

species, evaluations were made with consideration 

given to water stress and pest interactions. For example, 

although Eucalyptus globulus will perform 

well in Regions 3 and 4 with little summer water, it 

was assigned to the “moderate” category to minimize 

its susceptibility to borer injury. 

Shade 

Most species were evaluated for full sun conditions. 

Light intensity and duration varies with seasons, 

microclimates and proximity to the coast. Many 

59

species which can be grown in full sun in coastal 

locations require a measure of shade in inland areas. 

Others require some shade in all locations. Here, 

each species was evaluated for the conditions which 

would produce best appearance and flowering or 

fruit production for the region. Because of the lack 

of a standard method for identifying species shade 

requirements, however, plants needing shade are not 

Summer Deciduous Species 

As a drought adaptation, certain species shed their 

leaves when soil moisture level become low (e.g. 

California buckeye). Usually, such species do not 

require irrigation water and are designated Very Low 

on the list. In cases of low spring rainfall, or when 

retention of summer leaves is desired, irrigation may 

be needed. 

Special Conditions 

Special conditions such as 

new plantings or a need for 

rapid growth may require 

upward adjustments in species 

water needs. 

Rhus lancea, African sumac, Medium to Low 

noted on the list. Consult horticultural literature for 

more information on species light requirements. 

Revegetation Species 

Species selected for revegetation 

sites should be limited 

to those which are well 

adapted to the location and 

do not require irrigation after 

establishment. Species 

used principally for revegetation 

(i.e., not typically 

used in irrigated landscape, such as mule fat and 

poison oak) are not included on the species list. 

Winter Irrigation 

Although deciduous species are not typically irrigated 

in the winter months, there may be some need 

to do so in desert regions. Warm, windy conditions 

can dehydrate shoots and buds. In addition, some 

evergreen species may need winter irrigation during 

drought years or in desert climates. 

Invasive Species 

Certain species considered invasive both in wildland 

areas and managed landscapes are available in 

California nurseries. Their inclusion on this list is 

not meant to encourage their use, but to alert you 

that these species can be invasive. For detailed information, 

see “Invasive Species” (Appendix B). 

60

Using Field Data 

Although substantial information exists on the irrigation 

water needs of agricultural species and 

turfgrasses, little information is available for woody 

and herbaceous landscape species. Field studies 

have quantified the irrigation requirements for six 

groundcover species (Pittenger, 1990) and three tree 

species (Hartin, 1991). This information has been 

used in these evaluations. Considering that over 

1,900 tree, shrub, groundcover, vine, and perennial 

species are available from California nurseries, however, 

a considerable amount of work still needs to 

be done before field data alone can be used to determine 

species water needs. 

Limitations of the List 

This list is limited in a number of ways: 

1. It is subjective (i.e., it is based largely on field 

observations rather than scientific data). As 

such, evaluations are not definitive and may 

change as more research-based information becomes 

available. 

Astilbe hybrid, false spirea, High to Medium 

2. It is a partial list—not all landscape species are 

included. It is a large list which includes most 

plants available from California nurseries, but 

it does not include all plants. Additions to the 

list are expected as new species are introduced 

or less common species are evaluated. 

3. Not all regions of California are included in the 

evaluations. Extrapolations may be needed from 

a region evaluated to one that is not. 

61

Species Evaluations 

The three plant species listed below are examples 

of entries on the Species Evaluation List. As a quick 

reference, a key to symbols is included below. For 

more information on terms and the evaluation process, 

see previous sections. 

1 2 3 4 5 6 

T Ailanthus altissima tree of heaven VL VL L L L L ☹ 

S Brugmansia spp. angel’s trumpet M / M H / / 

Gc Dodonaea procumbens hopseed L L L ? ? ? 

Key to Symbols 

CATEGORIES OF WATER NEEDS 

H High 

M Moderate 

L Low 

VL Very Low 

/ Inappropriate 

? Unknown 

WUCOLS REGIONS 

1 North Central Coastal 

2 Central Valley 

3 South Coastal 

4 South Inland Valley 

5 High and Intermediate Desert 

6 Low Desert 

PLANT TYPES 

T Tree 

S Shrub 

V Vine 

Gc Groundcover 

P Perennial (includes ferns, grasses and bulbs) 

Bi Biennial 

INVASIVE SPECIES 

☹☹ Greater Statewide Concern 

☹ Lesser Statewide Concern 

62

Species Evaluation List--1999 

REGIONAL EVALUATIONS 

TYPE BOTANICAL NAME COMMON NAME 1 2 3 4 5 6 INVASIVE 

S Abelia chinensis Chinese abelia M ? ? ? / / 

S Abelia floribunda Mexican abelia M ? M M / / 

S Gc Abelia X grandiflora glossy abelia M M M M / / 

S Abelia 'Sherwoodii' Sherwood dwarf abelia M M M M / / 

T Abies spp. fir M / M M / / 

T Abies pinsapo Spanish fir L / L / / / 

S Abutilon X hybridum flowering maple M H H H / / 

S Abutilon palmeri indian mallow ? ? L ? ? ? 

S T Acacia abyssinica Abyssinian acacia / ? / ? / L 

T Acacia aneura mulga / ? ? ? / L 

T Acacia baileyana Bailey acacia L L L L / / L 

T S Acacia berlandieri guajillo ? ? ? M / L 

T Acacia boormanii Snowy River wattle ? ? L ? ? ? 

T Acacia cognata (A.subporosa) bower wattle L L M M / / 

T S Acacia constricta whitethorn acacia ? L L L L L 

T S Acacia craspedocarpa leatherleaf acacia ? ? ? ? L L 

T Acacia cultriformis knife acacia L L L L / / 

T Acacia dealbata silver wattle VL L L L / / L 

T Acacia decurrens green wattle VL L L L / / L 

T Acacia farnesiana sweet acacia ? ? L L / L 

S Acacia glaucoptera clay wattle L / L L / / 

T S Acacia greggii catclaw acacia L L L L L L 

T S Acacia longifolia Sydney golden wattle L L L L / / L 

T Acacia melanoxylon blackwood acacia VL L L L / / L 

T Acacia pendula weeping acacia L L M M / L 

T Acacia pennatula pennatula acacia ? ? VL ? L L 

T S Acacia podalyriifolia pearl acacia VL VL L M / / 

S Gc Acacia redolens prostrate acacia VL VL L L L L 

S Acacia rigens needleleaf acacia / / ? ? ? ? 

T Acacia rigidula rigidula acacia / / ? ? ? ? 

T Acacia salicina willow acacia L L L M / M 

T S Acacia saligna blue leaf wattle L L L L / M 

T Acacia schaffneri twisted acacia / / ? ? / L 

T Acacia smallii desert sweet acacia / / VL L / L 

T Acacia stenophyla eumong/shoestring acacia VL L L L / L 

T S Acacia subporosa subporosa acacia L / L ? ? ? 

S Acacia vestita hairy wattle ? ? L L ? ? 

T Acacia willardiana palo blanco / / ? L / L 

P Acanthus mollis bear's breech M M M M / M 

T S Acca sellowiana (Feijoa sellowiana) pineapple guava L L L M / M 

T Acer buergerianum trident maple M M M / / / 

T Acer campestre hedge maple M M ? ? / / 

T S Acer circinatum vine maple M H / / / / 

T Acer X freemanii Freeman maple M M ? ? ? ? 

T Acer griseum paperbark maple M M ? ? ? ? 

T Acer macrophyllum big leaf maple M H M H / / 

T Acer negundo box elder M M M M / / 

T Acer oblongum evergreen maple (oblongum) M / M M / / 

T Acer palmatum Japanese maple M M H H / / 

T Acer paxii evergreen maple (paxii) M M M M / / 

T Acer platanoides Norway maple M M / H / / 

T Acer rubrum scarlet red maple M H H H / / 

T Acer saccharinum silver maple M M / M / / 

T Acer saccharum sugar maple M / / / / / 

T Acer tataricum ssp. ginnala amur maple M M ? ? ? ? 

T Acer truncatum Chinese maple M M / H / / 

P Achillea ageratifolia Greek yarrow L M M M M M 

P Achillea clavennae silvery yarrow L L L L / / 

P Achillea filipendulina fern leaf yarrow L L L L M M 

P Achillea X kellerii kellerii achillea M ? L ? ? ? 

P Achillea millefolium & hybrids common yarrow L L L L M M L 

63




Gc P Achillea tomentosa woolly yarrow L L L L M M 

P Aconitum napellus garden monkshood M M / / / / 

P Acorus gramineus sweet flag H H H H H H 

V Actinidia arguta kiwi/Tara M M M ? / / 

V Actinidia deliciosa kiwi H H H H / / 

S Adenanthos drummondii woolly bush ? ? L ? ? ? 

S Adenanthos sericea woolly bush L ? ? ? ? ? 

P Adenophora bulleyana ladybells H ? ? ? ? ? 

P Adenophora liliifolia lilyleaf ladybells H ? M ? ? ? 

S Adenostoma fasciculatum chamise VL VL VL VL / / 

T S Adenostoma sparsifolium red shanks/ribbonwood VL ? VL VL / / 

P Adiantum spp. maidenhair fern H H H H H H 

S P Aeonium spp. Canary Island rose L / L L / L 

T Aesculus californica California buckeye VL VL VL L / / 

T Aesculus X carnea red horsechestnut M M M M / / 

T S Aesculus pavia red buckeye M ? ? ? ? ? 

P Aethionema armenium 'Warley Rose' Warley rose stone cress M ? ? ? ? ? 

T Afrocarpus gracilior (Podocarpus African fern pine M M M M ? M 

gracilior) 

S Agapetes 'Ludgvan Cross' Ludgvan cross agapetes M ? M ? ? ? 

S Agapetes serpens (Pentapetpterygium) agapetes (serpens) M ? M ? ? ? 

P Agapanthus africanus lily-of-the-Nile M M M M / M 

P Agapanthus campanulatus M M M M / M 

P Agapanthus inapertus major L ? M M / M 

P Agapanthus praecox spp. orientalis & 

M M M M / M 

cvs 

P Agastache aurantica giant hyssop M M M M M M 

P Agastache cana mosquito plant M M M M M M 

P Agastache coccinea pink agastache M M M M M M 

P Agastache rugosa wrinkled agastache M M M M M M 

T Agathis australis Australian agathis/ kauri M / M / / / 

T Agathis robusta Queensland kauri M / M M / / 

S P Agave spp. agave L L L L / L 

T Agonis flexuosa peppermint tree L / L M / / 

P Agyranthemum 'Chelsea girl' agyranthemum ? ? M M ? ? 

T Ailanthus altissima tree of heaven VL VL L L L L L 

Gc Ajuga reptans carpet bugle M M M H H H 

V Akebia quinata fiveleaf akebia M M M M / / 

T Albizia distachya plume albizia L / L / / / L 

T Albizia julibrissin silk tree L L M M M M 

T Alectryon excelsus alectryon/titoki M / M / / / 

V Allamanda cathartica golden trumpet vine / / M / / / 

P Allium spp. allium M M M M ? ? 

T Allocasuarina torulosa forest oak L ? ? / ? ? 

T Allocasuarina verticillata (Casuarina coast beefwood L L L L M M 

stricta) 

T Alnus cordata Italian alder M M M M / / 

T Alnus glutinosa black alder M M M H / / 

T Alnus oregona Oregon alder H H / / / / 

T Alnus rhombifolia white alder H H H H H / 

P Alocasia spp. elephant's ear H H H H / / 

T S Aloe spp. aloe L L L L / L 

P Alonsoa warscewiczii alonsoa M ? M ? ? ? 

P Alopecurus pratensis 'Aureus' golden foxtail ? ? M ? ? ? 

S Aloysia machrostachya aloysia ? ? ? ? L L 

S Aloysia triphylla lemon verbena L L L L L L 

S P Alpinia zerumbet shell ginger H / H H / H 

P Alstroemeria spp. Peruvian lily M M M M ? M 

S Alyogyne hakeifolia red centered hibiscus / / L L / / 

S Alyogyne huegelii blue hibiscus L L L L / L 

64




P Alyssum montanum mountain alyssum L L ? ? ? ? 

P Amaryllis belladona naked lady VL VL VL L L L 

S Ambrosia deltoidea triangleleaf bursage ? ? ? ? L L 

S Ambrosia dumosa white bursage ? ? / / L L 

S Amorpha fruiticosa false indigobush ? ? ? ? M ? 

V Ampelopis brevipedunculata blueberry creeper M M / M M M 

P Anaclycus pyrethrum var depressus Mount Atlas daisy ? ? ? ? ? ? 

P Anagallis monellii pimpernel ? ? M / / / 

S Gc Andromeda polifolia bog rosemary H H / / / / 

P Androsace lanuginosa rock jasmine M ? ? ? ? ? 

P Anemone X hybrida Japanese anemone M M M M M M 

P Anemone pulsatilla (see Pulsatilla 

vulgaris) 

P Anemone sylvestris snowdrop windflower ? ? M ? ? ? 

V Anemopaegma chamberlaynii yellow trumpet vine ? ? M M / / 

P Gc Anemopsis californica yerba mansa ? ? ? ? H H 

P Angelonia angustifolia angel flower ? ? M ? ? ? 

T Angophora cordifolia (Angophora gum myrtle L / L M / / 

costata) 

P Anigozanthos flavidus kangaroo paw L L L L / M 

P Anigozanthos viridis green kangaroo paw L L L L / M 

S Anisacanthus spp. desert honeysuckle ? ? L L L L 

S Anisodontea X hypomadarum South African mallow M M M M / M 

S Anisodontea scabrosa false mallow M M M M / M 

T Annona cherimola cherimoya M / M M / / 

P Antennaria rosea pussy toes L L ? ? ? ? 

P Anthoxanthum odoratum sweet vernal grass M ? ? ? ? ? 

Gc V Antigonon leptopus coral vine M / L L / L 

Gc Aptenia cordifolia ice plant (Aptenia) L L L L / H 

GC Aptenia 'Red Apple' ice plant (Red Apple) L L L L / H L 

P Aquilegia spp. columbine L L M M M M 

P Arabis spp. rockcress L M M ? ? ? 

V Araujia sericifera cruel vine ? ? L ? ? ? 

T Araucaria araucana monkey puzzle tree L M / M / / 

T Araucaria bidwilii bunya-bunya L M M M / / 

T Araucaria heterophyla Norfolk Island pine M M M / / / 

T Arbutus 'Marina' Marina arbutus L L M M / / 

T Arbutus menziesii madrone L L / / / / 

T S Arbutus unedo strawberry tree L L L L M M 

T Archontophoenix cunninghamiana king palm M M M M / / 

S Gc Arctostaphylos cultivars manzanita cultivars L L L L / / 

S T Arctostaphylos diversiloba 

summer holly VL L VL L / L 

(Comarostaphylis diversiloba) 

S Gc Arctostaphylos spp. manzanita VL L L L / / 

Gc P Arctotheca calendula cape weed M M M M / M L 

P Arctotis hybrids African daisy M M L L / M 

Gc Ardisia japonica Japanese ardesia, marlberry M / H / / / 

T Arecastrum romanzoffianum (See 

Syagrus romanzoffiana) 

Arenaria spp. (See Sagina) 

Irish, Scotch moss 

P Arenaria montana sandwort ? M M M ? ? 

S Arenga engleri Ryukyu Island palm ? ? M ? ? ? 

P Argyranthemum frutescens Marguerite daisy M M M M / M 

P Aristea ecklonii little Tyler/blue stars M ? M M / / 

P Aristea major tall aristea M ? ? ? ? ? 

V Aristolochia californica California Dutchman's pipe L L ? M / / 

V Aristolochia durior Dutchman's pipe M M ? M / / 

V Aristolochia elegans calico flower / / M M / / 

P Armeria alliacea sea pink 

P Armeria caespitosa (A. juniperifolia) thrift ? ? M M M M 

Gc P Armeria maritima sea pink M M M M M M 

65




P Armeria setacea thrift ? ? M M M M 

P Arnica montana arnica M ? ? ? ? ? 

P Arrhenatherum elatius ssp bulbosum bulb oat grass ? ? M M M M 

S Gc Artemisia spp. (shrubby) sagebrush VL L L L L L 

Gc P Artemisia spp. (herbaceous) tarragon/angel's hair etc. L L L L M M 

P Arthropodium cirrhatum star lily M ? M ? / / 

P Arum italicum Italian Arum VL L VL ? ? ? 

P Arundo donax giant reed M M M M M M L L 

Arundinaria (See Chimonobambusa, 

Drepanostachyum, Pleioblastus, 

Semiarundinaria, Thamnocalamus & 

other genera) 

P Arundinaria gigantea cane reed L L M M / M 

V Asarina antirriniflora (Maurandya) snapdragon vine M ? M ? / M 

V Asarina barclaiana (Maurandya) climbing snapdragon M ? M ? ? ? 

V Asarina erubescens (Maurandya) creeping gloxinia M ? M ? ? ? 

Gc P Asarum caudadum wild ginger M M H ? / / 

P Asclepias tuberosa butterfly weed M M M M M M 

P Asclepias (wild species) milk/silk weed L L L L L L 

P Asparagus spp. ornamental asparagus M M M M / M 

P Asphodeline lutea Jacob's rod/kings spear L ? ? ? ? ? 

P Asphodeline taurica Asphodel L ? ? ? ? ? 

P Aspidistra elatior cast iron plant L L M M / M 

P Asplenium bulbiferum mother fern M M H H / / 

P Asplenium nidus bird's nest fern M M H / / / 

P Asplenium scolopendrium (Phyllitis) Hart's tongue fern L ? L ? ? ? 

P Astelia nervosa chathamica silver spear M / M ? ? ? 

P Astelia nivicola astelia M ? ? ? ? ? 

P Aster spp. aster M M M M M M 

P Asteriscus maritimus gold coin, Canary Island daisy M M L M / / 

P Asteriscus sericeus (See Naupilus 

sericecus) 

P Astilbe hybrids false spirea M H / / / / 

P Astrantia major rosea greater masterwort M M ? ? ? ? 

S Athanasia acerosa athanasia L ? ? ? ? ? 

P Athyrium filix-femina lady fern M H H H H / 

P Athyrium nipponicum 'Pictum' painted lady fern M M ? ? ? ? 

S Gc Atriplex spp. saltbush VL VL VL VL L VL L 

P Aubrieta deltoidea rock cress L M ? ? ? ? 

S Aucuba japonica Japanese aucuba M M M M / M 

P Aurinia saxatilis hardy alyssum/basket of gold L L M M ? ? 

T Azadirachta indica neem M ? ? ? ? ? 

S Azaliadendron 'Hardjizer's Beauty' Hardijizer's beauty M ? ? ? ? ? 

S T Azara dentata orono M / M ? / / 

S T Azara integrifolia azara M / M ? / / 

S T Azara microphylla box leaf azara M / M M M / 

P Babiana stricta hybrids baboon flower L L L ? / / 

S Baccharis pilularis consanguinea coyote brush L L L L / / 

S Gc Baccharis pilularis cvs. dwarf coyote brush L L L L / / 

S Baccharis sarothroides desert broom VL L VL L L L 

S Gc Baccharis 'Centennial' bentennial baccharis VL L VL L L L 

Bacopa 'Snowflake' (See Sutera spp.) 

S T Baeckea virgata tall baeckia L ? ? ? ? ? 

P Baileya multiradiata desert marigold ? ? ? L L L 

P Ballota pseudodictamnus Grecian horehound VL VL ? ? ? ? 

S Bambusa spp. bamboo (Bambusa) L L M M M M 

P S Banksia ericifolia heath-leafed banksia L ? ? ? ? ? 

T S Banksia integrifolia tree banksia L / M M / M 

T S Banksia praemorsa cut-leaf banksia ? ? ? ? ? 

T S Banksia speciosa showy banksia L / M ? / M 

P Baptista australis false indigo L L ? ? ? ? 

66




S Barleria obtusa barleria ? ? M M / / 

T Bauhinia X blakeana Hong Kong orchid tree M / M M / M 

V Bauhinia corymbosa phanera ? ? M ? / M 

T Bauhinia forficata Brazilian butterfly tree M M M M / / 

T S Bauhinia galpinii red orchid bush L \ M M / / 

Bauhinia punctata (see galpinii) 

T Bauhinia variegata (purpurea) purple orchid tree M / M M / M 

P Baumea rubiginosa baumea ? ? H ? ? ? 

T S Beaucarnea recurvata (See Nolina 

recurvata) 

V Beaumontia grandiflora Easter lily vine M / M H / / 

P Begonia fuchoides rosea fuchsia begonia M M M M / / 

P Begonia grandis hardy begonia M M M M / / 

P Begonia 'Richmondensis' Richmond begonia M M M M / M 

P Begonia semperflorens Wax begonia M M M M / M 

P Bellis perenis English daisy M M M M / / 

S V Berberidopsis corallina coral plant M ? ? ? ? ? 

S GC Berberis spp. barberry L L L L L M 

Gc Berberis X stenophylla 'Irwinii' barberry M M M ? M M 

P Bergenia cordifolia heartleaf bergenia M M M H H H 

P Bergenia crassifolia winter blooming bergenia M M M H H H 

P Berlandiera lyrata chocolate scented daisy ? M ? M M M 

P Beschorneria yuccoides Mexican lily / / M ? ? ? 

T Betula fontinalis (occidentalis) water birch H / H H / / 

T Betula utilis var. jaquemontii white barked Himalayan birch H H / / / / 

T Betula nigra river/red birch H H H H / / 

T Betula occidentalis (See B. fontinalis) 

T Betula pendula European white birch H H H H / / 

T Betula platyphyla japonica Japanese mountain birch H H ? ? ? ? 

P Bidens triplinervia tickseed VL ? ? ? ? ? 

V Bignonia capreolata cross vine M ? ? ? ? ? 

P Billbergia spp. queen's tears etc. M / M M / M 

T Bischofia javanica toog / / M ? / / 

P Blechnum occidentale hammock fern H ? H ? ? ? 

P Blechnum penna-marina alpine water fern ? ? ? ? ? ? 

P Blechnum spicant deer fern L ? M ? ? ? 

P Bletilla striata hyacinth orchid M M M ? ? ? 

P Bolax gummifera (glebaria) bolax/glebaria M ? ? ? ? ? 

S Boronia spp. boronia M / M / / / 

P Bothriochloa barbinoides cane bluestem L ? ? ? ? ? 

S Gc Bougainvillea spp. bougainvillea L L L L / M 

P Bouteloua curtipendula sideoats gramma VL L ? ? ? ? 

P Bouteloua gracilis blue gramma L L ? ? M ? 

T Brachychiton acerifolius flame tree L / L M / / 

T Brachychiton discolor Queensland lace bark M / L M / / 

T Brachychiton X hybridus hybrid brachychiton M / M M / M 

T Brachychiton populneus bottle tree L L L L M M 

T Brachychiton rupestris Queensland bottle tree / / L L / M 

P Brachycome spp. Swan River daisy M M M M M M 

P Brachyglottis greyi (Senecio greyi) groundsel L ? M ? ? ? 

T Brahea armata blue hesper palm L L L L L L 

T Brahea brandegeei San Jose hesper palm L ? M ? ? ? 

T Brahea edulis Guadalupe palm L ? L L L L 

Brassaia actinophylla (See Schefflera 

actinophylla) 

Bravoa geminiflora (See Polyanthes 

geminiflora) 

S Breynia nivosa (distacha) Hawaiian snow bush ? ? H H / / 

P Briza media quaking grass L ? M M M M L 

P Brodiaea spp. brodiaea VL VL L L / / 

67




S Brugmansia spp. angel's trumpet M / M H / / 

S Brunfelsia pauciflora yesterday today and tomorrow M M M H / H 

P Brunnera macrophylla Siberian bugloss H H H ? ? ? 

S Buddleja alternifolia fountain butterfly bush L L M / M M 

S Buddleja davidii butterfly bush L L M M M M 

S Buddleja marrubiifolia woolly butterfly bush ? L ? L / L 

P Bulbine frutescens stalked bulbine L ? L L / L 

P Bulbinella robusta bulbinella L ? ? ? ? ? 

T Bursera hindsiana bursera ? ? / / / M 

T Butia capitata pindo palm L L L L L L 

S Buxus microphylla japonica Japanese boxwood M M M M M M 

S Buxus sempervirens English boxwood M M M / M M 

S Caesalpinea cacalaco cascalote ? ? ? ? / L 

S Caesalpinea gilliesii desert bird of paradise L L L L M M 

S Caesalpinea mexicana Mexican bird of paradise ? / ? L / L 

S Caesalpinea platyloba ? ? ? ? ? ? 

S Caesalpinea pulcherrima dwarf poinciana L L M M / M 

P Calamagrostis spp. feather reed L ? M M ? ? 

P Calamintha spp. calamint M M ? ? ? ? 

P Calceolaria spp. slipper flower/slipperwort M / M ? ? ? 

S Calliandra californica Baja fairy duster / / VL L / L 

S Calliandra emarginata dwarf powderpuff ? ? ? ? ? ? 

S Calliandra eriophylla fairy duster / / VL VL / L 

S Calliandra haematocephala pink powder puff / / M M / H 

S Calliandra tweedii trinidad flame bush / / M M / M 

S Callicarpa bodinieri beauty berry M M ? ? ? ? 

S Callicarpa dichotoma lavender beautyberry M M M ? ? ? 

S Callicarpa japonica beauty berry M M ? M / / 

T S Callistemon citrinus bottle brush L L L L / M 

T S Callistemon pinifolius pine-leafed bottlebrush ? ? L L ? ? 

T S Callistemon salignus pink tips/white bottlebrush L M M ? / ? 

T S Callistemon speciosus Albany bottlebrush ? ? M ? / M 

T S Callistemon subulatus callistemon (subulatus) ? ? L ? ? ? 

T S Callistemon viminalis weeping bottle brush L L M M / M 

S Calluna vulgaris Scotch heather M M / / / / 

T Calocedrus decurrens incense cedar M M M M M / 

S Calocephalus brownii cushion bush L / L L / L 

T Calodendrum capense cape chestnut L / M M / / 

S Calostemma purpureum garland lily M ? ? ? ? ? 

S Calothamnus quadrifidus net bush L ? M ? / ? 

S Calycanthus floridus Carolina allspice M ? ? ? ? ? 

S Calycanthus occidentalis western spice bush L L M M / / 

P Calyophus drummondii calyophus (drummondii) M ? ? ? ? M 

Gc Calyophus hartwegii Sierra sundrop L ? ? ? ? M 

S Camellia japonica camellia M M M H / H 

S Camellia sasanqua sasanqua camellia M M M M / H 

P Camissonia cherianthifolia (Oenothera) beach evening primrose L ? L / / / 

Gc Campanula poscharskyana Serbian bell flower M M M M / M 

P Campanula spp. bell flower M M M M / M 

V Campsis spp. trumpet creeper L L M M M M 

P Canna spp. canna M M M H M M 

S Cantua buxifolia magic flower M / M ? ? ? 

S Capparis spinosa caper bush L / L ? ? ? 

P Carex (garden spp.) sedge M M M M / M 

Gc Carissa macrocarpa (prost.cvs.) Natal plum L / M M / M 

S Carissa spp. Natal plum L / M M / M 

P Carlina acaulis stemless carline thistle ? ? ? ? ? ? 

S Carnegiea gigantea saguaro / / VL L / L 

S Carpenteria californica bush anemone L L L M / / 

T Carpinus betulus 'Fastigiata' European hornbeam M M / / / / 

68




Gc Carpobrotus spp. ice plant (Carpobrotus) L M VL L / L L L 

T Carya illinoensis pecan L M M M M M 

S P Caryopteris X clandonensis blue mist M M M M / / 

S P Caryopteris incana common bluebeard ? ? ? M ? ? 

T Caryota mitis clustered fishtail palm / / M / / / 

T S Caryota urens fishtail wine palm H / M H / / 

T Casimiroa edulis white sapote M / M M / / 

Cassia australis (See Senna australis) 

Cassia artemesioides (See Senna 

artemesioides) 

Cassia bicapsularis (C. candolleana) 

See Senna bicapsularis 

Cassia didymobotria (See Senna 

didymobotria) 

S Cassia eremophila (C.nemophila) desert cassia / ? L L L L 

Cassia goldmanii (See Senna 

polyantha) 

T Cassia leptophylla gold medallion tree L L M M / / 

Cassia lindheimeriana (See Senna 

lindheimeriana) 

Cassia odorata (See Senna odorata) 

Cassia phyllodenia (See Senna 

phyllodenia) 

Cassia spectabilis (C.excelsa) 

Cassia splendida (See Senna 

splendida) 

Cassia sturtii (See Senna sturtii) 

S Cassia tomentosa (See Senna 

multiglandulosa) 

S Cassia wizlizeni shrubby cassia ? ? L ? / L 

T Castanopsis cuspidata copper false chestnut ? ? ? ? ? ? 

T Castanospermum australe Moreton Bay chestnut L / M M / / 

T Casuarina cunninghamiana river she-oak L L L L M M 

Casuarina stricta (See Allocasuarina 

verticilliata) 

T Catalpa bungei umbrella catalpa L ? ? ? ? ? 

T Catalpa speciosa western catalpa L M M M M M 

P Catananche caerulea cupid's dart M L M ? ? ? 

P Catharanthus roseus Madagascar periwinkle M M M M M M 

P Cautleya spicata cautleya H ? ? ? ? ? 

S Gc Ceanothus spp. California lilac VL L VL L L / 

S Gc Ceanothus cultivars ceanothus L L L L L / 

T Cedrus atlantica Atlas cedar M M L M M M 

T Cedrus deodora deodar cedar L M L M M M 

T Cedrus libani cedar of Lebanon M M L M ? ? 

T Celtis australis European hackberry L M / / M M 

T Celtis occidentalis common hackberry L L / M M M 

T Celtis reticulata western hackberry L / / / L L 

T Celtis sinensis Chinese hackberry L M / M M M 

P Centaurea cineraria dusty miller (cineraria) L L M M / M 

P Centaurea dealbata Persian knapweed M ? M ? ? ? 

P Centaurea gymnocarpa velvet centaurea L L M M / M 

P Centaurea montana perennial cornflower L ? ? ? ? ? 

P Centaurea rupestris centaurea (rupestris) ? ? ? ? ? ? 

P Centranthus ruber red valerian VL VL L L / M L 

P Centratherum punctatum porcupine flower ? ? M ? ? ? 

S Cephalocereus spp. old man cactus VL / VL L L L 

Gc Cephalophyllum spp. ice plant (Cephalophyllum) L L L L / L 

Gc Cerastium tomentosum snow in summer M M M M M M 

T Ceratonia siliqua carob L L L L / L 

69




S Ceratostigma abyssinicum African plumbago L / M M M M 

S Ceratostigma griffithii Burmese plumbago L M M M M M 

Gc Ceratostigma plumbaginoides dwarf plumbago L M M M M M 

S Ceratostigma willmottianum Chinese plumbago M M M M ? ? 

T Cercidiphyllum japonicum Katsura tree M M ? ? / / 

T Cercidium floridum (See Parkinsonia 

florida) 

T Cercidium microphyllum little leaf palo verde / VL VL L / L 

T Cercidium praecox Sonoran palo verde / L VL L / L 

T Cercidium 'Sonorae' Sonora cercidium ? ? ? ? / L 

T Cercis canadensis eastern redbud M M M M / / 

S Cercis chinensis Chinese redbud M M ? ? ? ? 

T S Cercis mexicana Mexican redbud L L ? ? ? ? 

T S Cercis occidentalis western redbud VL VL L L / / 

T Cercis reniformis southwest redbud L L ? ? ? ? 

T S Cercis siliquastrum Judas tree M M ? ? ? 

S Cercocarpus betuloides mountain ironwood VL VL VL VL VL / 

S Cercocarpus minutiflorus San Diego mountain mahogany L ? VL VL / / 

S Cereus peruvianus Peruvian apple cactus / ? L L / L 

S V Cestrum auranticum orange cestrum M / M M ? ? 

S Cestrum elegans red cestrum M / M M / M 

S Cestrum fasciculatum var. 'Newellii Newell cestrum M ? M ? ? ? 

S Cestrum nocturnum night jessamine M M M M / M 

S Chaenomeles cvs. flowering quince L L M M L M 

P Chaenorhinium glareosum dwarf snapdragon M ? ? ? ? ? 

T S Chamaecyparis spp. false cypress M M / / / / 

S P Chamaedorea spp. chamaedorea / / H H / H 

Gc P Chamaemelum nobile chamomile L M M M M M 

T S Chamaerops humilis Mediterranean fan palm L L M M M M 

S Chamelaucium uncinatum Geraldton wax flower L L L M / M 

P Chasmanthe aethiopica chasmanthe L ? L L ? ? 

P Chasmanthium latifolium sea oats L M M M M M 

P Cheilanthes lanosa hairy lip fern M ? ? ? ? ? 

P Cheiranthus cheiri (See Erysimum 

cheiri) 

T Chilopsis linearis desert willow VL VL VL L M M 

S Chimonanthus praecox wintersweet ? ? M ? ? ? 

S Chimonobambusa marmorea 

marbled bamboo L L M M / M 

(Arundinarea) 

T Chimonobambusa quadrangularis square-stemmed bamboo L L M M / M 

T Chionanthus retusus Chinese fringe tree M M M M / / 

T Chionanthus virginicus white fringe tree M / ? ? ? ? 

T X Chitalpa tashkentensis chitalpa L M L L L M 

S Choisya ternata Mexican orange M M M M / M 

P Chondropetalum tectorum cape reed H ? M ? ? ? 

T Chorisia insignis white floss silk tree M / M L / M 

T Chorisia speciosa floss silk tree L / L L / M 

S Chorizema cordata flame pea M ? ? ? ? ? 

Chrysanthemum frutescens (See 

Argyranthemum frutescens) 

Chrysanthemum maximum (See 

Leucanthemum X superbum) 

Chrysanthemum parthenium (See 

Tanacetum parthenium) 

P Chrysopsis villosa (See Heterotheca 

villosa) 

S Chrysothamnus nauseosus albicaulis rabbit brush / / ? ? VL ? 

P Chusquea coronalis bamboo H ? M H ? ? 

P Cibotium glaucum Hawaiian tree fern / / H H / / 

T Cinnamomum camphora camphor tree M / M M / M 

V Cissus antarctica kangaroo treebine L M M M / M 

70




V Cissus rhombifolia grape ivy M / M M / M 

V Cissus trifoliata treebine ? / ? ? ? L 

S Gc Cistus spp. rockrose L L L L L L L 

T S Citrus spp. orange, lemon etc. M M M M / M 

V Clematis armandii evergreen clematis M M M M M M 

V Clematis hybrids and cvs deciduous clematis M M H H M M 

S Clematis integrifolia bushy clematis M M ? ? ? ? 

V Clematis lasiantha pipestem clematis L L VL L / / 

V Clematis ligusticifolia western virgin's bower M ? ? L / / 

V Clematis pauciflora small flowered clematis ? ? VL L ? ? 

S Cleome isomeris bladder pod VL VL VL VL L L 

P Clerodendrum bungei cashmere bouquet L M M ? ? ? 

T S Clerodendrum trichotomun harlequin glory bower M ? ? ? ? ? 

S Clerodendrum ugandense butterfly bush M ? M M / M 

T S Clethra alnifolia summersweet M / ? ? ? ? 

S Cleyera japonica sakaki M M M ? ? ? 

S Clianthus puniceus parrot's beak L L M M ? ? 

P Clivia miniata Kaffir lily M M L M / M 

V Clytostoma callistigioides violet trumpet vine M M M M / M 

S Cneoridium dumosum bushrue ? ? ? ? L L 

V Cobaea scandens cup and saucer vine M M ? ? ? ? 

T S Cocculus laurifolius laurel leaf cocculus M M M M / M 

P Colchicum agrippium autumn crocus VL VL M M M M 

S Coleonema album white breath of heaven M M M M / / 

S Coleonema pulchrum breath of heaven M M M M / / 

S T Comarostaphylis diversifolia (See 

Archtostaphylos diversifolia) 

V Combretum fruticosum combretum / / M M / / 

S Convolvulus cneorum bush morning glory L L L L L L 

Convolvulus mauritanicus (see C. 

Sasbatius) 

Gc P Convolvulus sabatius ground morning glory L L L L M M 

S Gc Coprosma X kirkii creeping coprosma L L M M / / 

Coprosma pumila (See C.petriei) / 

S Gc Coprosma petriei 'Verde vista' verde vista coprosma L L M M / / 

S Coprosma repens mirror plant M M M M / / L 

T S Cordia boissieri Texas olive ? ? ? L L L 

S Cordia parvifolia little leaf cordia ? ? L L / L 

T Cordyline australis New Zealand cabbage tree L M L M M M L 

T S Cordyline indivisa blue dracaena palm L L ? ? ? ? 

S Cordyline stricta palm lily / M M M / M 

S Cordyline terminalis ti plant M / M / / / 

P Coreopsis auriculata'Nana' dwarf coreopsis L L L L M M 

P Coreopsis gigantea giant coreopsis ? ? VL L / / 

P Coreopsis lanceolata coreopsis L L L L M M 

P Coreopsis maritima sea dahlia L ? VL ? ? ? 

P Coreopsis verticilata cvs. threadleaf coreopsis L L L L M M 

P Corethrogyne californica black bush ? ? / / VL / 

T Cornus alba red-barked dogwood M M ? ? / / 

Gc Cornus canadensis bunchberry M M ? ? / / 

T Cornus capitata evergreen dogwood M M M ? / / 

T Cornus 'Eddie's White Wonder' Eddie's white wonder dogwood M M ? ? / / 

T Cornus kousa Japanese dogwood M M / / / / 

T Cornus kousa chinensis Chinese dogwood M M / / / / 

T Cornus florida eastern dogwood M M H H / / 

T Cornus nuttallii western dogwood M M / M / / 

Cornus sericea (See C. stolonifera) 

S Cornus stolonifera red osier dogwood H H / H / / 

S Corokia cotoneaster wire-netting bush M M M M M M 

S Corokia X virgata corokia M ? M ? ? ? 

S Correa spp. Australian fuchsia L L L L / M 

71




S Cortaderia sellowana cvs. pampas grass VL L L L L L L L 

S T Corylopsis spicata winter hazel M ? ? ? / / 

S Corylus avelleana contorta Harry Lauder's walking stick M M / / / / 

S Corylus cornuta californica western hazelnut L ? / / / / 

T S Corylus maxima filbert L / / / / / 

T Corynocarpus laevigata New Zealand laurel M / H / / / 

P Cosmos atrosanguineus chocolate cosmos M M M ? ? ? 

T S Cotinus coggygria smoke tree L L L L L / 

T S Cotinus obvatus American smoke tree L ? ? ? ? ? 

S Cotoneaster spp. (shrubs) cotoneaster L L L M M M L L 

Gc Cotoneaster spp.(ground covers) cotoneaster M M M M M M 

P Cotula lineariloba silver button plant H H M ? ? ? 

P Cotula 'Silver Mound' cotula H H ? ? ? ? 

S P Cotyledon spp. cotyledon L L L L / L 

S Coursetia axillaris baby bonnets ? ? ? ? ? L 

S Cowania mexicana cliff rose L / / L L L 

S P Crassula spp. crassula L L L L / L 

P Craspedia globosa drumsticks M M M M ? ? 

T Crataegus spp. hawthorn M M / M M / L 

T Crinodendron hookerianum lantern tree ? ? ? ? ? ? 

T Crinodendron patagua lily-of-the-valley tree M / M M / / 

P Crinum spp. crinum lily, spider lily M M M M ? M 

P Crocrosmia hybrids (Tritonia) montbrieta L L L L / L 

S Crotalaria agatiflora canary-bird bush L / M M / H 

T S Cryptomeria japonica Japanese cryptomeria M H H H / / 

T Cupaniopsis anacardioides carrotwood M / M M / / 

P Cuphea hyssophyla false heather M M M M / / 

P Cuphea ignea cigar plant M M M M / / 

P Gc Cuphea llavea bat-faced cuphea M ? ? ? / / 

S P Cuphea micropetela cuphea (micropetala) ? ? M ? / / 

T X Cupressocyparis leylandii Leyland cypress M M M / M M 

T Cupressus arizonica ssp. arizonica Cuayamaca cypress VL VL VL L L L 

T Cupressus arizonica var.glabra smooth Arizona cypress VL VL VL L L L 

T Cupressus goveniana Gowen cypress ? ? ? ? ? ? 

T Cupressus guadalupensis forbesii tecate cypress L L VL VL / / 

T Cupressus macrocarpa Monterey cypress M M M / / / L 

T Cupressus sempervirens Italian cypress L M L L M M 

T Cussonia paniculata little cabbage tree / / M ? / 

S P Cyathea cooperii Australian tree fern H H H H / / 

S Cycas revoluta sago palm M M M M M M 

P Cyclamen hederifolium cyclamen L L M ? / M 

P Cyclamen persicum hybrids florists' cyclamen M M M M / M 

Gc P Cymbalaria muralis Kenilworth ivy M M H H / / 

P Cyperus albostriatus dwarf umbrella plant 

P Cyperis spp. umbrella sedge/papyrus H H H H H H 

P Cyrtanthus brachyscyphus dobo lily M ? ? ? ? ? 

P Cyrtanthus purpureus fire lily M ? ? ? ? ? 

P Cyrtomium falcatum holly fern M M H M / M 

Gc Cytisus X kewensis Kew broom M M / / M / 

S Cytisus spp. broom (Cytisus) L L / M / / L L 

S Daboecia cantabrica Irish heath M ? ? ? / / 

S Dahlia imperialis tree dahlia M M M M / ? 

P Dahlia spp. dahlia M M M H H H 

T Dalbergia sissoo sissoo / / / / / M 

S Dalea bicolor dalea (bicolor) / / L L / M 

Gc Dalea capitata dalea (capitata) / / ? ? M M 

S Dalea dorychnioides dalea (dorychnioides) ? ? ? ? ? ? 

S Dalea frutescens black dalea / / M / M M 

P Dalea gattingeri (Petalostemum purple prairie clover ? ? ? ? ? ? 

purpureum) 

Gc Dalea greggii trailing indigo bush ? / L L L L 

72




S Dalea lutea dalea (lutea) / / / ? M M 

Gc Dalea orcutii Baja indigo bush / / L L / L 

S Dalea pulchra indigo/pea bush / / M / M M 

T Dalea spinosa (See Psorothamnus 

spinosa) 

S Dalea versicolor dalea (versicolor) / / M / M M 

P Dalechampia dioscorifolia purple wings ? ? M ? ? ? 

S Gc Dampiera diversifolia dampiera L / M ? ? ? 

P Dampiera trigona dampiera L / M ? ? ? 

S Daphne X burkwoodii Burkwood daphne M M ? ? ? ? 

S Daphne caucasica daphne (caucasia) M ? M ? ? ? 

S Daphne odora winter daphne M M M M / / 

P Darmera peltata umbrella plant/Indian rhubarb H ? ? ? ? ? 

S Dasylirion spp. desert spoon VL / L L L L 

P Davallia trichomanoides squirrel's foot fern L M M H / H 

Gc Delosperma spp. ice plant (Delosperma) L M L L / L L 

P Delphinium spp. delphinium M M M M M M 

T S Dendriopoterium menendezii dendriopoterium ? ? M ? / ? 

S Dendromecon spp. bush poppy VL L VL L / / 

P Deschampsia caespitosa tufted hairgrass L L L L / / 

S Deutzia spp. bridal wreath M M / M M / 

P Dianella intermedia Turutu M ? M ? ? ? 

P Dianella tasmanica blueberry M ? M M / ? 

P Dianthus spp. pink/carnation M M M M M M 

P Diascia spp. twinspur M M M M / / 

P Dicentra spp. bleeding heart M M M H / / 

P Dichelostemma capitatum wild hyacinth L L M ? ? ? 

Gc Dichondra argenta silver dichondra ? ? M ? ? ? 

Gc Dichondra micrantha dichondra M M M H / H 

P Dichorisandra thyrsifolia blue ginger / / H ? / ? 

P Dichroa febrifuga evergreen hydrangea ? ? M ? ? ? 

S P Dicksonia antarctica Tasmanian tree fern H H H H / / 

P Dicliptera suberecta velvet honeysuckle L ? M ? ? M 

P Dictamnus spp. burning bush/dittany L L ? ? ? ? 

P Dierama spp. fairy wand M M M ? ? ? 

P Dietes bicolor fortnight lily L L M M / M 

P Dietes iridioides fortnight lily L L M M / M 

P Dietes vegeta (See D. iridioides) 

P Digitalis lutea hardy/straw foxglove M M ? ? ? ? 

P Digitalis X mertonensis foxglove M M M M M M 

S Dioon spp. Mexican cycad / / M M M M 

T Diospyros kaki Japanese persimmon L M M M M M 

Diplacus (see Mimulus) 

V Dipogon lignosus Australian pea H ? ? ? ? ? 

V Distictis buccinatoria blood red trumpet vine M M M M / M 

V Distictis 'Rivers' royal trumpet vine M M M M / M 

Disygotheca elegantissima (see 

Schlefflera elegantissima) 

Gc Dodonaea procumbens hopseed bush (procumbens) L L L ? ? ? 

S Dodonaea viscosa hopseed bush L L L M / M 

S Dodonaea viscosa 'Purpurea' purple hopseed bush L L L M / M 

V Dolichos labab see Labab purpureus 

T S Dombeya spp. dombeya / / M M / / 

T Dombeya cacuminum strawberry snowball / / M M / / 

P Doronicum orientale (D. caucasium) leopard's bane M ? M ? ? ? 

S Doryanthes palmeri spear lily L / L L / / 

S Dorycnium hirsutum hairy canary clover / ? L ? ? ? 

T Dracaena draco dragon tree L / VL L / / 

S Drepanostachyum falcatum 

blue bamboo L L M M / M 

(Arundinaria) 

S Drepanostachyum hookerianum bamboo L L M M / M 

73




T Drimys lanceolata pepper tree M ? ? ? ? ? 

T Drimys winteri winter's bark M ? ? ? ? ? 

Gc Drosanthemum spp. ice plant (Drosanthemum) L L L L / L 

P Dryopteris arguta sheild/wood fern M ? M ? ? ? 

P Dryopteris dilatata broad buckler fern M ? M ? ? ? 

P Dryopteris erythrosora wood fern M M M M / / 

P Dryopteris felix-mas male fern M ? ? ? ? ? 

Gc Duchesnea indica Indian mock strawberry M M M M / M L 

P Dudleya spp. dudleya, live forever L L VL L L L 

S Duranta erecta (D. repens) sky flower / / M M / M 

S Duranta stenostachya Brazilian sky flower / / M M / / 

P Dyckia spp. dyckia L ? L L ? ? 

P Gc Dymondia margaretae dymondia L L L L / / 

Dyssodia acerosa shrubby dogweed ? ? ? ? ? L 

P Dyssodia pentachaeta golden fleece ? M ? ? M M 

S P Echeveria spp. hens and chickens L L L L / M 

P Echinacea spp. cone flower M M M M M M 

S Echinocactus spp. barrel cactus VL VL L L / L 

Note: Many Echinocactus spp. are now 

in other genera including Ferrocactus, 

Echinopsis, Parodia, Sclerocactus and 

others 

P Echinops exaltus globe thistle M M M ? ? M 

P Echinopsis spp. (Trichocereus spp.) torch cactus L L L L L L 

S P Echium candicans (fastuosum) pride of Madeira L L L L / M L 

S P Echium pininana pride of Teneriffe L L ? ? ? ? 

Bi Echium 'Purple Tower' purple tower echium L L ? ? ? ? 

Bi Echium wildpretii tower of jewels L L M M / / 

S Edraianthus graminifolius grassy bells L L ? ? ? ? 

T S Elaeagnus angustifolia Russian olive L L L L M M L 

S Eleagnus X ebbengei Ebbinge's silverberry L L ? ? M M 

S Elaeagnus pungens silverberry L L L L L L 

T Elaeocarpus decipiens Japanese blueberry tree M ? M ? ? ? 

P Elymus spp. (also see Leymus spp.) wild rye L L L L M M 

P Encelia californica California encelia / / VL L / L 

S Encelia farinosa brittle bush / / VL L L L 

S Enkianthus campanulatus red-veined enkianthus M H ? ? ? / 

S P Ensete ventricosum Abyssinian banana H H H H / H 

S Epacris gunii Australian heath M ? ? ? ? ? 

P Epidendrum reed stem hybrids epidendrum M / M M ? ? 

P Epilobium spp.(Zauchneria) California fuchsia L L VL L M M 

Gc Epimedium grandiflorum bishop's hat M M / / / / 

P Equisetum spp. horsetail H H H H H H 

S Eremophila glabra emu bush L L L ? / L 

S Eremophila maculata spotted emu bush L L L L / L 

S Eremophila racemosa Easter egg bush ? ? L L ? ? 

P Erianthus ravennae plume grass ? ? ? ? ? ? 

S Gc Erica spp. heath M M M / / / L 

S Ericameria laricifolia (Haplopappus) turpentine bush / / / / L L 

P Erigeron divergens native fleabane ? ? ? ? ? ? 

P Erigeron formosissimus fleabane M ? ? ? ? ? 

P Erigeron glaucus beach aster L / M M / / 

P Erigeron karvinskianus fleabane L M M M M M 

P Erigeron speciosus Oregon fleabane ? ? ? ? ? ? 

S P Eriogonum spp. buckwheat L L VL L L L 

P Eriophyllum confertiflorum golden yarrow L ? VL VL / / 

P Eriophyllum lanatum chalk buckwheat L ? ? ? ? ? 

Erodium chaemedryoides (See E. 

reichardii) 

P Gc Erodium chrysanthum cranessbill (chrysanthum) L M M M M M 

P Erodium corsicum heron's-bill ? ? ? ? ? ? 

74




P Erodium reichardii alpine geranium L M M M M M 

P Eryngium pandanifolium sea holly M ? ? ? ? ? 

P Eryngium variifolium sea holly M ? ? ? ? ? 

T Eryobotrya deflexa bronze loquat M M M M / M 

T Eryobotrya japonica loquat L L M M / M 

P Erysimum 'Bowles Mauve' Bowles mauve wallflower L L M M ? ? 

P Erysimum cheiri (Cherianthus cheiri) wallflower M M M M M M 

P Erysimum helveticum wallflower M ? ? ? ? ? 

P Erysimum hyeraciifolium Siberian wallflower L L L ? ? ? 

P Erysimum 'Jubilee' jubilee wallflower L L L ? ? ? 

P Erysimum linifolium wallflower L L L M / M 

P Erysimum menziesii wallflower L L L ? ? ? 

P Erysimum pulchellum wallflower L L L ? ? ? 

P Erysimum suffrutescens (concinnum) Pt. Reyes wallflower L L ? ? ? ? 

P Erysimum 'Wenlock Beauty' Wenlock beauty wallflower ? ? L ? ? ? 

T Erythrina americana(E.coralloides) naked coral tree / / L L / / 

T Erythryna X bidwillii coral tree L L L L / / 

T Erythrina caffra Kaffir bloom coral tree / / L L / / 

T S Erythrina crista-galli cockspur coral tree M M L L / M 

T Erythrina falcata coral tree (falcata) / / L / / / 

T Erythrina humeana Natal coral tree / M L M / / 

T Erythrina X sykesii Sykes coral tree / / L L / / 

S Escallonia spp. escallonia M M M M / M 

P Eschscholzia californica California poppy VL VL L L L L 

S Espostoa lantana Peruvian old man cactus ? ? L L L L 

T Eucalyptus camaldulensis red gum L L L L M M L 

T Eucalyptus campaspe silver gimlet ? L M ? / M 

T Eucalyptus cinerea ash leaved gum, silver dollar tree VL L L M ? ? 

T Eucalyptus citriodora lemon scented gum L / L M / M 

T Eucalyptus cladocalyx sugar gum L / L L / / 

T Eucalyptus deglupta mindinao gum / / M M / / 

T Eucalyptus erythrocorys red cap gum L L M M / M 

T Eucalyptus ficifolia red flowering gum L / M M / / 

T Eucalyptus formanii Forman's mallee ? ? L ? ? L 

T Eucalyptus globulus blue gum L L L M / / L L 

Eucalyptus grandis flooded/rose gum M M M M / / 

T Eucalyptus gunnii cider gum L L L L ? ? 

T Eucalyptus kruseana book-leaf mallee VL / L ? / ? 

T Eucalyptus largiflorens black box ? ? ? ? ? ? 

T Eucalyptus lehmannii bushy yate L L L L / / 

T Eucalyptus leucoxylon white ironbark L L L L / M 

T Eucalyptus loxophleba York gum ? VL ? VL / / 

T Eucalyptus macranda long flowered marlock VL VL VL L / L 

T Eucalyptus maculata spotted gum L / M M / / 

T Eucalyptus microtheca coolibah L L L L M M 

T Eucalyptus nicholii Nichol's willow leaf peppermint L L M M M M 

T Eucalyptus polyanthemos silver dollar gum L L L L M M 

T Eucalyptus preissiana bell mallee VL / L ? / ? 

T Eucalyptus pulverulenta silver mountain gum L M M M / M L 

T Eucalyptus robusta swamp mahogany L L L L / / 

T Eucalyptus rudis flooded gum L L L L M M 

T Eucalyptus sargentii Salt River mallet ? VL ? L / L 

T Eucalyptus sideroxylon red iron bark L L L L M M 

T Eucalyptus spathulata swamp mallee L / L L / M 

T Eucalyptus torelliana cadaga / / ? ? ? ? 

T Eucalyptus torquata coral gum L L L M / M 

T Eucalyptus viminalis manna gum L L L M / M 

T Eucalyptus woodwardii lemon flowered gum VL ? L ? ? L 

P Eucomis bicolor hybrids pineapple lily M ? ? ? ? ? 

T Eucryphia glutinosa hardy eucryphia M ? ? ? ? ? 

75




T Eucryphia x intermedia eucryphia M M ? ? ? ? 

T Eucryphia lucida (billardieri) leatherwood M M ? ? ? ? 

S Euonymous alatus burning bush M M ? ? ? ? 

Gc Euonymus fortunei purple winter creeper M M M M M / 

V Euonymus fortunei radicans winter creeper M M / M M M 

S Euonymus japonicus evergreen euonymus L L M M M M 

S Euonymus kiautschovicus euonymus L ? ? ? ? ? 

P Eupatorium spp. mistflower M ? M ? M M 

P Euphorbia characias euphorbia L L L L ? ? 

T S Euphorbia cotinifolia Carribean copper plant / / M / / / 

P Euphorbia cyparissias cypress spurge L ? ? ? ? ? 

P Euphorbia dulsis euphorbia (dulsis) M ? ? ? ? ? 

S Euphorbia lambii tree euphorbia ? ? ? ? ? ? 

S Euphorbia milii crown of thorns / L L L / L 

P Euphorbia myrsinites euphorbia L ? L L ? ? 

P Euphorbia polychroma (epithymoides) cushion spurge L L ? ? ? ? 

S Euphorbia pulcherrima poinsettia / / L M / M 

S Euphorbia rigida euphorbia / L VL L / L 

P Euphorbia segueriana niciciana euphorbia ? ? ? ? ? ? 

S Euphorbia tirucalli milk bush / / VL / / L 

S P Euryops pectinatus euryops/shrub daisy L L L L M M 

S P Euryops pectinatus viridis green euryops M M M M M M 

P Evolvulus pilosus (nuttallianus) evolvulus ? ? M M / ? 

S Fabiana imbricana pichi ? ? M ? ? ? 

T Fagus sylvatica European beech M H / / / / 

P Fallopia japonica Japanese knotweed ? ? ? ? ? ? 

S Fallugia paradoxa Apache plume / ? VL VL L L 

P Farfugium japonicum (Ligularia) farfugium/ligularia H H H ? ? ? 

Fargesia murielae 

see Thamnocalamus spathaceus 

S P Fargesia nitida (See Sinarundinaria 

nitida) 

P Fascicularia pitcairnifolia fascicularia ? ? L ? ? ? 

V X Fatshedera lizei tree ivy M M M H / H 

S Fatsia japonica Japanese aralia M M M M / H 

Feijoa sellowiana (See Acca sellowiana) 

S Felicia amelloides blue marguerite M M M M / M 

S Felicia fruticosa shrub aster L L L M / M 

S Ferocactus spp. barrel cactus VL VL VL L L L 

P Festuca californica California fescue L M M M M M 

P Festuca cinerea fescue (cinerea) L ? M ? ? ? 

P Festuca idahoensis Idaho fescue VL L ? ? ? ? 

P Festuca muelleri Mueller's fescue ? ? M M ? ? 

P Festuca glauca blue fescue L L M M M M 

P Gc Festuca rubra creeping red fescue L / H H / / 

P Festuca tenuifolia fescue (tenuifolia) M ? ? ? ? ? 

T Ficus auriculata Roxburgh fig / / M M / / 

T Ficus barteri banana-leaf fig ? ? ? ? ? ? 

T S Ficus benjamina weeping Chinese banyan / / M / / M 

T Ficus carica edible fig M M M M M M L 

T S Ficus elastica rubber plant / / M M / / 

T Ficus florida Florida fig / / M M / / 

T Ficus macrophylla Moreton Bay fig / / M M / / 

T Ficus microcarpa Indian laurel fig/ laurel fig M / M M / M 

T Ficus microcarpa 'Green Gem" green gem ficus M / L M / M 

T Ficus microphylla (See Ficus rubiginosa) 

V Ficus pumila creeping fig M M M M M M 

T Ficus retusa nitida (See Ficus 

microcarpa) 

76




T Ficus rubiginosa rusty leaf fig M / M M / / 

Filipendula hexapetela 

see Filipendula vulgaris 

P Filipendula vulgaris Meadowsweet H ? ? ? ? ? 

S Forestiera neomexicana desert olive ? ? L L L L 

S Forsythia X intermedia forsythia L L M M M M 

S Fothergilla gardenii dwarf fothergilla M M ? ? ? ? 

S Fouquieria splendens ocotillo / / VL L L L 

Gc Fragaria spp. strawberry M M M M M M 

P Francoa ramosa bridal wreath M M M M / / 

P Francoa sonchifolia bridal wreath M ? M ? / / 

T S Franklinia alatamaha (Gordonia franklin tree M / / / / / 

altmahama) franklin tree 

T Fraxinus americana white ash M M / / / / 

T Fraxinus griffithi Griffith ash ? ? ? ? ? ? 

T Fraxinus latifolia Oregon ash M M / / / / 

T Fraxinus 'Moraine' moraine ash M M / / M M 

T Fraxinus oxycarpa 'Raywood' raywood ash M M M M M / 

T Fraxinus pennsylvanica'Marshal' green ash M M / / M / 

T Fraxinus uhdei evergreen ash M M M M H H 

T Fraxinus velutina Arizona ash M M M M M M 

T Fraxinus velutina 'Modesto' Modesto ash M M M M M M 

S Fremontodendron spp. flannel bush VL VL VL L / / 

P Fuchsia spp. fuchsia M M H H / / 

S Furcraea spp. furcraea L / / L L ? 

P Gaillardia grandiflora blanket flower L L M M M M 

P Galium odoratum sweet woodruff M M H / / / 

P Galtonia candicans summer hyacinth ? ? ? ? ? ? 

S Galvesia juncea Baja bush-snapdragon / / VL L / M 

S Galvesia speciosa island bush snapdragon L L VL L ? M 

S Gamolepis chrysanthemumoides gamolepis M M M M / H 

S Gardenia spp. gardenia M M M M / M 

S Garrya eliptica coast silktassel L L L M / / 

S Garrya flavescens ashy silktassel / ? L L / / 

S Garrya fremontii Fremont silktassel L L VL / / / 

P Gasteria spp. mother-in-law's tongue etc. L L L L / ? 

S Gaultheria mucronata (Pernettya prickly heath M ? ? ? ? ? 

mucronata) 

Gc Gaultheria procumbens creeping wintergreen M M / / / / 

S Gaultheria shallon salal M M / H / / 

P Gaura lindheimeri gaura M M M M M M 

Gc Gazania spp. gazania M M M M M M 

T Geijera parviflora Australian willow M M L M M M 

V Gelsemium rankinii swamp jessamine ? ? ? ? ? ? 

V Gelsemium sempervirens Carolina jessamine L L M M / M 

Gc Genista lydia Lydia woadwaxen M ? M ? / / 

Gc Genista pilosa (Vancouver Gold) Vancouver gold genista M M / M ? M 

S Genista spp. broom (Genista) L L M M / M L L 

P Gentiana scabra procumbens gentian H ? ? ? ? ? 

P Geranium spp. cranesbill M M M M M M 

P Gerbera jamesonii Transvaal daisy M M M M / M 

P Geum spp. avens M M M M M / 

T Ginkgo biloba maiden hair tree M M M M M ? 

P Gladiolus spp. gladiolus L L L L / / 

P Gladiolus hybrids & selections gladiolus M M M M / / 

P Gc Glechoma hederaceae ground ivy L M M H / / 

T Gleditsia triacanthos honey locust L L M L L L 

P Globularia cordifolia creeping globe daisy L ? ? ? ? ? 

P Globularia X indubia globe daisy M ? ? ? ? ? 

P Goniolimon incanum (Limonium 

speciosum) 

statice L L L M / M 

77




P Goniolimon tataricum (Limonum Tartarian statice L ? M ? ? ? 

tataricum) 

T Gordonia axillaris gordonia H ? ? ? ? ? 

T Gordonia lasianthus lob lolly bay M ? H ? ? ? 

S Graptopetalum spp. graptopetalum VL L L L / M 

S Grevillea spp. grevillea L L L L / M 

T Grevillea robusta silk oak L L L M / M 

S Grewia occidentalis lavender star flower M M M M / M 

P Grindelia camporum gum plant ? ? L ? ? ? 

S Griselinia littoralis kapuka M / M / / / 

S Griselinia lucida puka M / M / / / 

P Gunnera magellanica gunnera H / H H / / 

S Gutierrezia sarothrae snakeweed ? ? / / L L 

P Gypsophila cerastioides baby's breath ? L M M / / 

P Gypsophila paniculata baby's breath L L M M / M 

P Gypsophila repens creeping baby's breath M M M M / / 

Habranthus andersonii (See H. 

/ 

tubispanthus) 

P Habranthus robustus (Zephranthes) pampas lily M M M M / M 

Habranthus texanus (See H. 

tubispanthus) 

P Habranthus tubispathus habranthus M M M M / / 

S Hakea laurina sea urchin tree L L L L / / 

S Hakea suaveolens sweet hakea L L L L / / 

P Hakonechloa macra hakone grass M M ? ? ? ? 

S X Halmiocistus B866sahucci halmiocistus L ? L L ? ? 

S X Halmiocistus wintonensis halmiocistus L ? L L ? ? 

S Halimium lasianthum sun rose L L L ? ? ? 

S Hamamelis virginiana common witch hazel M M / / / / 

S Hamelia patens Texas firecracker bush ? ? ? ? / M 

V S Hardenbergia comptoniana western Australia coral pea M M M M / M 

V S Hardenbergia violacea lilac vine M M M M / M 

T Harpephyllum caffrum Kaffir plum M / M M / / 

T Harpullia arborea tulipwood / / M / / / 

P Haworthia spp. haworthia L L L L / L 

S Hebe spp. hebe M M M M / / 

GC V Hedera canariensis Algerian ivy M M M M M M L 

GC V Hedera helix English ivy M M M M M M L L 

Gc V Hedera nepalensis Himalayan ivy M ? ? ? ? ? 

P Hedychium coccinium red ginger lily / / H H / H 

P Hedychium coronarium white ginger lily M / H H / H 

P Hedychium flavescens yellow ginger L ? H H / H 

P Hedychium garnerianum Kahili ginger M / H H / H 

P Hedychium greenei red ginger / / H H / H 

P Helenium bigelovii Bigelow sneezeweed L L ? ? ? ? 

P Helenium hoopesii orange sneezeweed L L ? ? ? ? 

S Helianthemum appenium white rock rose ? ? ? ? ? ? 

P Helianthemum nummularium helianthemum L L L L / / 

P Helianthus angustifolius swamp sunflower H ? ? ? ? ? 

P Helianthus maximiliani Maximilian sunflower M L ? ? ? ? 

P Helichrysum bracteatum straw flower ? L M M ? ? 

P Helichrysum petiolare licorice plant ? M M M ? ? L 

S Helichrysum rosemarinifolium ( See 

Ozothamnus roasemarinifolius) 

P Helictotrichon sempervirens blue oat grass L L M M M M 

P Heliopsis helianthoides scabra golden sunflower H ? ? ? ? ? 

P Heliotropum arborescens common heliotrope M M M M ? M 

P Helleborus spp. Christmas/Lenten rose M M M M / / 

P Hemerocallis spp. day lily M M M M M M 

Gc Herniaria glabra green carpet H M M M / / 

S Hesperaloe funifera Coahuilan hesperaloe / / VL L L L 

78




S Hesperaloe parviflora red/ yellow yucca / / VL L L L 

S Hesperantha spp. hesperantha L ? ? L ? ? 

S Heterocentron elegans Spanish shawl / / ? ? ? ? 

S Heteromeles arbutifolia toyon VL VL L L / / 

P Heterotheca villosa (chrysopsis villosa) hairy golden aster L ? ? ? ? ? 

P Heuchera maxima island alum root M / M M / / 

P Heuchera micrantha alum root M M M M M M 

P Heuchera sanguinea coral bells M M M M M M 

P X Heucherella tiarelloides 'Bridget Bridget bloom heucherella H H M ? ? ? 

Bloom' 

P Hibanobambusa tranquillans inyouchikuzoku H ? ? ? ? ? 

S Hibbertia aspera hibbertia (aspera) M / ? ? ? ? 

S Hibbertia cuniformis cut leaf Guinea flower M M M ? / M 

S Gc Hibbertia pedunculata hibbertia (pedunculata) M / ? ? M 

V Hibbertia scandens Guinea gold vine M M M M / M 

S Hibbertia vestita hibbertia (vestita) M / ? ? ? ? 

P Hibiscus moscheutos mallow rose M M M ? ? ? 

S Hibiscus mutabilis confederate rose M M ? M ? ? 

S Hibiscus rosa-sinensis Chinese hibiscus M M M M / H 

S Hibiscus syriacus rose of Sharon L M M M M M 

P Hibiscus trionum flower-of-an-hour M ? ? ? ? ? 

P Hippeastrum spp. amaryllis M M M M ? ? 

P Hippolytia herderi (Tanacetum herderi) hippolytia ? ? ? ? ? ? 

S Holodiscus discolor sea foam L ? M M / / 

P Homeria spp. cape tulip ? ? M M ? ? 

Homoglossum watsonium (See 

Gladiolus spp.) 

P Hosta spp. plantain lily M M / / / / 

P Houttuynia cordata 'Chameleon' chameleon houttuynia M M M ? ? ? 

S Howea forsterana Kentia palm / / M M / / 

P Hunnemannia fumarifolia Mexican tulip poppy L L M M ? ? 

S V Hydrangea anomala petiolaris climbing hydrangea M H / H / / 

S Hydrangea arborescens snowball hydrangea M H ? ? ? ? 

S Hydrangea aspera villosa lacecap hydrangea M H ? ? ? ? 

S Hydrangea macrophylla hydrangea M H M H H H 

S Hydrangea paniculata 'Grandiflora' peegee hydrangea M ? M ? ? ? 

S Hydrangea quercifolia oakleaf hydrangea M ? M M H H 

S Hydrangea serrata blue bird hydrangea H ? ? ? ? ? 

S Hymenoclea monogyra cheese bush ? ? ? ? VL VL 

T Hymenosporum flavum sweet shade M / M M / / 

Hymenoxys acaulis (See Tetraneuris 

acaulis) 

S Hypericum beanii Henry St. John's wort M M M M M / 

Gc Hypericum calycinum Aaron's beard M M M M M / 

S Gc Hypericum empetrifolium nanum hypericim (e nanum) M ? ? ? ? / 

S P Hypericum frondosum hypericum ( frondosum) M ? ? ? ? / 

S Hypericum 'Hidecote' St.Johnswort M M M M M / 

S Hypericum X inodorum 'Albury Purple' Albury purple hypericum M ? ? ? ? / 

P Hypericum kelleri Keller hypericum M ? ? ? ? / 

S P Hypericum X moseranum gold flower M M M M M / 

S Hypericum olympicum olympic hypericum L ? ? ? ? / 

S Hypericum 'Rowallane' Rowall hypericum M ? ? ? ? / 

P S Hypoestes aristata ribbon bush ? ? M ? ? ? 

P Hyptis emoryi desert lavender ? ? ? ? / L 

P Iberis gibraltarica Gibraltar candytuft M ? ? ? ? ? 

P Iberis sempervirens evergreen candy tuft M M M M M M 

S Ilex X altaclarensis 'Wilsonii' Wilson holly M M M M M M 

S Ilex aquifolium English holly L M M M M M L 

S Ilex cornuta 'Burfordii' Burford holly L M M M M M 

79




S Ilex crenata box-leaved holly M ? M M ? ? 

S Ilex dimorphophilla Okinawan holly M M M M / ? 

P Ilex integra Nepal holly ? ? ? ? ? ? 

S Ilex X meserveae blue boy/girl etc. cvs. M M M M / ? 

S Ilex verticillata winterberry ? ? ? ? ? ? 

S Ilex vomitoria yaupon L M L L M M 

P Illicium floridanum 'Alba' white Florida anise-tree M ? ? ? ? ? 

P S Impatiens sodeni (oliveri) poor man's rhododendron M / H / / / 

S Impatiens uguensis impatiens (uguensis) H ? H ? ? ? 

P Imperata cylindrica 'Rubra' Japanese blood grass H H M M ? M L 

S Indigofera decora (incarnata) Chinese indigo M ? ? ? ? ? 

P Inula ensifolia inula M ? ? ? ? ? 

S Iochroma cyanea violet tubeflower M ? M M / / 

S Iochroma fuchsioides red tubeflower M ? M M ? ? 

P Ipheion uniflorum (Tritelia) spring star flower L L L ? ? ? 

V Ipomea indica (acuminata) blue dawn flower L M L M / M 

P Ipomopsis rubra standing cypress L ? ? ? ? ? 

P Iris spp. Douglas iris hybrids L L M M H / 

P Iris spp. bearded iris L L M M M M 

P Iris spp. Siberian iris M M H ? ? ? 

P Iris spp. Japanese iris H H H H / / 

P Iris spp. Spanish/Dutch iris M M M M M M 

S Isocoma spp. (Haplopappus) goldenbush ? ? VL VL VL VL 

P Isolepis cernua (Scirpus cernuus) low bull rush H H H H H H 

P S Isoplexis chalcantha isoplexis L ? ? ? ? ? 

S Isopogon formosus rose cone flower/drumsticks L ? ? ? ? ? 

S Itea ilicifolia holly sweetspire M M M M ? ? 

Gc Iva hayesiana poverty weed VL VL VL L / / 

P Ixia spp. African corn lily L l M M ? ? 

S Ixora coccinia jungle geranium ? ? M ? / ? 

T Jacaranda mimosifolia jacaranda M M M M / M 

S V Jasminum angulare South African jasmine ? / M ? ? ? 

S V Jasminum azoricum lemon scented jasmine M ? M ? ? ? 

S V Jasminum beesianum jasmine (beesianum) M ? ? ? ? ? 

S Jasminum floridum showy jasmine L M M M / M 

Jasminum grandiflorum 

see J officinale f.grandiflorum 

S Jasminum humile Italian jasmine L M M M / M 

V Jasminum leratii jasmine (leratii) M ? M M / / 

S Jasminum mesnyi primrose jasmine L M M M / M 

S Jasminum nitidum angel wing jasmine L M M M / M 

S Jasminum nudiflorum winter jasmine L L ? ? ? ? 

S Jasminum officinale f. grandiflorum common jasmine L L M M ? ? 

S Jasminum parkeri dwarf jasmine L L M ? ? ? 

V Jasminum polyanthum pink jasmine M M M M / M 

SV Jasminum sambac Arabian jasmine M ? M ? ? M 

V Jasminum X stephanense Stephan jasmine M ? ? ? ? ? 

T Jatropha integerrima spicy jatropha ? ? L ? ? L 

T Jubaea chilensis Chilean wine palm L M L M / / 

T Juglans californica S. California black walnut M / L L / / 

T Juglans hindsii California black walnut M M / L / / 

T Juglans major Arizona walnut ? ? ? ? ? M 

T Juglans nigra eastern black walnut M M / / / / 

T Juglans regia English walnut M M M M / / 

P Juncus spp. rush H H M M ? ? L 

P Juniperus californica California juniper L L L L L L 

T Juniperus scopulorum'Tolleson' Tolleson's juniper L L M M M M 

T Juniperus spp. juniper L L L M M M 

S Justicia aurea yellow plume flower ? ? H H ? ? 

S Justicia brandegeana shrimp plant M M M M / M 

S Justicia californica chuparosa M / VL L L M 

S Justicia candicans red justicia ? ? ? ? ? ? 

80




S Justicia carnea Brazilian plume flower M H H H / H 

P Justicia leonardii justicia (leonardii) ? ? ? ? ? ? 

S Justicia sonorea Sonoran justicia ? ? ? ? ? L 

S Justicia spicigera Mexican honeysuckle / ? L L / L 

P Kalanchoe spp. kalanchoe L L L L / M 

Gc P Keckiella antirhinnoides yellow penstemmon ? ? L L / / 

Gc P Keckiella cordifolia heart-leaved penstemmon ? ? VL L / / 

V Kennedia nigricans black coral pea L ? ? ? ? ? 

V Kennedia rubicunda dusky coral pea L ? ? ? ? ? 

S Kerria japonica Japanese rose M M ? M M ? 

P Kirengeshoma koreana yellow waxbells H ? ? ? ? ? 

P Kirengeshoma palmata yellow waxbells H ? ? ? ? ? 

P Kniphofia triangularis (galpinii) coral poker M M L L / M 

P Kniphofia uvaria red hot poker M M L L / M 

P Koelaria glauca blue hair grass M ? M M M ? 

T Koelreuteria bipinnata Chinese flame tree M M M M / M 

T Koelreuteria elegans Chinese flame tree M M M M / M 

T Koelreuteria paniculata golden rain tree M M L L M M 

S Kolkwitzia amabalis beauty bush L M M M M / 

S Kunzea spp. kunzea L / M ? ? ? 

V Labab purpureus (Dolichos labab) hyacinth bean M M M ? ? ? 

T Laburnum X watereri golden chain tree M M / / / / 

P Lachenalia spp. cowslip L L ? ? ? ? 

TS Lagerstroemia X fauerei crape myrtle L L M M M M 

T S Lagerstroemia indica crape myrtle L L M M M M 

T Lagunaria patersonii primrose tree L / L L / / 

S Lambertia intermis lambertia L ? ? ? ? ? 

P Gc Lamiastrum galeobdolon yellow archangel M M M ? ? ? 

Gc Lamium maculatum spotted deadnettle M M M ? ? ? 

Gc Lampranthus spp. ice plant (Lampranthus) L L L L / L 

S Lantana camara lantana L L L L / M 

S Gc Lantana montevidensis (sellowiana) trailing lantana L L L L / M 

T Larix decidua European larch M / / / / / 

P Larrea tridentata creosote VL VL VL L L L 

P Gc Laurentia fluviatilis blue star creeper M M M M ? M 

T S Laurus nobilis sweet bay L L L L M M 

T Laurus 'Saratoga' Saratoga laurel L L L L M M 

S Lavandula spp. lavender L L L L M M 

S Lavatera assurgentiflora tree mallow L M L L / M 

S Lavatera hybrids lavatera L L M M ? ? 

S Lavatera maritima bush mallow L L M M ? ? 

S Lechenaultia formosa orange L ? ? ? ? ? 

Lemaireocereus thurberi (See 

Stenocereus thurberi) 

S Leonotis leonurus lion's tail L L L L M M 

P Leontopodium alpinium eidelweiss M M ? ? ? ? 

S Lepechinia hastata Mexican pitcher sage L ? M ? ? ? 

T S Leptospermum laevigatum Australian tea tree L L L L / / 

T S Leptospermum petersonii lemon scented tea tree L ? M M / / 

T S Leptospermum polygalifolium tea tree ? ? ? ? / / 

T Leptospermum rotundifolium tea tree L L ? L / / 

S Gc Leptospermum rupestre (humifusum) tea tree L ? ? ? / / 

T S Leptospermum scoparium New Zealand tea tree M M M M / / 

T Leucadendron argenteum Silver tree L / L / / / 

T Leucadendron galpinii Galpin's leucadendron ? / ? ? ? ? 

T Leucadendron hybrids hybrid leucadendron L ? ? ? ? ? 

P Leucanthemum X superbum Shasta daisy M M M M M M 

P Leucojum aestivum summer snowflake ? L M M ? ? 

S Leucophyllum spp. purple sage, Texas ranger etc. L L L L L L 

S Leucospermum cordifolium nodding pincushion / / L / / / 

S Leucothoe fontanesiana drooping laurel M ? ? ? ? ? 

81




P Lewisia columbiana rupicola columbia lewisia L / ? ? ? ? 

P Lewisia cotyledon bitter root L / ? ? ? ? 

P Lewisia hybrids lewisia L / ? ? ? ? 

P Leymus spp. (also see Elymus spp.) wild rye VL VL M M ? ? 

P Liatris spicata gay feather M M M M M M 

P Libertia spp. libertia L ? M ? ? ? 

P Ligularia tussilaginea (See Farfugium 

japonicum) 

S Ligustrum japonicum Japanese privet M M M M M M 

T Ligustrum lucidum glossy privet L L M M M M L 

S Ligustrum ovalifolium California privet L L M M ? ? 

S Ligustrum X vicaryi golden privet L L M M ? ? 

P Lilium (garden hybrids) lily M M M M M M 

P Limonium commune var. californicum coastal statice L L L M / / 

P Limonium perezii statice L L L M / M L 

P Limonium speciosum (See Goniolemon 

incanum) 

P Limonium tataricum (See Goniolemon 

tataricum) 

P Linaria purpurea toadflax L M L M M M 

P Linaria supina toadflax ? ? ? ? ? ? 

P Linum spp. flax VL VL M ? M M 

T Liquidambar styraciflua sweet gum M M M M M / 

T Liriodendron tulipifera tulip tree M H M H / / 

P Liriope spp. lilyturf M M M M M M 

T Lithocarpus densiflorus tanbark oak L / L L / / 

T Lithocarpus edulis (Pasania edulis) Japanese false oak 

P Lithodora diffusa heavenly blue M M / / / / 

T Livistona australis Australia fountain palm / / M M / / 

T Livistona chinensis Chinese fan palm ? / M M / / 

T Livistona mariae central Australian fan palm / / ? ? ? ? 

T Livistona rigida livistona (rigida) / / ? ? ? ? 

P Lobelia 'Brightness' brightness lobelia H H H ? ? ? 

P Lobelia chinensis lobelia (chinensis) H ? ? ? ? ? 

P Lobelia fulgens Mexican cardinal flower H H H ? ? ? 

S P Lobelia laxiflora Mexican bush lobelia ? ? VL VL ? M 

S Lobelia ricardii lobelia (ricardii) ? ? M ? ? ? 

P Lobelia richmondensis perennial lobelia M ? M ? ? ? 

P Lobelia siphilitica great blue lobelia ? ? ? ? ? ? 

S Lobostemon fruiticosus eight-day-healing bush / ? L ? ? ? 

P Lomandra longifolia spiny headed mat rush ? ? M ? ? ? 

V Lonicera confusa honeysuckle (confusa) ? ? M ? ? ? 

V Lonicera hildebrandiana giant Burmese honeysuckle M M M M M M 

S Lonicera hispidula honeysuckle (hispidula) L ? L VL ? ? 

V Lonicera japonica Japanese honeysuckle M M L L M M L 

V Gc Lonicera japonica 'Halliana' Hall's honeysuckle M M L L M M L 

S Lonicera nitida box honeysuckle L M / M / / 

V Lonicera periclymenum flowering woodbine L L ? ? ? ? 

V Lonicera sempervirens trumpet honeysuckle M M / M M M 

S Lonicera subspicata chaparral honeysuckle L ? L VL ? ? 

V Lonicera tatarica tatarian honeysuckle M ? ? ? ? ? 

T Lophostemon confertus Brisbane box M / M M / / 

S Loropetalum chinense fringe flower L M M ? ? ? 

Gc Lotus corniculatus birdsfoot trefoil L M M M / M L 

P Lotus scoparius deer weed VL VL VL VL L L 

S T Luculia pinceana luculia M / ? ? ? ? 

S Luma apiculata palo Colorado M / M M / / 

S Lupinus albifrons silver lupine VL L / L / / 

S Lupinus arboreus coastal bush lupine L / L / / / L 

S Lupinus excubitus grape soda lupine VL VL ? ? ? ? 

P Lupinus (Russell hybrids) Russell lupines M M / / / / 

82




P Lupinus sparsiflorus arroyo lupin ? ? ? ? ? ? 

P Luzula nivea snowy woodrush M ? ? ? ? ? 

P Luzula purpurea purple woodrush M ? ? ? ? ? 

P Luzula sylvatica greater woodrush M ? ? ? ? ? 

P Lychnis alpina alpine campion M M ? ? ? ? 

P Lychnis chalcedonica Maltese cross M M M M M M 

P Lychnis coronaria rose campion/crown pink L L L L M M 

S Lycianthus rantonnetii Paraguay nightshade/blue potato M M M M / M 

bush M 

S Lycium exertum boxthorn / ? ? ? ? ? 

S Lycium fremontii wolfberry / L L L L L 

T Lyonothamnus floribundus Catalina ironwood L / VL L / / 

T S Lysiloma candida palo blanca / / ? ? / M 

T S Lysiloma microphylla var. thornberi feather bush ? / L L / M 

P Gc Lysimachia spp. loosestrife/moneywort H H H H / / L 

T Macadamia spp. macadamia nut M / M M / / 

V Macfadyena unguis-cati cat's claw L L L L L L 

S Mackaya bella forest bell bush M ? M M / / 

P Macleaya spp. plume poppy M ? M ? ? ? 

T Magnolia grandiflora southern magnolia M M M M / H 

T Magnolia hybrids hybrid magnolias M M ? ? ? ? 

T S Magnolia X loebneri loebner magnolia M M ? ? ? ? 

T S Magnolia sieboldii oyama magnolia M M ? ? ? ? 

T Magnolia X soulangiana saucer magnolia M M M M / / 

T Magnolia stellata star magnolia M M M M / / 

T Magnolia X veitchii veitch magnolia M M ? ? ? 

S Mahonia aquifolium Oregon grape M M M M M M 

S Mahonia bealei leatherleaf mahonia M M M M M M 

S Mahonia fortunei chinese mahonia M M ? ? ? ? 

S Mahonia 'Golden Abundance' golden abundance mahonia L L L M M M 

S Mahonia lomariifolia Chinese holly grape M M L M M M 

S Mahonia nervosa longleaf mahonia M ? ? M ? ? 

S Mahonia nevinii Nevin mahonia VL L L L M M 

S Mahonia pinnata & cvs. California holly grape L L M M M M 

Gc Mahonia repens creeping mahonia L L L M M / 

P Maianthemum dilatatum May lily M H ? ? ? ? 

S Maireana sedifolia pearl bluebush ? ? L ? ? ? 

S Malacothamnus clementinus San Clemente Island bush mallow 

S Malacothamnus fasciculatus bush mallow VL L VL L / / 

S Malacothamnus fremontii Fremont's bush mallow VL L ? ? ? ? 

Gc Maleophora spp. ice plant (Maleophora) L L L L / L L 

S Malosma laurina (Rhus laurina) laurel sumac VL L VL L / / 

T Malus spp.(edible) apple M M M M M / 

T Malus hybrids crabapple M M / M M / 

S Malvaviscus arboreus Turk's cap M ? M M / / 

V Mandevilla laxa Chilean jasmine M / M M / M 

S Mandevilla splendens mandevilla M / M M / M 

V Mandevilla cvs. 'Alice Dupont' etc. M / M H / H 

Mandevilla suaveolens (See M. laxa) 

P Manfreda spp. manfreda L ? ? ? ? ? 

T Markhamia lutea (hildebrandtii) markhamia ? / M / / / 

V Mascagnia lilacina purple orchid vine ? ? ? ? ? M 

V Mascagnia macroptera yellow orchid vine ? ? ? ? ? M 

P Matteuccia struthiopteris ostrich fern ? ? M H ? ? 

Maurandya antirriniflora (See Asarina 

antirriniflora) 

Maurandya barclaiana (See Asarina 

barclaiana) 

Maurandya erubescens (See Asarina 

erubescens) 

83




T Maytenus boaria mayten tree M M M M / / 

S T Maytenus phyllanthoides mangle dulce ? ? ? ? ? ? 

P Gc Mazus reptans mazus M H M H ? ? 

T S Melaleuca armillaris bracelet honey-myrtle VL / L M / M 

T S Melaleuca decussata totem poles (lilac melaleuca) VL / L M / M 

T S Melaleuca elliptica granite honey-myrtle VL / L M / M 

T Melaleuca ericifolia heath melaleuca L / ? ? ? ? 

S Melaleuca fulgens melaleuca (fulgens) L ? L M / M 

S Melaleuca huegelii chenile honey-myrtle ? / L M / M 

S Melaleuca incana grey honey-myrtle L ? L M / M 

T Melaleuca lanceolata black tea ? L ? L / / 

T Melaleuca linariifolia flax leaf paper bark L L L L / / 

T Melaleuca nesophila pink melaleuca L L L L / / 

T Melaleuca quinquinervia (See 

Melaleuca virididfolia var rubifolia) 

T Melaleuca rhaphiophylla swamp paper bark ? / ? L / / 

T Melaleuca squamea swamp honey-myrtle ? ? L M / M 

T Melaleuca styphelioides prickly-leaved paperback L L L M / M 

T Melaleuca thymifolia thyme honey-myrtle L L ? ? ? ? 

T Melaleuca viridiflora var. rubiflora cajeput tree L L M M / M L 

S Melaleuca wilsonii Wilson melaleuca L L ? ? ? ? 

P Melampodium leucanthum blackfoot daisy L / ? L L L 

T Melia azedarach chinaberry VL L VL L L L 

S Melianthus major honey bush L M M M / M 

P Gc Melissa officinalis lemon balm ? M M ? ? ? 

Gc P Mentha spp. mint L M M M M M L 

V Merremia aurea merremia (aurea) ? ? ? ? / M 

V Merremia quinquefolia merremia (quinquefolia) ? ? ? ? / M 

T Meryta sinclairii puka / / M ? / / 

T Metasequoia glyptostroboides dawn redwood H H H H / / 

T Metrosideros excelsa New Zealand Christmas tree L / M M / / 

S Metrosideros collinia Lehua of Hawaii ? ? ? ? ? ? 

Metrosideros tomentosa (see M. 

excelsa) 

T Michelia champaca fragrant Himalayan champaca M ? M ? / / 

T Michelia doltsopa wong-lan M M M M / / 

S Michelia figo banana shrub M M M H / H 

T Michelia X foggi 'Jack Fogg' Jack Fogg michelia M ? ? ? ? ? 

S Gc Microbiota decussata Siberian cypress M ? ? ? ? ? 

P Microlepia strigosa lace fern M / M H / / 

P Milium effusum golden wood millet M ? ? ? ? ? 

V Milletia reticulata evergreen wisteria M ? M M / / 

V Milletia taiwanensis Chinese evergreen wisteria H ? ? ? ? ? 

S Mimulus spp. (shrubby) monkey flower L L L L / / 

P Mimulus spp. (herbaceous) monkey flower H H H H / / 

P Mirabilis california wishbone bush ? ? M ? ? ? 

P Mirabilis jalapa four o'clock VL L / L M M 

P Mirabilis multiflora giant four o'clock ? L ? ? ? ? 

P Miscanthus sinensis eulalia grass H H M M M M 

P Miscanthus transmorrisonensis evergreen eulalia H H M M M M 

P Molinia caerulea Moor grass M ? ? ? ? ? 

P Monarda didyma bee balm M M M M M M 

P Monardella linoides ssp. viminea San Diego willowy mint L ? M ? ? ? 

P Monardella macrantha scarlet monardella L ? ? ? ? ? 

P Monardella odoratissima mountain pennyroyal / ? M ? ? ? 

P Monardella villosa coyote mint VL VL VL L ? M 

P Monochaetum volcanicum monochaetum M ? ? ? ? ? 

S Montanoa grandiflora daisy tree M ? M ? ? ? 

P Moraea spp. (summer growing) moraea M M ? ? ? ? 

P Moraea spp.(winter growing) morea VL VL ? ? ? ? 

P Morina longifolia whorlflower M ? ? ? ? ? 

84




T Morus alba white mulberry M M M M M M 

Gc V Muehlenbeckia axillaris creeping wire vine M M M M / M 

Gc V Muehlenbeckia complexa mattress vine L L M M / M 

P Muhlenbergia capillaris hairy awn muhly L ? M ? M M 

P Muhlenbergia dumosa bamboo muhly L ? M M M M 

P Muhlenbergia emersleyi bull grass M ? ? ? ? M 

P Muhlenbergia lindheimeri Lindheimer muhly L ? ? M ? M 

P Muhlenbergia pubescens soft muhly L ? ? ? ? M 

P Muhlenbergia rigens deer grass L M L M M M 

S Murraya paniculata orange jessamine / H M M / M 

P Muscari macrocarpum grape hyacinth VL VL VL VL M H 

S P Musa spp. banana H H H H / H 

T S Myoporum laetum myoporum L M M M / / L 

S Gc Myoporum X 'Pacificum' pacifica saltbush L L L M / / 

S Gc Myoporum parvifolium & cvs. myoporum L L L L / M 

P Myosotis scorpioides forget-me-not M M / M / H L 

S Myrica californica Pacific wax myrtle L L L M / / 

S Myrica pennsylvanica bayberry M M ? ? / / 

S Myrica rubra Chinese strawberrry tree ? ? ? ? ? ? 

S Myrsine africana African boxwood L L L M / / 

S Myrtus communis true myrtle L L L M M M 

T Nageia nagi (Podocarpus nagi) Nageia M M M M ? M 

S Nandina domestica heavenly bamboo L L L M M M 

S Nandina domestica 'Purpurea' heavenly bamboo (Nana) M M M M M M 

P Narcissus spp. daffodil VL VL L L L L 

P Nassella cernua nodding needlegrass VL L VL VL VL L 

P Nassella lepida foothill needlegrass VL L VL VL VL L 

P Nassella pulchra purple needlegrass VL L VL VL VL L 

P Nassella tenuissima Texas needle grass ? ? VL VL VL L 

P Nauplius sericeus (Asteriscus sericeus) Canary island daisy L ? VL / / / 

T Neodypsis decaryi triangle palm ? / M M / / 

P Neomarica caerulea poor man's orchid L ? M ? ? ? 

P Nepeta spp. catmint/catnip L M M M M M 

P Nephrolepis cordifolia southern sword fern M M M M M M 

P Nephrolepis exaltata Boston fern / M M M M M 

P Nerine spp. nerine L L L L M M 

S Nerium oleander oleander L L L L M M L 

P Nierembergia hippomanica cup flower M M M M / M 

TS Nolina recurvata (Beaucarnea bottle palm / / L L / L 

recurvata) 

S P Nolina spp. bear grass VL VL VL VL L L 

T Nyssa sylvatica sour gum/tupelo M M M H / / 

S Ochna serrulata bird's eye bush L / M M / / 

S Odontonema strictum firespike ? ? ? ? ? ? 

Gc Odontospermum hybrida gold coin ? L M M ? ? 

P Oenanthe javanica water dropwort H ? ? ? ? ? L 

Oenothera berlandieri (See Oenothera 

speciosa) 

P Oenothera caespitosa tufted (white) evening primrose L ? / L L L 

Oenothera cherianthifolia (See 

Camissonia cherianthifolia) 

P Oenothera fruiticosa golden sundrops M ? VL / / / 

Oenothera missouriensis (See O. 

macrocarpa) 

P Gc Oenothera macrocarpa Ozark sundrops M M L ? L L 

P Oenothera pallida evening primrose (pallida) L ? L ? L L 

P Oenothera rosea evening primrose (rosea) M ? L ? ? ? 

Gc P Oenothera speciosa Mexican/white evening primrose L L L L M M 

Gc P Oenothera speciosa 'Rosea' pink evening primrose L L L L M M 

Gc P Oenothera stubbei Baja evening primrose L L L L L L 

85




Oenothera tetragona (See O. fruticosa 

spp. glauca) 

T Olea europaea olive VL VL L L M M L 

T Olmediella betschleriana Guatemalan holly M / M M / / 

T Olneya tesota desert ironwood / / / / L L 

P Omphalodes cappadocica navelwort M M M ? ? ? 

P Omphalodes verna creeping forget-me-not M ? ? ? ? ? 

P Onoclea sensibilis sensitive fern H H M ? ? ? 

P Ophiopogon clarkii Clark lily turf M M M M M M 

P Ophiopogon jaburan giant lily turf M M M M M M 

P Ophiopogon japonicus mondo grass M M M M M M 

P Ophiopogon planiscapus var. 

black mondo grass M M M M M M 

nigrescens 

S Opuntia spp. prickly pear/cholla VL VL VL L L L 

P Origanum spp. dittany/oregano etc. M M L L M L 

P Ornithogalum thyrsoides chincherinchee ? ? L L ? ? 

P Orthosiphon labiatus shell bush M ? ? ? ? ? 

P Orthrosanthus chimboracensis orthrosantus L ? ? ? ? ? 

centroamericanus 

P Orthrosanthus multiflorus orthrosantus L ? ? ? ? ? 

S Osmanthus spp. sweet olive/osmanthus M M M M M M 

P Osmunda cinnamomea cinnamon fern H H H H / / 

P Osmunda regalis royal/flowering fern H H H ? / / 

Gc Osteospermum spp. African daisy L L L L / M 

P S Otatea acuminata (aztecorum) Mexican weeping bamboo M ? M M / H 

P Otholobium fruiticans blue cape pea ? ? M ? ? ? 

P Oxalis spp. sorrel/shamrock M M M M ? ? 

P Oxera pulchella royal climber ? / M M / / 

T Oxydendrum arboreum sourwood tree M M / ? ? / 

P Oxypetalum caeruleum (See Tweedia 

caesulea) 

S Ozothamnus rosemarinifolius 

ozothamnus M ? L ? ? ? 

(Helichrysum) 

T Pachycormis discolor elephant tree ? ? L ? / L 

T Pachypodium lamerei Madagascar palm ? / L M / M 

Gc Pachysandra terminalis Japanese spurge M M M / M / 

P Paeonia spp. peony M M / / / / 

V Pandorea jasminoides bower vine M / M M / / 

V Pandorea pandorana wonga wonga vine M / M M / / 

P Panicum virgatum cvs. switch grass M ? ? ? ? ? 

P Panicum (native spp.) switch grass ? ? L L VL VL 

P Papaver orientale oriental poppy M M M M M H 

P Papaver pilosum poppy L / M ? ? ? 

P Parahebe spp. veronica/speedwell M ? M ? ? ? 

T Parkinsonia aculeata Mexican palo verde/ Jerusalem VL VL L L L L 

thorn 

T Parkinsonia florida (Cercidium floridum) blue palo verde VL VL VL L / L 

T Parrotia persica Persian witch hazel M ? / ? ? / 

V Parthenocissus henryana silver vein creeper M ? M ? ? ? 

Gc V Parthenocissus quinquefolia Virginia creeper M M M M M M 

Gc V Parthenocissus tricuspidata Boston ivy M M M M M M 

Pasania edulis (See Lithocarpus edulis) 

V Passiflora spp. passion vine M M M M / M 

P Pattersonia drummondii pattersonia M ? M ? ? ? 

T Paulownia kawakamii sapphire dragon tree ? ? M M ? / 

T Paulownia tomentosa empress tree M H M M ? / 

S Pavonia praemorsa yellow mallow ? ? M ? ? ? 

P Pelargonium cordifolium heartleaf geranium M ? M M ? ? 

P Pelargonium domesticum Martha Washington pelargonium M M M M / M 

86




P Pelargonium X hortorum garden geranium L L M M / M 

Gc P Pelargonium peltatum ivy geranium M M M M / M 

P Gc Pelargonium sidoides geranium (sidoides) M ? L ? ? ? 

P Pelargonium tomentosum peppermint-scented geranium M M L M ? ? 

P Pellaea mucronata bird's foot fern L ? M ? ? ? 

P Pellaea rotundifolia button fern M ? M ? ? ? 

P Pennisetum alopecuroides black pennisetum L L L L L L 

P Pennisetum orientale Chinese fountain grass M ? L ? ? ? 

Pennisetum machrostachym (see P. 

setaceum) 

P Pennisetum setaceum fountain grass L L L L L L L L 

P Pennisetum setaceum cvs, purple/burgundy fountain grass M L M L L L 

P Penstemon hybrids penstemon (hybrids) M M M M M M 

P Penstemon wild spp. penstemon (wild) L L L L L L 

Pentapterygium (See Agapetes) 

S Perityle incana Guadalupe island rock daisy / ? ? ? ? / 

Pernetteya mucronata (See Gaultheria 

mucronata) 

S P Perovskia spp. Russian sage M M M M L L 

T Persea americana avocado M M M M / / 

Petalostemon purpureum (See Dalea 

gattingeri) 

V Petrea volubilis queens wreath ? / M M ? ? 

P Phalaris spp. (ornamental) ribbon grass M M M M / / L 

S Philadelphus lewisii californicus wild mock orange M ? M M ? ? 

S Philadelphus mexicanus evergreen mock orange L M M M M M 

S Philadelphus X virginalis double mock orange M M M / / / 

S P Philodendron bipinnatifidum (selloum) tree philodendron M M M M / M 

P Phlebodium aureum (Polypodium rabbit's foot fern M ? M ? ? ? 

aureum) 

P Phlomis caballeroi phlomis (caballeroi) ? ? L L ? ? 

S P Phlomis cashmeriana phlomis (cashmeriana) ? ? L L ? ? 

P Phlomis cretica phlomis (cretica) ? ? L L ? ? 

S P Phlomis fruticosa Jerusalem sage L L L L M M 

S P Phlomis italica phlomis (italica) L M L L ? ? 

P Phlomis lanata phlomis (lanata) L ? L L ? ? 

P Phlomis purpurea phlomis (purpurea) ? ? L L ? ? 

P Phlomis russeliana phlomis (russeliana) L ? M M ? ? 

S Phlomis tuberosa phlomis (tuberosa) M ? L L ? ? 

P Phlox (shrubby cvs.) phlox M M M M M M 

Gc P Phlox subulata moss pink M M / / M M 

T Phoenix canariensis Canary Island date palm L L L L M M 

T Phoenix dactylifera date palm L L L L M M 

T Phoenix reclinata Senegal date palm / / M M / M 

T Phoenix roebelenii pigmy date palm L / M M / M 

T Phoenix rupicola cliff date palm / / M M / / 

S Phormium hybrids flax L M M M / M 

S Phormium tenax New Zealand flax L L L M / M 

T S Photinia X fraseri Fraser photinia M M M M M M 

T S Photinia serratifolia (P. serrulata) Chinese photinia M M / M M M 

S Phygelius X rectus cape fuchsia M ? M ? ? ? 

Gc Phyla nodiflora (Lippia nodiflora) cape weed L M L L / M L 

Phyllitis scolopendrium (See Asplenium 

scolopendrium) 

S Phyllostachys spp. bamboo (Phylostachys) L L M M M M 

P Physostegia virginiana obedient plant M M M M M M 

T Picea abies Norway spruce M M M / / / 

T Picea glauca Alberta spruce M M / / M / 

T Picea mariana black spruce ? ? ? ? ? / 

T Picea omorika Serbian spruce ? ? ? ? ? / 

87




T Picea orientalis oriental spruce ? ? ? ? ? / 

T Picea pungens Colorado spruce M M M M M / 

S Pieris formosa var.forestii Chinese pieris M M / / / / 

S Pieris japonica (taiwanensis) lily-of-the-valley shrub M M / / / / 

S Pimelea ferruginia rice flower M / / / ? ? 

S Pimelea prostrata rice flower M / / / ? ? 

P Pinellia ternata pinellia M ? M ? ? ? 

T Pinus attenuata knobcone pine L L L L / / 

T Pinus X attenuradiata knobcone-Monterey pine M / L M / / 

T Pinus brutia Calabrian pine L L L L M M 

T Pinus brutia ssp. eldarica eldarica pine L L L L L L 

T Pinus canariensis Canary Island pine L L L M M M 

T Pinus contorta beach pine M M / / / / 

T Pinus coulteri Coulter pine L L L L M / 

T Pinus densiflora Japanese red pine M M / M / / 

T Pinus edulis pinyon pine L L VL L L / 

Pinus eldarica (See P brutia spp. 

eldarica) 

T Pinus flexilis limber pine ? ? L ? ? ? 

T Pinus halepensis Aleppo pine L L L L L L 

T Pinus heldreichii Bosnian pine M ? ? ? ? ? 

T Pinus jeffreyi Jeffrey pine L L / / / / 

Pinus leucodermis (See P. heldreichhi) 

T Pinus monophylla single leaf pinyon pine L / L L L / 

T Pinus montezumae Montezuma pine L ? L L / / 

S Pinus mugo mugo pine L L / M M / 

T Pinus muricata bishop pine M M L / / / 

T Pinus nigra Austrian black pine M M / M M / 

T Pinus parviflora Japanese white pine M M / / ? / 

T Pinus patula Jelecote pine M M M M M M 

T Pinus pinaster cluster pine M M L / / / L 

T Pinus pinea Italian stone pine L L L L M M L 

T Pinus ponderosa ponderosa pine L L / L / / 

T Pinus radiata Monterey pine M / M M / / L 

T Pinus roxburghii chir pine M M M M M M 

T Pinus sabiniana foothill/Gray pine VL VL VL L / / 

T Pinus strobus eastern white pine M ? / / ? / 

T Pinus sylvestris Scotch pine M M / M / / 

T Pinus thumbergii Japanese black pine M M M M M M 

T Pinus torreyana Torrey pine L L L M / / 

T Pisonia umbellifera bird catcher tree ? / M ? / / 

T Pistacia chinensis Chinese pistache L L M M M M 

T S Pistacia lentiscus mastic tree VL ? M M ? ? 

T Pistacia vera pistachio L L M M / / 

T Pithecellobium flexicaule Texas ebony ? ? / ? / L 

T Pithecellobium pallens tenaza ? ? ? ? L L 

V Pithecoctenium crucigerum pithecoctenium ? ? M M ? ? 

T S Pittosporum crassifolium evergreen pittosporum M M M M / / 

T S Pittosporum eugenioides tarata M M M M / / 

T Pittosporum phillyraeoides willow pittosporum M M L L / M 

T S Pittosporum rhombifolium Queensland pittosporum M / M M / / 

T S Pittosporum tenuifolium tawhiwhi M M M M / / 

S Pittosporum tobira mock orange L M M M M M 

S Pittosporum tobira 'Wheelers Dwarf' dwarf pittosporum M M M M M M 

T Pittosporum undulatum victorian box M / M M / / 

T Platanus X acerifolia and cvs. London plane M M M M H H 

T Platanus occidentalis 'Glabrata' Texas sycamore ? ? ? ? ? ? 

T Platanus racemosa California sycamore M M M M H H 

T Platanus wrightii Arizona sycamore M ? M M H H 

S Platycladus orientalis oriental arborvitae M M M M M M 

88




P Platycodon grandiflorus balloon flower M M M M M M 

S Plecostachys serpyllifolia (Helichrysum) straw flower L L L L M M 

S P Plectranthus spp. Swedish ivy M / M M / / 

Gc 

P Pleioblastus spp. dwarf bamboo M ? M ? ? ? 

S Plumbago auriculata (campense) cape plumbago L M M M / M 

S Plumbago scandens summer snow ? ? ? M / L 

S Plumeria rubra frangipani / / L / / M 

P Poa costineata Australian blue grass M ? ? ? ? ? 

Podocarpus gracilior (See Afrocarpus 

gracillior) 

T Podocarpus henkelii long leaf yellow wood M H M M M / 

T Podocarpus latifolius yellow wood M ? M / / / 

T S Podocarpus macrophyllus yew pine M M M M M M 

Podocarpus nagi (See Nageia nagi) 

S Podocarpus nivalis alpine totara M ? ? ? ? ? 

T Podocarpus totara totara ? ? M M ? ? 

V Podranea ricasoliana pink trumpet vine / M M M / M 

P Polemonium spp. Jacob's ladder H H M M ? ? 

P Poliomintha longiflora Mexican oregano L ? ? ? L L 

P Polyanthes tuberosa tuberose M M L ? L L 

S Polygala X dalmaisiana sweet pea shrub L M M M / / 

P Polygonatum odoratum (japonicum) Soloman's seal H / M ? ? ? 

V Polygonum aubertii silver lace vine L L L L M M 

P Polypodium (native spp.) plypody VL ? ? ? ? ? 

P Polypodium (subtropical spp.) polypody M ? ? ? ? ? 

P Polystichum californicum sword fern L M M H / / 

P Polystichum munitum western sword fern M M M H / H 

P Polystichum polyblepharum Japanese lace fern M H H H M M 

P Polystichum X setigerum Alaskan fern M H H H M M 

T Populus alba 'Pyramidalis' bolleana poplar M M M M H H 

T Populus balsamifera balsam/balm of Gilead poplar M M M M H H 

T Populus X canadensis Carolina poplar H H ? M H H 

T Populus fremontii western cottonwood M M M M H H 

T Populus 'Mohavensis' Mohave poplar ? ? ? ? M M 

T Populus nigra 'Italica' Lombardy poplar M M M M H H 

T Populus 'Red Caudina' cottonless cottonwood ? ? ? ? ? ? 

T Populus trichocarpa black cottonwood H H M M H / 

S P Portulacaria afra elephant's food L L L L / L 

S Potentilla fruticosa cvs. cinquefoil M M / / M / 

Gc Potentilla neumanniana 

spring cinquefoil M M M M / M 

(tabernaemontani) 

P Gc Pratia angulata pratia H H H H / / 

T Prosopis alba Argentine mesquite / L L L M M 

Prosopis chilensis (See P. glandulosa) 

T Prosopis glandulosa Chilean mesquite / L L L L L 

T Prosopis glandulosa glandulosa Honey mesquite / L L L L L 

T Prosopis juliflora Arizona mesquite ? ? L L L L 

T Prosopis pubescens screwbean mesquite / L L L M M 

T Prosopis velutina velvet mesquite / L L L M M 

S Prostanthera denticulata mint bush L ? ? ? ? ? 

S Prostanthera lasianthos victorian dogwood M ? ? ? ? ? 

S Prostanthera rotundifolia round leaf mint bush L M L M / / 

S P Protea spp. protea M / M M / / 

Gc P Prunella spp. self heal M M M M ? ? 

T S Prunus caroliniana Carolina laurel cherry L L M M M M 

T S Prunus ilicifolia holly leaf cherry L L VL VL / / 

T S Prunus lauroceracus English laurel M M / H / / 

T S Prunus lusitanica Portugal laurel L L / / / / 

89




T S Prunus lyonii Catalina cherry L L L L / / 

T Prunus sargentii Sargent cherry M ? M ? ? / 

T Prunus spp. (edible) almond L M M M M / 

apricot M M M M M / 

T Prunus spp. (edible) cherry M M M M M / 

peach M M M M M / 

peach (low chill only) M M M M / M 

nectarine M M M M M / 

plum M M M M M / 

plum (low chill only) L M M M / M 

prune L M M M M / 

T Prunus spp. (ornamental) flowering cherry M M M M M / 

flowering peach L M M M M / 

flowering plum L M M M M M 

T Pseudobomax ellipticum shaving brush ? ? L ? / L 

V Pseudogynoxys chenopodiodes Mexican flame vine M M M ? ? ? 

(Senecio) 

T Pseudolarix kaempheri golden larch ? ? / / ? / 

T S Pseudopanax lessonii houpara M ? M / / ? 

S Pseudosasa japonica arrow bamboo M ? M M ? ? 

P Pseudosasa japonica tsutsumiana dwarf arrow bamboo M ? M M ? ? 

Psidium cattleianum (See P. littorale var. 

longipes) 

S T Psidium guajava common guava / / M / / M 

S T Psidium littorale var. longipes strawberry guava M M M / / M 

S P Psilostrophe cooperi paper flower ? ? ? ? L L 

S P Psilostrophe tagetina paper flower ? ? ? L L L 

S Psoralea pinnata blue pea M ? L M ? ? 

S Psorothamnus spinosa (Dalea spinosa) smoke tree / L / L L L 

P Pteris spp. brake fern M M M H H / 

P Pulmonaria spp. lungwort M H / ? ? ? 

P Pulsatilla vulgaris (Anemone pulsatilla) Pasque flower M M \ ? ? ? 

T Punica granatum pomegranate L L M M M M 

S Punica granatum 'Nana' dwarf pomegranate L L M M M M 

P Puya spp. puya VL ? L L / M 

S Gc Pyracantha spp. firethorn L L L M M M L 

P Pyrethropsis hosmariense Moroccan daisy L ? L ? ? ? 

Pyrethrum roseum (See Tanacetum 

coccinium) 

V Pyrostegia venusta flame vine / / M M / M 

P Pyrrosia spp. felt fern L / L ? ? ? 

T Pyrus calleryana cultivars Callery pear M M M M M M 

T Pyrus communis edible pear M M M M M / 

T Pyrus kawakamii evergreen pear M M M M M M 

T Quercus agrifolia coast live oak VL VL L L / M 

T S Quercus berberidifolia California scrub oak VL VL VL VL L / 

T Quercus buckleyi Texas red oak ? ? / ? ? ? 

T Quercus chrysolepis canyon live oak VL L L L / / 

T Quercus coccinea scarlet oak M M / M / / 

T Quercus douglasii blue oak VL VL VL L / / 

T S Quercus dumosa Nutall's scrub oak VL VL VL VL L / 

T Quercus engelmannii mesa oak / L L L / / 

T Quercus fusiformis escarpment live oak ? ? ? ? ? L 

T Quercus ilex holly oak L L L L M M 

T Quercus kelloggii California black oak L M / M / / 

T Quercus lobata valley oak L L / M / / 

T Quercus muhlenbergii chinquapin oak L ? ? L L M 

T Quercus palustris pin oak M M M M / / 

T Quercus robur English oak M M ? M ? / 

90




T Quercus rubra red oak M M / M / / 

T Quercus shumardii Shumard red oak M M ? / / / 

T Quercus suber cork oak L L L L L L 

T Quercus texana Spanish oak L ? ? L L M 

T Quercus tomentella island oak L ? L / / / 

T Quercus virginiana southern live oak M M M M M M 

T Quercus wislizeni interior live oak VL VL VL VL M / 

T Quillaja saponaria soapbark tree VL L L ? ? ? 

T Radermachera sinica Asian bell flower / / M / / / 

P Ranunculus californicus California buttercup VL VL VL VL ? ? 

P Ranunculus cortusaefolius buttercup L ? L ? ? ? 

P Ranunculus repens creeping buttercup H M L ? ? ? 

P Raoulia australis golden scabweed L / / ? ? ? 

P Ratibida columnifera Mexican hat M ? L ? ? ? 

T Ravanea rivularis ravanea / / M M / / 

P Rehmannia elata Chinese foxglove H H M H M M 

P Reineckia carnea reineckia M ? ? ? ? ? 

Gc Rhagodia deltophylla rhagodia L ? VL ? ? ? 

S Rhamnus alaternus Italian buckthorn L L L M / / 

S Rhamnus californicus coffeeberry L L VL L / M 

S Rhamnus croceus redberry L L VL L / M 

S Rhamnus croceus ilicifolia hollyleaf redberry L L VL L / M 

S Rhaphiolepis indica Indian hawthorne L L M M M M 

T Rhaphiolepis 'Majestic Beauty' majestic beauty L L M M M M 

S Rhaphiolepis umbellata Yeddo hawthorne L L M M ? ? 

S Rhapis excelsa lady palm / / M M / / 

S Rhododendron spp. azalea M M H H / / 

S Rhododendron spp. rhododendron M M H H / / 

P Rhodohypoxis spp. rose grass M ? L ? ? ? 

P Rhodophiala bifida rhodophiala L ? ? ? ? ? 

V Rhoicissus capensis evergreen grape M / M M / M 

T S Rhopalostylis baueri Norfolk palm ? / M M / / 

T S Rhopalostylis sapida Nikau palm ? / H H / / 

S Gc Rhus aromatica fragrant sumac ? ? ? ? ? ? 

S Rhus choriophylla evergreen sumac ? ? ? ? ? ? 

S Rhus integrifolia lemonade berry L L VL L / / 

T Rhus lancea African sumac L L L L M M 

T Rhus lanceolata prairie flameleaf sumac ? ? ? ? L L 

Rhus laurina (see Malosma laurina) 

S Rhus lentii pink-flowering sumac / ? L ? ? ? 

S Rhus microphylla littleaf sumac ? ? ? ? ? ? 

S Rhus ovata sugar bush L L VL L M M 

S Rhus trilobata squawbush L L L L L / 

S T Rhus typhina staghorn sumac L L L ? L / 

S Rhus virens evergreen sumac ? ? ? ? ? ? 

S Rhynchelytrum neriglume ruby grass ? ? ? ? ? ? 

S Ribes aureum golden currant L L L L L / 

S Ribes indecorum white flowering currant L L L L L / 

S Ribes malvaceum chaparral currant VL VL VL L / / 

S Ribes sanguineum red flowering currant L L L M / / 

S Ribes speciosum fuchsia flowering gooseberry L L L M / / 

S Ribes thacherianum Santa Cruz Island gooseberry / ? M ? ? ? 

S Gc Ribes viburnifolium evergreen currant L L L M / / 

T Robinia X ambigua locust L L L L M M 

T Robinia pseudoacacia black locust L L L L L L L 

P Rodgersia aesculifolia rogersia (aesculifolia) M ? ? ? ? ? 

P Rodgersia pinnata rogersia (pinnata) M ? ? ? ? ? 

P Rohdea japonica rohdea L M M M ? ? 

S P Romneya coulteri Matilija poppy VL VL VL L / / 

V Rosa banksiae Lady Banks rose L L M M M M 

S Rosa californica California wild rose L L L L / / 

91




V Rosa 'Cecile Brunner' Cecile Brunner rose L L M M M M 

S Rosa hybrids..bush rose M M M M H H 

V Rosa hybrids..climbing climbing roses M M M M H H 

S Rosa minutifolia Baja California wild rose L ? L ? M ? 

S Rosa rugosa Japanese rose L M M ? M M 

S Rosa woodsii var. ultramontana mountain wood rose M ? ? ? M ? 

P Roscoea purpurea roscoea M ? ? ? ? ? 

S P Rosmarinus officinalis rosemary L L L L M M 

P Gc Rosemarinus 'Prostratus' trailing rosemary L L L L M M 

S Rubus lineatus bramble (lineatus) M ? ? ? ? ? 

S Rubus pentalobus (calcynioides) bramble M M M / / / 

S Rubus ursinus California blackberry L L M ? ? ? 

P Rudbeckia spp. coneflower M M M M ? ? 

S Ruellia X brittoniana dwarf ruellia M ? L ? M L 

S Ruellia californica rama parda ? ? VL VL / L 

S Ruellia macrantha Christmas pride M / M ? ? ? 

S Ruellia peninsularis Baja ruellia / ? M M / M 

P Rumohra adiantiformis leather leaf fern M M M M / / 

P Ruscus spp. butcher's broom L L L ? ? ? 

T Sabal spp. palmetto / / M M / / 

Gc P Sagina subulata Irish moss M M M H H H 

Gc P Sagina subulata 'Aurea' Scotch moss M M M H H H 

T S Salix spp. willow H H H H H H 

S Salvia apiana white sage VL L VL VL L L 

S Salvia argentea silver sage L L L L ? ? 

P Salvia azurea grandiflora prairie sage M M L ? ? ? 

P Salvia 'Bee's Bliss' bee's bliss sage L ? L ? L ? 

P Salvia blepharophylla eyelash-leafed sage M ? M ? ? ? 

P Salvia buchananii Buchanan's sage M ? M M ? ? 

P Salvia cacaliaefolia Guatemalan blue sage M ? M M ? ? 

P Salvia californica Baja California sage / ? VL VL ? ? 

P Salvia chamaedryoides blue sage L L L L M M 

P Salvia chiapensis Chiapas sage M ? M M ? ? 

S Salvia clevelandii & hybrids Cleveland/Alan Chickering etc. L L VL L L L 

S P Salvia coahuilensis Coahuila sage L ? L ? ? ? 

P Salvia coccinea Texas sage L M M M M M 

P S Salvia confertiflora spike sage M ? M ? ? ? 

S Salvia 'Costa Rica Blue' Costa Rica blue sage M ? M ? ? ? 

P Salvia 'Dara's Choice' Sonoma sage L L L L L L 

P S Salvia darcyi Darcy sage M ? ? ? ? ? 

P Salvia discolor Andean silver leaf sage M / ? ? ? ? 

P Salvia dorisiana grapefruit-scented sage M ? M ? ? ? 

P Salvia dorrii purple sage / M L ? L L 

P S Salvia elegans pineapple sage M M M M ? ? 

P Salvia farinacea nealy cup sage M M M M / M 

P Salvia 'Firescape' Firescape sage ? ? ? ? ? ? 

P Salvia forskaohlei (hians) sage (forskaohlei/hians) M ? ? ? ? ? 

P S Salvia fulgens Mexican cardinal sage M ? M ? ? ? 

P S Salvia gesneriflora scarlet sage M ? M ? ? ? 

P Salvia glechomaefolia sage (glechomaefolia) M ? ? ? ? ? 

Salvia grahamii (See S. microphylla) 

S Salvia greggii & hybrids autumn sage L L L L M M 

P S Salvia guarantica anise scented sage M / ? ? ? ? 

Salvia hians (See S. forskaohlei) 

P S Salvia involucrata roseleaf sage M ? M ? ? ? 

S Salvia iodantha sage (iodantha) M ? M ? ? ? 

S Salvia X jamensis cvs. sage (jamensis cvs.) L ? ? ? ? ? 

S Salvia karwinskii Karwinski's sage M ? ? ? ? ? 

P Salvia koyamae maniko M ? ? ? ? ? 

S P Salvia leucantha Mexican bush sage L L L L / M 

S Salvia leucophylla purple sage L / L L / M 

92




P S Salvia madrensis forsythia sage M ? ? ? ? ? 

P Salvia 'Maraschino' maraschino sage M ? M ? ? ? 

P Salvia 'Mrs. Beard' Mrs. Beard sage ? ? M ? ? ? 

S Salvia mellifera black/green sage L L L L / M 

S Salvia mexicana Mexican sage M / M ? ? ? 

S Salvia microphylla cherry/Graham sage ? M L M L L 

P S Salvia muelleri royal purple autumn sage L M L ? M M 

Salvia muirii ? ? ? ? ? ? 

S Salvia munzii San Miguel Mountain sage L ? VL L L / 

P S Salvia officinalis garden/kitchen sage L M M M M M 

P Salvia patens gentian sage M M M ? ? ? 

P Salvia pratensis haematodes medow sage M M ? ? ? ? 

S Salvia penstemonoides big red sage M ? ? ? ? ? 

S Salvia 'Purple Majesty' purple magesty sage M M M ? ? ? 

S Salvia regla mountain sage L ? M ? ? ? 

P Salvia reptans sage (reptans) L ? ? ? ? ? 

P Salvia roemeriana cedar sage M ? ? ? ? ? 

P Salvia sinaloensis Sinaloan blue sage M ? M ? ? ? 

P Salvia sonomensis creeping/Sonoma sage L ? ? ? ? ? 

P S Salvia spathacea hummingbird/pitcher sage L ? L ? ? ? 

P Salvia X superba hybrids & cvs. sage (superba) M M M ? ? ? 

P Salvia thymoides blue salvia L ? L ? ? ? 

P Salvia uliginosa bog sage M M M ? / / 

P Salvia verticillata 'Purple Rain' purple rain sage M ? ? M ? ? 

P S Salvia 'Waverly' Waverly sage M ? M ? ? ? 

T S Sambucus spp. elderberry L L L L M M 

S P Santolina spp. lavender cotton L L L L L L 

T Sapium sebiferum Chinese tallow tree M M M M / / L 

Gc P Saponaria ocymoides rock soapwort L L M M / / 

S Sarcococca confusa sweet box L M M ? / / 

S Gc Sarcococca hookerana humilis sweet sarcococca L M M M / / 

S Sarcococca ruscifolia fragrant sarcococca L M M M / / 

S Sasa spp. bamboo (Sasa) L L M M / M 

S Gc Sasaella masamuniana albostriata white striped dwarf bamboo M ? M ? ? ? 

P Satureja chandleri San Miguel savory L ? ? ? ? ? 

P Satureja douglasii yerba buena L ? M ? ? ? 

P Satureja mexicana savory L ? ? ? ? ? 

P Saxifraga spp. saxifrage M M M H H H 

P Scabiosa spp. pincushion flower M M M M M M 

Gc P Scaevola aemula 'Diamond Head' blue wonder L L M M / / 

Gc P Scaevola 'Mauve Clusters' fan flower L L M M / / 

S Schlefflera actinophylla (Brassaia) Queensland umbrella tree / / M / / M 

S Schefflera arboricola Hawaiian elf schefflera / / H H / H 

S Schefflera elegantissima (Dizygotheca) thread leaf false aralia M M M M / M 

T S Schefflera pueckleri (Tupidanthus) Australian umbrella tree / / M H / H 

T Schinus molle California pepper tree VL L VL L M M L 

T Schinus polygamous Peruvian pepper tree VL L L L L M 

T Schinus terebinthefolius Brazilian pepper tree M M M M / M L 

P Schizostylis coccinia Kaffir lily M M M M / M 

P Schoenoplectus lacustris 

zebra rush M ? H H ? ? 

var.tabernaemontani 

T Schotia latifolia forest Boer bloom ? ? M ? ? ? 

T Sciadopitys verticillata Japanese umbrella pine M ? M / / / 

P Scilla hughii bluebell VL VL ? ? ? ? 

P Scilla peruviana Peruvian lily VL VL M M ? ? 

Scirpus cernuus (See Isolepis cernua) 

P Gc Sedum spp. stone crop L L L L L L 

P Selliera radicans swamp weed M ? M ? ? ? 

P Semiaquilegia ecalcarata semiaquilegia H ? M ? ? ? 

93




P S Semiarundinaria fastuosa Narihira bamboo M ? M M ? M 

P Sempervivum spp. house leek L L L L / L 

P Senecio cineraria dusty miller L L L L / M 

Senecio confusus (See Pseudogynoxys 

chenopodiodes) 

S Senecio flaccidus var. douglasii bush groundsel VL ? L L / M 

Senecio greyi (See Brachyglottis greyi) 

Gc Senecio mandraliscae kleinia / / L M / M 

S Senna australis (Cassia australis) Australian senna/cassia 

S Senna artemesioides (Cassia feathery cassia/senna L L L L L L 

artemesioides) 

S Senna bicapsularis (Cassia 

New Zealand cassia/senna L L L / / L 

candolleana) 

S Senna didymobotrya (Cassia 

senna/cassia didymobotrya ? ? L ? ? ? 

didymobotrya) 

S Senna lindheimeriana (Cassia Lindheim's senna/cassia 

lindheimeriana) 

S Senna multiglandulosa (Cassia wooly senna VL / L ? / M 

tomentosa) 

S Senna odorata (Cassia odorata) senna/cassia (odorata) ? ? L L / L 

S Senna polyantha (Cassia goldmanii) Goldman's senna/cassia ? ? L ? ? ? 

S Senna phyllodenia (Cassia phyllodenia) silver cassia/senna ? ? L L L L 

S Senna spectabilis (Cassia excelsa) senna/cassia (spectabilis/excelsa) ? ? L L ? ? 

S Senna splendida (Cassia splendida) golden wonder ? ? L ? ? ? 

S Senna sturtii (Cassia sturtii) Sturt's cassia/senna / / L L L L 

T Sequoia sempervirens coast redwood H H H H / / 

T Sequoiadendron giganteum giant sequoia M M / M / / 

S Serissa foetida serissa M / M M ? ? 

P Sesleria spp. moor grass M ? M ? / / 

P Setaria palmifolia palm grass H ? M M ? ? L 

P Setcreasea pallida 'Purple Heart' purple heart setcreasea / / M M H H 

S Shepherdia argentea silver buffaloberry L ? VL VL ? ? 

P Gc Shibatea kumasasa Okame-Zaza bamboo M ? M ? ? ? 

P Sidalcea spp. false mallow M M M ? ? ? 

P Sideritis syriaca sideritis L ? ? ? ? 

P Silene spp. moss pink/campion M M L L ? M 

S Simmondsia chinensis jojoba VL VL VL VL L L 

S Sinarundinaria nitida (Fargesia nitida) blue fountain bamboo M ? ? ? ? ? 

P Sinningia tubiflora velvet slipper L ? ? ? 

P Sisyrinchium bellum blue-eyed grass VL VL L L M M 

P Sisyrinchium californicum golden-eyed grass M M M M M M 

P Sisyrinchium convolutum sisysrinchium (convolutum) H ? ? ? ? ? 

P Sisysrinchium striatum sisysrinchium (striatum) M ? M ? / / 

S Skimmia japonica Japanese skimmia M M / / / / 

S Skimmia reevesiana Reeves skimmia ? ? / / / / 

V Solandra maxima cup of gold vine M M M M / / 

S Solanum aviculaare kangaroo apple L ? ? ? ? ? 

V S Solanum crispum Chilean potato tree M ? ? ? ? ? 

V Solanum jasminoides potato vine M M M M / M 

V Solanum wendlandii Costa Rican nightshade L / M / / M 

V Solanum xantii purple nightshade L L L L / L 

Gc P Soleirolia soleirolii baby's tears H H H H / H 

S Gc Sollya heterophylla Australian bluebell creeper L L L L / / 

V Sollya parvifolia vining bluebell ? ? ? ? ? ? 

T Sophora japonica Japanese pagoda tree L L M M M M 

T S Sophora secundiflora Texas mountain laurel L L L L M M 

T Sorbus aucuparia European mountain ash / M / / M / 

94




T Sorbus hupehensis mountain ash ? ? / / ? / 

T Sparmannia africana African linden H / M ? / ? 

S Spartium junceum Spanish broom VL VL VL L VL / L 

P Spathiphyllum spp. spathiphyllum / / H / / / 

T Spathodea campanulata African tulip tree / / M / / / 

P Sphaeralcea spp. desert/globe mallow L L L L / L 

S Spiraea spp. spiraea M M M M M M 

P Sporobolus airoides alkalai dropseed L ? ? ? ? L 

P Sprekelia formosissima Aztec lily L L L L L L 

P Stachys albotomentosa betony ? ? L ? ? ? 

P Stachys byzantina lamb's ears L L M M / M 

T Stenocarpus sinuatus firewheel tree / / M M / / 

P Stenocereus thurberi (Lemaireocereus) organ pipe cactus / / VL L / L 

P Stenomesson variegatum stenomesson M ? ? ? ? ? 

V Stephanotis floribunda Madagascar jasmine / / M M / M 

T Stewartia pseudocamellia Japanese stewartia M / / / / / 

V Stigmaphyllon ciliatum butterfly vine M / M ? ? ? 

P Stipa cernua nodding feather grass VL ? L L L L 

P Stipa gigantea giant needle grass M ? L L L L 

P Stipa lepida foothill stipa VL VL L L L L 

P Stipa pulchra feather grass VL L VL L L L 

P Stipa stipa spinosa desert bunch grass ? ? L L L L 

P Stipa tenuissima Mexican feather grass L ? L L L L 

P Stokesia laevis stokes aster M M M M M M 

T Strelitzia nicolai giant bird of paradise M / M M / M 

S Strelitzia reginae bird of paradise M M M M / M 

S Streptosolen jamesonii marmalade bush / / M H / / 

T Styrax japonicum Japanese snowbell M M / / M / 

S Styrax officinale californicum California storax L L L L M / 

S Styrax officinale redivivus snowdrop bush L L / ? ? / 

P S Sutera spp. sutera M ? L ? ? ? 

S Swainsonia galegifolia winter sweet pea M ? ? ? ? ? 

T Syagrus romanzoffiana queen palm L M M M M M 

S Symphoricarpus albus snowberry L L L L ? / 

S Symphoricarpus orbiculatus coralberry M ? ? ? ? / 

S Symphoricarpus mollis creeping snowberry L L ? ? ? / 

S Symphyandra spp. ring bellflower M ? M ? ? ? 

S Syringa X chinensis Chinese lilac M M / ? ? / 

S Syringa X hyacinthiflora Canadian lilac M M / ? ? / 

S Syringa patula Korean lilac M M / ? ? / 

S Syringa X persica Persian lilac L L / ? M / 

S Syringa vulgaris lilac L L / M M / 

S Syzygium paniculatum Australian brush cherry M M M M / / 

S Syzygium smithii Smith's brush cherry ? ? M M / ? 

S Tabebuia chrysotricha golden trumpet tree ? / M M / M 

T Tabebuia impetiginosa (ipe) pink/lavender trumpet tree / / M M / / 

T Tagetes lemmoni mountain marigold L L L L M M 

S P Tagetes lucida Mexican tarragon M M M M M M 

P Talinium calcynium flame flower L ? ? ? ? ? 

P Tamarix spp. tamarisk VL VL L L L L L L 

T S Tanacetum coccinium (Pyrethrum painted daisy M / L ? ? ? 

roseum) 

P Tanacetum haradjanii tansy L ? L ? ? ? 

Tanacetum herderi (See Hippolyta 

herderi) 

P Tanacetum parthenium 

feverfew L L M M M M 

(Chrysanthemum parthenium) 

T Taxodium distichum bald cypress M M M M / / 

T Taxodium mucronatum Montezuma cypress M M M M / / 

T S Taxus baccata English yew M M M M M / 

95




T S Taxus baccata 'Fastigiata' Irish yew M M M M M / 

S Taxus cuspidata Japanese yew M ? M ? ? ? 

S Taxus 'Meyeri' Meyer's Yew M ? ? ? ? ? 

S Taxus X media cvs. Yew (media cvs.) M ? M ? ? ? 

S Tecoma 'Orange Jubilee' orange jubilee tecoma M M ? ? / M 

S T Tecoma X smithii Smith's tecoma ? ? M ? ? ? 

T S Tecoma stans yellow bells / / L L / L 

V Tecomanthe speciosa tecomanthe M ? ? ? ? ? 

S V Tecomaria capensis cape honeysuckle M M M M / M 

P Tellima grandiflora fringe cups M ? ? ? ? ? 

P Telopea speciosissima waratah M / ? ? ? ? 

S Ternstroemia gymnanthera Japanese ternstroemia M M M M M / 

S Tetraneuris acaulis (Hymenoxis acaulis) sweet shade ? ? ? ? / M 

S Tephrosia grandiflora hoary pea M ? ? ? ? ? 

V Tetrapanax papyrifer rice paper plant L M M M / M 

Gc Tetrastigma voinieranum Javan grape / / M M / M 

P Gc Teucrium chamaedrys germander L L L L M M 

S Gc Teucrium cossonii Majorcan germander VL L L L / L 

S Teucrium fruticans bush germander L L L L / M 

P Teucrium hyrcanicum germander (hyrcanicum) L ? ? ? ? ? 

S Teucrium marum cat thyme L L L L ? ? 

P S Teucrium scorodonia 'Crispum' germander (crispum) M ? M ? ? ? 

P Thalictrum aquilegifolium purple meadow rue H ? M ? ? ? 

P Thalictrum coreanum meadow rue (coreanum) M ? ? ? ? ? 

P Thalictrum delavayi lavender shower H ? M M ? ? 

P Thalictrum fendleri var. polycarpum meadow rue M ? L L ? ? 

P Thalictrum flavum spp glaucum meadow rue (flavum) H ? M ? ? ? 

P Thalictrum dipterocarpum (See T. 

H ? ? ? ? ? 

delavayi) 

P Thalictrum polycarpum medow rue M ? M M M M 

P Thalictrum rochenbrunianum lavender mist H ? ? ? ? ? 

Thalictrum speiosissimum (See T. 

flavum spp glaucum) 

P Thamnocalamus spathaceus (Fargesia umbrella bamboo M ? M M ? ? 

murieliae) 

T S Thevetia peruviana yellow oleander / / M M / M 

T Thevetia thevetioides giant thevetia / / M M / M 

S Thuja occidentalis American arborvitae M M M M M M 

S Thuja orientalis (See Platycadus 

orientalis) 

V Thunbergia alata black eyed susan M M M M M M 

V Thunbergia battiscombei thunbergia (battiscombei) M ? M M M M 

V Thunbergia grandiflora sky flower M / M / / M 

V Thunbergia gregorii orange clock vine M / M M / M 

V Thunbergia mysorensis thumbergia (mysorensis) M ? M / / / 

GC P Thymus spp. thyme M M M M M M 

P Thysanolaena maxima tiger grass ? ? M M ? ? 

S Tiarella wherryi sugar scoop M / M ? M ? 

S Tibuchina heteromalla glory bush M / M ? / / 

S Tibuchina urvilleana (semidecandra) princess flower M / M H / H 

T Tilia americana American linden M M / / / / 

T Tilia cordata little leaf linden M M / / / / 

T Tipuana tipu tipu tree M / M M / / 

P Todea barbara crepe fern M ? M ? ? ? 

T Toona sinensis (Cedrela sinensis) Chinese toon ? ? L ? ? ? 

P Trachelium caeruleum throatwart M ? M ? ? ? 

Gc V Trachelospermum asiaticum Asian star jasmine M M M M M M 

S Gc Trachelospermum jasminoides star jasmine M M M M M M 

T Trachycarpus fortunei windmill palm L M M M / M 

T Trachycarpus takil takil fan palm ? / M M / M 

96




P Tradescantia X andersoniana spiderwort M M M M M M 

P Tradescantia fluminensis wandering Jew M / M ? ? ? 

P Tradescantia pallida spiderwort M ? M ? ? ? 

Trichocereus spp. (See Echinopsis spp.) 

S P Trichostema lanatum woolly/mountain blue curls VL VL VL L / M 

Trichostema parishii (See T. lanatum) / 

P Tricyrtis hirta toad lily M ? L ? ? ? 

Gc Trifolium fragiferum O'Connor O'Connors legume (landscape M M M M M M 

use) 

Gc Trifolium fragiferum O'Connor O'Conners legume (revegetation L L L L L L 

use) 

Gc Trifolium repens white clover M / H H ? ? 

Tristania conferta (See Lophostemon 

confertus) 

Tristania laurina (See Tristaniopsis 

laurina) 

T Tristaniopsis laurina little leaf myrtle M / M M / / 

P Tritelia laxa Ithuriel's spear Vl VL L L ? ? 

P Tritonia spp. tritonia 

S Trixis californica trixis ? ? ? ? L M 

P Trollius spp. globeflower H H M M H H 

P Tropaeolum majus nasturtium M M / M / M L 

T Tsuga canadensis Canadian hemlock M / / / / / 

P Tulbaghia fragrans sweet garlic M M M M / M 

P Tulbaghia violacea society garlic M M M M / M 

Tupidanthus calyptratus (See Schefflera 

pueckleri) 

P Tweedia caesulea (Oxypetalum blue flowered milkweed M ? M ? ? ? 

caeruleum) 

S Ugni molinae Chilean guava M M M M ? ? 

S T Ungnadia speciosa Mexican buckeye ? ? ? ? L M 

T Ulmus americana American elm M M M M ? / 

T Ulmus glabra Scotch elm M ? ? ? ? ? 

T Ulmus parvifolia Chinese evergreen elm M M M M M M 

T Ulmus pumila Siberian elm L L / L M M 

T Umbellularia californica California bay M M M M / / 

P Urginea maritima sea squill L ? L ? / / 

S Vaccinium moupinense Himalayan blueberry M ? ? ? / / 

S Vaccinium ovatum evergreen huckleberry M M / / / / 

S Vaccinium parvifolium red huckleberry M M / / / / 

S Vaccinium vitis-idaea foxberry M ? / / / / 

P Gc Vancouveria spp. inside-out flower M ? ? ? ? ? 

S Vauquelinia californica Arizona rosewood L ? / / M M 

S Vauquelinia corymbosa var. heterodon narrow leaf rosewood ? ? / / ? L 

P Velthemia bracteata forest lily L ? M / ? ? 

P Verbascum bombiciferum mullein M ? L ? ? ? 

P Verbascum phoeniceum purple mullein L L L L / / 

P Verbena bonariensis verbena (bonariensis) VL M L L M M 

Gc P Verbena gooddingii Goodding verbena L L L L / M 

P Verbena hybrids garden verbena L L M M / M 

Gc P Verbena lilacina lilac verbena L ? L L / L 

Gc Verbena peruviana Peruvian verbena L L L L / M 

Gc P Verbena rigida vervian M M M M / M 

Gc Verbena stricta hoary vervian L M M M M M 

Gc Verbena tenera (pulchella) rock verbena M ? ? M M M 

Gc Verbena tenuisecta moss verbena L L L L / M 

P Veronica spp. veronica M M M / / M 

Gc Veronica repens speedwell M M M / / / 

97




P Veronicastrum virginicum blackroot M ? ? ? ? ? 

S Viburnum 'Anne Russel' Anne Russel viburnum M ? ? ? ? ? 

S Viburnum awabuki awabuki viburnum M ? M ? ? ? 

S Viburnum X bodnantense Bodnant viburnum M ? ? ? ? ? 

S Viburnum X burkwoodii Burkwood viburnum L M M / M / 

S Viburnum carlesii Korean spice viburnum M ? ? ? ? ? 

S Viburnum carlesii cvs. Cayuga,Chesapeake, Eskimo M ? ? ? ? ? 

Viburnum 

S Viburnum davidii David viburnum M M / / / / 

S Viburnum japonicum Japanese viburnum M M M M M / 

S Viburnum 'Mohawk' Mohawk viburnum M ? ? ? ? ? 

S Viburnum odoratissimum sweet viburnum L M M / M / 

S Viburnum opulus European cranberry bush L M M M M / 

S Viburnum plicatum tomentosum doublefile viburnum M M M M ? / 

S Viburnum X pragense Prague viburnum ? ? ? ? ? ? 

S Viburnum X rhytidophylloides viburnum (rhytidophylloides) M ? ? ? ? ? 

S Viburnum rhytidophyllum leatherleaf viburnum M M M M M M 

S Viburnum setigerum tea viburnum ? ? M ? ? ? 

S Viburnum suspensum sandanqua viburnum M M M M M M 

S Viburnum tinus laurustinus M M M M M M 

S Viburnum trilobum American cranberry M ? ? ? ? ? 

V Vigna caracalla snail vine M / M M / M 

S Viguiera deltoidea goldeneye / ? ? ? L L 

S Viguiera laciniata San Diego County viguiera / ? VL ? ? ? 

T Villebrunea pedunculata villebrunea ? ? M ? ? ? 

Gc Vinca major periwinkle M M M M M M L 

Gc Vinca minor periwinkle M M M M M M 

P Viola adunca western dog violet M ? M ? ? ? 

P Viola cornuta horned violet M ? M ? ? ? 

P Gc Viola hederacea Australian violet M M M H M M 

P Viola japonica violet (japonica) M ? ? ? ? ? 

P Gc Viola labradorica Labrador violet M M M H H H 

P Gc Viola odorata sweet violet M M M H H H 

P Viola sempervirens redwood violet L ? ? ? ? ? 

T Vitex agnus-castus chaste tree L L L M M M 

V Vitis californica California wild grape L M VL L M M 

V Vitis girdiana desert grape L M L L M M 

V Vitis labrusca American grape L L M M M M 

V Vitis vinifera European grape L L M M M M 

P Wachendorfia thrysiflora red root H ? ? ? ? ? 

P Wahlenbergia gloriosa royal bluebell M ? ? ? ? ? 

T Washingtonia filifera California fan palm L M L L M M 

T Washingtonia robusta Mexican fan palm L M L L M M 

P Watsonia spp. watsonia L M L M M M L 

P Gc Wedelia trilobata trailing daisy ? ? H / / ? 

S Weigela coraeensis white weigela ? ? M ? ? ? 

S Weigela florida weigelia M M M M M / 

S Westringia fruiticosa (rosmariniformis) coast rosemary L L L L / M 

S Westringia glabra violet westringia L ? L ? / M 

S Westringia longifolia westringia (longifolia) L ? L ? / M 

S Westringia raleighi Raleigh westringia L ? L ? / M 

S Westringia 'Wynyabbie Gem' Wynyabbie gem westringia L ? L ? / M 

V Wisteria spp. wisteria M M M M M M 

P Woodwardia fimbriata giant chain fern M M M M / / 

P Woodwardia radicans European chain fern H / H H H H 

P Xanthorrhoea spp. grass tree L / L L ? ? 

P Xeronema calistemon poor knight's lily M ? ? ? ? ? 

P Xerophyllum tenax bear grass L ? ? ? ? ? 

S P Xylococcus bicolor mission manzanita ? ? VL L M / 

S Xylosma congestum shiny xylosma L L M M M M 

S T Yucca spp. yucca L L L L L L 

98




P Zaluzianskya katherinae zaluzinskya M ? ? ? ? ? 

S Zamia pumila Florida arrowroot / / M H / / 

P Zantedeschia aethiopia calla lily M M M M / M L 

P Zantedeschia spp. & hybrids pink/yellow calla lily M M M M / M 

P Zauschneria spp. (see Epilobium) 

T Zelkova serrata saw leaf zelkova M M L M M M 

P Zephryranthes spp. zephyr flower M M M M / M 

Zephryanthes robusta (See Habranthus 

robustus) 

P Zexmenia hispida zexmenia ? ? ? ? ? ? 

GC P Zinnia grandiflora prairie zinnia M M M M M M 

T Ziziphus jujuba Chinese jujube L L L M M M 

T Ziziphus obtusifolia graythorn / ? ? ? ? ? 

Gc P Zoyzia tenuifolia Mascarene grass M M M M M M 

99

Common Names Index 

COMMON NAME 

Aaron's beard 

Abyssinian acacia 

Abyssinian banana 

African boxwood 

African corn lily 

African daisy 

African daisy 

African fern pine 

African linden 

African plumbago 

African sumac 

African tulip tree 

agapetes (serpens) 

agave 

Alaskan fern 

Albany bottlebrush 

Alberta spruce 

Albury purple hypericum 

alectryon/titoki 

Aleppo pine 

Algerian ivy 

'Alice Dupont' etc. 

alkalai dropseed 

allium 

almond 

aloe 

aloysia 

alpine campion 

alpine geranium 

alpine totara 

alpine water fern 

alum root 

amaryllis 

American arborvitae 

American cranberry 

American elm 

American grape 

American linden 

American smoke tree 

amur maple 

Andean silver leaf sage 

angel flower 

angel wing jasmine 

angel's trumpet 

anise scented sage 

Anne Russel viburnum 

Apache plume 

apple 

apricot 

Arabian jasmine 

Argentine mesquite 

Arizona ash 

Arizona mesquite 

Arizona rosewood 

Arizona sycamore 

Arizona walnut 

BOTANICAL NAME 

Hypericum calycinum 

Acacia abyssinica 

Ensete ventricosum 

Myrsine africana 

Ixia spp. 

Arctotis hybrids 

Osteospermum spp. 

Afrocarpus gracilior (Podocarpus gracilior) 

Sparmannia africana 

Ceratostigma abyssinicum 

Rhus lancea 

Spathodea campanulata 

Agapetes serpens (Pentapetpterygium) 

Agave spp. 

Polystichum X setigerum 

Callistemon speciosus 

Picea glauca 

Hypericum X inodorum 'Albury Purple' 

Alectryon excelsus 

Pinus halepensis 

Hedera canariensis 

Mandevilla cvs. 

Sporobolus airoides 

Allium spp. 

Prunus spp. (edible) 

Aloe spp. 

Aloysia machrostachya 

Lychnis alpina 

Erodium reichardii 

Podocarpus nivalis 

Blechnum penna-marina 

Heuchera micrantha 

Hippeastrum spp. 

Thuja occidentalis 

Viburnum trilobum 

Ulmus americana 

Vitis labrusca 

Tilia americana 

Cotinus obvatus 

Acer tataricum ssp. ginnala 

Salvia discolor 

Angelonia angustifolia 

Jasminum nitidum 

Brugmansia spp. 

Salvia guarantica 

Viburnum 'Anne Russel' 

Fallugia paradoxa 

Malus spp.(edible) 

Jasminum sambac 

Prosopis alba 

Fraxinus velutina 

Prosopis juliflora 

Vauquelinia californica 

Platanus wrightii 

Juglans major 

101


COMMON NAME 

arnica 

arrow bamboo 

arroyo lupin 

ash leaved gum, silver dollar tree 

ashy silktassel 

Asian bell flower 

Asian star jasmine 

Asphodel 

astelia 

aster 

athanasia 

Atlas cedar 

Australia fountain palm 

Australian agathis/ kauri 

Australian blue grass 

Australian bluebell creeper 

Australian brush cherry 

Australian fuchsia 

Australian heath 

Australian pea 

Australian senna/cassia 

Australian tea tree 

Australian tree fern 

Australian umbrella tree 

Australian violet 

Australian willow 

Austrian black pine 

autumn crocus 

autumn sage 

avens 

avocado 

awabuki viburnum 

azalea 

azara 

Aztec lily 

baboon flower 

baby bonnets 

baby's breath 

baby's breath 

baby's tears 

Bailey acacia 

Baja bush-snapdragon 

Baja California sage 

Baja California wild rose 

Baja evening primrose 

Baja fairy duster 

Baja indigo bush 

Baja ruellia 

bald cypress 

balloon flower 

balsam/balm of Gilead poplar 

bamboo 

bamboo 

bamboo (Bambusa) 

bamboo (Phylostachys) 

bamboo (Sasa) 


Arnica montana 

Pseudosasa japonica 

Lupinus sparsiflorus 

Eucalyptus cinerea 

Garrya flavescens 

Radermachera sinica 

Trachelospermum asiaticum 

Asphodeline taurica 

Astelia nivicola 

Aster spp. 

Athanasia acerosa 

Cedrus atlantica 

Livistona australis 

Agathis australis 

Poa costineata 

Sollya heterophylla 

Syzygium paniculatum 

Correa spp. 

Epacris gunii 

Dipogon lignosus 

Senna australis (Cassia australis) 

Leptospermum laevigatum 

Cyathea cooperii 

Schefflera pueckleri (Tupidanthus) 

Viola hederacea 

Geijera parviflora 

Pinus nigra 

Colchicum agrippium 

Salvia greggii & hybrids 

Geum spp. 

Persea americana 

Viburnum awabuki 

Rhododendron spp. 

Azara integrifolia 

Sprekelia formosissima 

Babiana stricta hybrids 

Coursetia axillaris 

Gypsophila cerastioides 

Gypsophila paniculata 

Soleirolia soleirolii 

Acacia baileyana 

Galvesia juncea 

Salvia californica 

Rosa minutifolia 

Oenothera stubbei 

Calliandra californica 

Dalea orcutii 

Ruellia peninsularis 

Taxodium distichum 

Platycodon grandiflorus 

Populus balsamifera 

Chusquea coronalis 

Drepanostachyum hookerianum 

Bambusa spp. 

Phyllostachys spp. 

Sasa spp. 

102


COMMON NAME 

bamboo muhly 

banana 

banana-leaf fig 

banana shrub 

barberry 

barberry 

barleria 

barrel cactus 

barrel cactus 

bat-faced cuphea 

baumea 

bayberry 

beach aster 

beach evening primrose 

beach pine 

bear grass 

bear grass 

bearded iris 

bear's breech 

beauty berry 

beauty berry 

beauty bush 

bee balm 

bee's bliss sage 

bell flower 

bell mallee 

bentennial baccharis 

betony 

big leaf maple 

big red sage 

Bigelow sneezeweed 

bird catcher tree 

bird of paradise 

bird's eye bush 

bird's foot fern 

bird's nest fern 

birdsfoot trefoil 

bishop pine 

bishop's hat 

bitter root 

black alder 

black box 

black bush 

black coral pea 

black cottonwood 

black dalea 

black eyed susan 

black locust 

black mondo grass 

black pennisetum 

black spruce 

black tea 

black/green sage 

blackfoot daisy 

blackroot 

blackwood acacia 


Muhlenbergia dumosa 

Musa spp. 

Ficus barteri 

Michelia figo 

Berberis spp. 

Berberis X stenophylla 'Irwinii' 

Barleria obtusa 

Echinocactus spp. 

Ferocactus spp. 

Cuphea llavea 

Baumea rubiginosa 

Myrica pennsylvanica 

Erigeron glaucus 

Camissonia cherianthifolia (Oenothera) 

Pinus contorta 

Nolina spp. 

Xerophyllum tenax 

Iris spp. 

Acanthus mollis 

Callicarpa bodinieri 

Callicarpa japonica 

Kolkwitzia amabalis 

Monarda didyma 

Salvia 'Bee's Bliss' 

Campanula spp. 

Eucalyptus preissiana 

Baccharis 'Centennial' 

Stachys albotomentosa 

Acer macrophyllum 

Salvia penstemonoides 

Helenium bigelovii 

Pisonia umbellifera 

Strelitzia reginae 

Ochna serrulata 

Pellaea mucronata 

Asplenium nidus 

Lotus corniculatus 

Pinus muricata 

Epimedium grandiflorum 

Lewisia cotyledon 

Alnus glutinosa 

Eucalyptus largiflorens 

Corethrogyne californica 

Kennedia nigricans 

Populus trichocarpa 

Dalea frutescens 

Thunbergia alata 

Robinia pseudoacacia 

Ophiopogon planiscapus var. nigrescens 

Pennisetum alopecuroides 

Picea mariana 

Melaleuca lanceolata 

Salvia mellifera 

Melampodium leucanthum 

Veronicastrum virginicum 

Acacia melanoxylon 

103


COMMON NAME 

bladder pod 

blanket flower 

bleeding heart 

blood red trumpet vine 

blue-eyed grass 

blue bamboo 

blue bird hydrangea 

blue boy/girl etc. cvs. 

blue cape pea 

blue dawn flower 

blue dracaena palm 

blue fescue 

blue flowered milkweed 

blue fountain bamboo 

blue ginger 

blue gramma 

blue gum 

blue hair grass 

blue hesper palm 

blue hibiscus 

blue leaf wattle 

blue marguerite 

blue mist 

blue oak 

blue oat grass 

blue palo verde 

blue pea 

blue sage 

blue salvia 

blue star creeper 

blue wonder 

bluebell 

blueberry 

blueberry creeper 

Bodnant viburnum 

bog rosemary 

bog sage 

bolleana poplar 

book-leaf mallee 

boronia 

Bosnian pine 

Boston fern 

Boston ivy 

bottle brush 

bottle palm 

bottle tree 

bougainvillea 

bower vine 

bower wattle 

Bowles mauve wallflower 

box-leaved holly 

box elder 

box honeysuckle 

box leaf azara 

boxthorn 

bracelet honey-myrtle 


Cleome isomeris 

Gaillardia grandiflora 

Dicentra spp. 

Distictis buccinatoria 

Sisyrinchium bellum 

Drepanostachyum falcatum (Arundinaria) 

Hydrangea serrata 

Ilex X meserveae 

Otholobium fruiticans 

Ipomea indica (acuminata0 

Cordyline indivisa 

Festuca glauca 

Tweedia caesulea (Oxypetalum caeruleum) 

Sinarundinaria nitida (Fargesia nitida) 

Dichorisandra thyrsifolia 

Bouteloua gracilis 

Eucalyptus globulus 

Koelaria glauca 

Brahea armata 

Alyogyne huegelii 

Acacia saligna 

Felicia amelloides 

Caryopteris X clandonensis 

Quercus douglasii 

Helictotrichon sempervirens 

Parkinsonia florida (Cercidium floridum) 

Psoralea pinnata 

Salvia chamaedryoides 

Salvia thymoides 

Laurentia fluviatilis 

Scaevola aemula 'Diamond Head' 

Scilla hughii 

Dianella tasmanica 

Ampelopis brevipedunculata 

Viburnum X bodnantense 

Andromeda polifolia 

Salvia uliginosa 

Populus alba 'Pyramidalis' 

Eucalyptus kruseana 

Boronia spp. 

Pinus heldreichii 

Nephrolepis exaltata 

Parthenocissus tricuspidata 

Callistemon citrinus 

Nolina recurvata (Beaucarnea recurvata) 

Brachychiton populneus 

Bougainvillea spp. 

Pandorea jasminoides 

Acacia cognata (A.subporosa) 

Erysimum 'Bowles Mauve' 

Ilex crenata 

Acer negundo 

Lonicera nitida 

Azara microphylla 

Lycium exertum 

Melaleuca armillaris 

104


COMMON NAME 

brake fern 

bramble 

bramble (lineatus) 

Brazilian butterfly tree 

Brazilian pepper tree 

Brazilian plume flower 

Brazilian sky flower 

breath of heaven 

bridal wreath 

bridal wreath 

bridal wreath 

Bridget bloom heucherella 

brightness lobelia 

Brisbane box 

brittle bush 

broad buckler fern 

brodiaea 

bronze loquat 

broom (Cytisus) 

broom (Genista) 

Buchanan's sage 

buckwheat 

bulb oat grass 

bulbinella 

bull grass 

bunchberry 

bunya-bunya 

Burford holly 

Burkwood daphne 

Burkwood viburnum 

Burmese plumbago 

burning bush 

burning bush/dittany 

bursera 

bush anemone 

bush germander 

bush groundsel 

bush mallow 

bush mallow 

bush morning glory 

bush poppy 

bushrue 

bushy clematis 

bushy yate 

butcher's broom 

buttercup 

butterfly bush 

butterfly bush 

butterfly vine 

butterfly weed 

button fern 

cadaga 

cajeput tree 

Calabrian pine 

calamint 

calico flower 


Pteris spp. 

Rubus pentalobus (calcynioides) 

Rubus lineatus 

Bauhinia forficata 

Schinus terebinthefolius 

Justicia carnea 

Duranta stenostachya 

Coleonema pulchrum 

Deutzia spp. 

Francoa ramosa 

Francoa sonchifolia 

X Heucherella tiarelloides 'Bridget Bloom' 

Lobelia 'Brightness' 

Lophostemon confertus 

Encelia farinosa 

Dryopteris dilatata 

Brodiaea spp. 

Eryobotrya deflexa 

Cytisus spp. 

Genista spp. 

Salvia buchananii 

Eriogonum spp. 

Arrhenatherum elatius ssp bulbosum 

Bulbinella robusta 

Muhlenbergia emersleyi 

Cornus canadensis 

Araucaria bidwilii 

Ilex cornuta 'Burfordii' 

Daphne X burkwoodii 

Viburnum X burkwoodii 

Ceratostigma griffithii 

Euonymous alatus 

Dictamnus spp. 

Bursera hindsiana 

Carpenteria californica 

Teucrium fruticans 

Senecio flaccidus var. douglasii 

Lavatera maritima 

Malacothamnus fasciculatus 

Convolvulus cneorum 

Dendromecon spp. 

Cneoridium dumosum 

Clematis integrifolia 

Eucalyptus lehmannii 

Ruscus spp. 

Ranunculus cortusaefolius 

Buddleja davidii 

Clerodendrum ugandense 

Stigmaphyllon ciliatum 

Asclepias tuberosa 

Pellaea rotundifolia 

Eucalyptus torelliana 

Melaleuca viridiflora var. rubiflora 

Pinus brutia 

Calamintha spp. 

Aristolochia elegans 

105


COMMON NAME 

California bay 

California black oak 

California black walnut 

California blackberry 

California buckeye 

California buttercup 

California Dutchman's pipe 

California encelia 

California fan palm 

California fescue 

California fuchsia 

California holly grape 

California juniper 

California lilac 

California pepper tree 

California poppy 

California privet 

California scrub oak 

California storax 

California sycamore 

California wild grape 

California wild rose 

calla lily 

Callery pear 

callistemon (subulatus) 

calyophus (drummondii) 

camellia 

camphor tree 

Canadian hemlock 

Canadian lilac 

canary-bird bush 

Canary island daisy 

Canary Island date palm 

Canary Island pine 

Canary Island rose 

cane bluestem 

cane reed 

canna 

canyon live oak 

cape chestnut 

cape fuchsia 

cape honeysuckle 

cape plumbago 

cape reed 

Cape reed 

cape tulip 

cape weed 

cape weed 

caper bush 

carob 

Carolina allspice 

Carolina jessamine 

Carolina laurel cherry 

Carolina poplar 

carpet bugle 

Carribean copper plant 


Umbellularia californica 

Quercus kelloggii 

Juglans hindsii 

Rubus ursinus 

Aesculus californica 

Ranunculus californicus 

Aristolochia californica 

Encelia californica 

Washingtonia filifera 

Festuca californica 

Epilobium spp.(Zauchneria) 

Mahonia pinnata & cvs. 

Juniperus californica 

Ceanothus spp. 

Schinus molle 

Eschscholzia californica 

Ligustrum ovalifolium 

Quercus berberidifolia 

Styrax officinale californicum 

Platanus racemosa 

Vitis californica 

Rosa californica 

Zantedeschia aethiopia 

Pyrus calleryana cultivars 

Callistemon subulatus 

Calyophus drummondii 

Camellia japonica 

Cinnamomum camphora 

Tsuga canadensis 

Syringa X hyacinthiflora 

Crotalaria agatiflora 

Nauplius sericeus (Asteriscus sericeus) 

Phoenix canariensis 

Pinus canariensis 

Aeonium spp. 

Bothriochloa barbinoides 

Arundinaria gigantea 

Canna spp. 

Quercus chrysolepis 

Calodendrum capense 

Phygelius X rectus 

Tecomaria capensis 

Plumbago auriculata (campense0 

Chondropetalum tectorum 

Elegia capensis 

Homeria spp. 

Arctotheca calendula 

Phyla nodiflora (Lippia nodiflora) 

Capparis spinosa 

Ceratonia siliqua 

Calycanthus floridus 

Gelsemium sempervirens 

Prunus caroliniana 

Populus X canadensis 

Ajuga reptans 

Euphorbia cotinifolia 

106


COMMON NAME 

carrotwood 

cascalote 

cashmere bouquet 

cast iron plant 

cat thyme 

Catalina cherry 

Catalina ironwood 

catclaw acacia 

catmint/catnip 

cat's claw 

cautleya 

Cayuga,Chesapeake, Eskimo Viburnum 

ceanothus 

Cecile Brunner rose 

cedar of Lebanon 

cedar sage 

centaurea (rupestris) 

central Australian fan palm 

chalk buckwheat 

chamaedorea 

chameleon houttuynia 

chamise 

chamomile 

chaparral currant 

chaparral honeysuckle 

chasmanthe 

chaste tree 

cheese bush 

chenile honey-myrtle 

cherimoya 

cherry 

cherry/Graham sage 

Chiapas sage 

Chilean guava 

Chilean jasmine 

Chilean mesquite 

Chilean potato tree 

Chilean wine palm 

chinaberry 

chincherinchee 

Chinese abelia 

Chinese dogwood 

Chinese evergreen elm 

Chinese evergreen wisteria 

Chinese fan palm 

Chinese flame tree 

Chinese flame tree 

Chinese fountain grass 

Chinese foxglove 

Chinese fringe tree 

Chinese hackberry 

Chinese hibiscus 

Chinese holly grape 

Chinese indigo 

Chinese jujube 

Chinese lilac 


Cupaniopsis anacardioides 

Caesalpinea cacalaco 

Clerodendrum bungei 

Aspidistra elatior 

Teucrium marum 

Prunus lyonii 

Lyonothamnus floribundus 

Acacia greggii 

Nepeta spp. 

Macfadyena unguis-cati 

Cautleya spicata 

Viburnum carlesii cvs. 

Ceanothus cultivars 

Rosa 'Cecile Brunner' 

Cedrus libani 

Salvia roemeriana 

Centaurea rupestris 

Livistona mariae 

Eriophyllum lanatum 

Chamaedorea spp. 

Houttuynia cordata 'Chameleon' 

Adenostoma fasciculatum 

Chamaemelum nobile 

Ribes malvaceum 

Lonicera subspicata 

Chasmanthe aethiopica 

Vitex agnus-castus 

Hymenoclea monogyra 

Melaleuca huegelii 

Annona cherimola 

Prunus spp. (edible) 

Salvia microphylla 

Salvia chiapensis 

Ugni molinae 

Mandevilla laxa 

Prosopis glandulosa 

Solanum crispum 

Jubaea chilensis 

Melia azedarach 

Ornithogalum thyrsoides 

Abelia chinensis 

Cornus kousa chinensis 

Ulmus parvifolia 

Milletia taiwanensis 

Livistona chinensis 

Koelreuteria bipinnata 

Koelreuteria elegans 

Pennisetum orientale 

Rehmannia elata 

Chionanthus retusus 

Celtis sinensis 

Hibiscus rosa-sinensis 

Mahonia lomariifolia 

Indigofer decora (incarnata) 

Ziziphus jujuba 

Syringa X chinensis 

107


COMMON NAME 

chinese mahonia 

Chinese maple 

Chinese photinia 

Chinese pieris 

Chinese pistache 

Chinese plumbago 

Chinese redbud 

Chinese strawberrry tree 

Chinese tallow tree 

Chinese toon 

chinquapin oak 

chir pine 

chitalpa 

chocolate cosmos 

chocolate scented daisy 

Christmas pride 

Christmas/Lenten rose 

chuparosa 

cider gum 

cigar plant 

cinnamon fern 

cinquefoil 

Clanwilliam daisy 

Clark lily turf 

clay wattle 

Cleveland/Alan Chickering etc. 

cliff date palm 

cliff rose 

climbing hydrangea 

climbing roses 

climbing snapdragon 

cluster pine 

clustered fishtail palm 

Coahuila sage 

Coahuilan hesperaloe 

coast beefwood 

coast live oak 

coast redwood 

coast rosemary 

coast silktassel 

coastal bush lupine 

coastal statice 

cockspur coral tree 

coffeeberry 

Colorado spruce 

columbia lewisia 

columbine 

combretum 

common bluebeard 

common guava 

common hackberry 

common heliotrope 

common jasmine 

common witch hazel 

common yarrow 

cone flower 


Mahonia fortunei 

Acer truncatum 

Photinia serratifolia (P. serrulata) 

Pieris formosa var.forestii 

Pistacia chinensis 

Ceratostigma willmottianum 

Cercis chinensis 

Myrica rubra 

Sapium sebiferum 

Toona sinensis (Cedrela sinensis) 

Quercus muhlenbergii 

Pinus roxburghii 

X Chitalpa tashkentensis 

Cosmos atrosanguineus 

Berlandiera lyrata 

Ruellia macrantha 

Helleborus spp. 

Justicia californica 

Eucalyptus gunnii 

Cuphea ignea 

Osmunda cinnamomea 

Potentilla fruticosa cvs. 

Euryops speciosissimus 

Ophiopogon clarkii 

Acacia glaucoptera 

Salvia clevelandii & hybrids 

Phoenix rupicola 

Cowania mexicana 

Hydrangea anomala petiolaris 

Rosa hybrids..climbing 

Asarina barclaiana (Maurandya) 

Pinus pinaster 

Caryota mitis 

Salvia coahuilensis 

Hesperaloe funifera 

Allocasuarina verticillata (Casuarina stricta) 

Quercus agrifolia 

Sequoia sempervirens 

Westringia fruiticosa (rosmariniformis) 

Garrya eliptica 

Lupinus arboreus 

Limonium commune var. californicum 

Erythrina crista-galli 

Rhamnus californicus 

Picea pungens 

Lewisia columbiana rupicola 

Aquilegia spp. 

Combretum fruticosum 

Caryopteris incana 

Psidium guajava 

Celtis occidentalis 

Heliotropum arborescens 

Jasminum officinale f. grandiflorum 

Hamamelis virginiana 

Achillea millefolium & hybrids 

Echinacea spp. 

108


COMMON NAME 

coneflower 

confederate rose 

coolibah 

copper false chestnut 

coral bells 

coral gum 

coral plant 

coral poker 

coral tree 

coral tree (falcata) 

coral vine 

coralberry 

coreopsis 

cork oak 

corokia 

Costa Rica blue sage 

Costa Rican nightshade 

cotoneaster 

cotoneaster 

cottonless cottonwood 

cotyledon 

Coulter pine 

cowslip 

coyote brush 

coyote mint 

crabapple 

cranesbill 

cranessbill (chrysanthum) 

crape myrtle 

crassula 

creeping baby's breath 

creeping buttercup 

creeping coprosma 

creeping fig 

creeping forget-me-not 

creeping globe daisy 

creeping gloxinia 

creeping mahonia 

creeping red fescue 

creeping snowberry 

creeping wintergreen 

creeping wire vine 

creeping/Sonoma sage 

creosote 

crepe fern 

crinum lily, spider lily 

cross vine 

crown of thorns 

cruel vine 

Cuayamaca cypress 

cup and saucer vine 

cup flower 

cup of gold vine 

cuphea (micropetala) 

cupid's dart 

cushion bush 


Rudbeckia spp. 

Hibiscus mutabilis 

Eucalyptus microtheca 

Castanopsis cuspidata 

Heuchera sanguinea 

Eucalyptus torquata 

Berberidopsis corallina 

Kniphofia triangularis (galpinii) 

Erythryna X bidwillii 

Erythrina falcata 

Antigonon leptopus 

Symphoricarpus orbiculatus 

Coreopsis lanceolata 

Quercus suber 

Corokia X virgata 

Salvia 'Costa Rica Blue' 

Solanum wendlandii 

Cotoneaster spp. (shrubs) 

Cotoneaster spp.(ground covers) 

Populus 'Red Caudina' 

Cotyledon spp. 

Pinus coulteri 

Lachenalia spp. 

Baccharis pilularis consanguinea 

Monardella villosa 

Malus hybrids 

Geranium spp. 

Erodium chrysanthum 

Lagerstroemia indica 

Crassula spp. 

Gypsophila repens 

Ranunculus repens 

Coprosma X kirkii 

Ficus pumila 

Omphalodes verna 

Globularia cordifolia 

Asarina erubescens (Maurandya) 

Mahonia repens 

Festuca rubra 

Symphoricarpus mollis 

Gaultheria procumbens 

Muehlenbeckia axillaris 

Salvia sonomensis 

Larrea tridentata 

Todea barbara 

Crinum spp. 

Bignonia capreolata 

Euphorbia milii 

Araujia sericifera 

Cupressus arizonica ssp. arizonica 

Cobaea scandens 

Nierembergia hippomanica 

Solandra maxima 

Cuphea micropetela 

Catananche caerulea 

Calocephalus brownii 

109


COMMON NAME 

cushion spurge 

cut-leaf banksia 

cut leaf Guinea flower 

cyclamen 

cypress spurge 

daffodil 

dahlia 

daisy tree 

dalea (bicolor) 

dalea (capitata) 

dalea (dorychnioides) 

dalea (lutea) 

dalea (versicolor) 

dampiera 

dampiera 

daphne (caucasia) 

Darcy sage 

date palm 

David viburnum 

dawn redwood 

day lily 

deciduous clematis 

deer fern 

deer grass 

deer weed 

delphinium 

dendriopoterium 

deodar cedar 

desert bird of paradise 

desert broom 

desert bunch grass 

desert cassia 

desert grape 

desert honeysuckle 

desert ironwood 

desert lavender 

desert marigold 

desert olive 

desert spoon 

desert sweet acacia 

desert willow 

desert/globe mallow 

dichondra 

dittany/oregano etc. 

dobo lily 

dombeya 

double mock orange 

doublefile viburnum 

Douglas iris hybrids 

dragon tree 

drooping laurel 

drumsticks 

dudleya, live forever 

dusky coral pea 

dusty miller 

dusty miller (cineraria) 


Euphorbia polychroma (epithymoides) 

Banksia praemorsa 

Hibbertia cuniformis 

Cyclamen hederifolium 

Euphorbia cyparissias 

Narcissus spp. 

Dahlia spp. 

Montanoa grandiflora 

Dalea bicolor 

Dalea capitata 

Dalea dorychnioides 

Dalea lutea 

Dalea versicolor 

Dampiera diversifolia 

Dampiera trigona 

Daphne caucasica 

Salvia darcyi 

Phoenix dactylifera 

Viburnum davidii 

Metasequoia glyptostroboides 

Hemerocallis spp. 

Clematis hybrids and cvs 

Blechnum spicant 

Muhlenbergia rigens 

Lotus scoparius 

Delphinium spp. 

Dendriopoterium menendezii 

Cedrus deodora 

Caesalpinea gilliesii 

Baccharis sarothroides 

Stipa stipa spinosa 

Cassia eremophila (C.nemophila) 

Vitis girdiana 

Anisacanthus spp. 

Olneya tesota 

Hyptis emoryi 

Baileya multiradiata 

Forestiera neomexicana 

Dasylirion spp. 

Acacia smallii 

Chilopsis linearis 

Sphaeralcea spp. 

Dichondra micrantha 

Origanum spp. 

Cyrtanthus brachyscyphus 

Dombeya spp. 

Philadelphus X virginalis 

Viburnum plicatum tomentosum 

Iris spp. 

Dracaena draco 

Leucothoe fontanesiana 

Craspedia globosa 

Dudleya spp. 

Kennedia rubicunda 

Senecio cineraria 

Centaurea cineraria 

110


COMMON NAME 

Dutchman's pipe 

dwarf arrow bamboo 

dwarf bamboo 

dwarf coreopsis 

dwarf coyote brush 

dwarf fothergilla 

dwarf jasmine 

dwarf pittosporum 

dwarf plumbago 

dwarf poinciana 

dwarf pomegranate 

dwarf powderpuff 

dwarf ruellia 

dwarf snapdragon 

dwarf umbrella plant 

dyckia 

dymondia 

Easter egg bush 

Easter lily vine 

eastern black walnut 

eastern dogwood 

eastern redbud 

eastern white pine 

Ebbinge's silverberry 

Eddie's white wonder dogwood 

edible fig 

edible pear 

eidelweiss 

eight-day-healing bush 

eldarica pine 

elderberry 

elephant tree 

elephant's ear 

elephant's food 

empress tree 

emu bush 

English boxwood 

English daisy 

English holly 

English ivy 

English laurel 

English oak 

English walnut 

English yew 

epidendrum 

escallonia 

escarpment live oak 

eucryphia 

eulalia grass 

eumong/shoestring acacia 

euonymus 

euphorbia 

euphorbia 

euphorbia 

euphorbia 

euphorbia (dulsis) 


Aristolochia durior 

Pseudosasa japonica tsutsumiana 

Pleioblastus spp. 

Coreopsis auriculata'Nana' 

Baccharis pilularis cvs. 

Fothergilla gardenii 

Jasminum parkeri 

Pittosporum tobira 'Wheelers Dwarf' 

Ceratostigma plumbaginoides 

Caesalpinea pulcherrima 

Punica granatum 'Nana' 

Calliandra emarginata 

Ruellia X brittoniana 

Chaenorhinium glareosum 

Cyperus albostriatus 

Dyckia spp. 

Dymondia margaretae 

Eremophila racemosa 

Beaumontia grandiflora 

Juglans nigra 

Cornus florida 

Cercis canadensis 

Pinus strobus 

Eleagnus X ebbengei 

Cornus 'Eddie's White Wonder' 

Ficus carica 

Pyrus communis 

Leontopodium alpinium 

Lobostemon fruiticosus 

Pinus brutia ssp. eldarica 

Sambucus spp. 

Pachycormis discolor 

Alocasia spp. 

Portulacaria afra 

Paulownia tomentosa 

Eremophila glabra 

Buxus sempervirens 

Bellis perenis 

Ilex aquifolium 

Hedera helix 

Prunus lauroceracus 

Quercus robur 

Juglans regia 

Taxus baccata 

Epidendrum reed stem hybrids 

Escallonia spp. 

Quercus fusiformis 

Eucryphia x intermedia 

Miscanthus sinensis 

Acacia stenophyla 

Euonymus kiautschovicus 

Euphorbia characias 

Euphorbia myrsinites 

Euphorbia rigida 

Euphorbia segueriana niciciana 

Euphorbia dulsis 

111


COMMON NAME 

European beech 

European chain fern 

European cranberry bush 

European grape 

European hackberry 

European hornbeam 

European larch 

European mountain ash 

European white birch 

euryops/shrub daisy 

evening primrose (pallida) 

evening primrose (rosea) 

evergreen ash 

evergreen candy tuft 

evergreen clematis 

evergreen currant 

evergreen dogwood 

evergreen eulalia 

evergreen euonymus 

evergreen grape 

evergreen huckleberry 

evergreen hydrangea 

evergreen maple (oblongum) 

evergreen maple (paxii) 

evergreen mock orange 

evergreen pear 

evergreen pittosporum 

evergreen sumac 

evergreen sumac 

evergreen wisteria 

evolvulus 

eyelash-leafed sage 

fairy duster 

fairy wand 

false cypress 

false heather 

false indigo 

false indigobush 

false mallow 

false mallow 

false spirea 

fan flower 

farfugium/ligularia 

fascicularia 

feather bush 

feather grass 

feather reed 

feathery cassia/senna 

felt fern 

fern leaf yarrow 

fescue (cinerea) 

fescue (tenuifolia) 

feverfew 

filbert 

fir 

fire lily 


Fagus sylvatica 

Woodwardia radicans 

Viburnum opulus 

Vitis vinifera 

Celtis australis 

Carpinus betulus 'Fastigiata' 

Larix decidua 

Sorbus aucuparia 

Betula pendula 

Euryops pectinatus 

Oenothera pallida 

Oenothera rosea 

Fraxinus uhdei 

Iberis sempervirens 

Clematis armandii 

Ribes viburnifolium 

Cornus capitata 

Miscanthus transmorrisonensis 

Euonymus japonicus 

Rhoicissus capensis 

Vaccinium ovatum 

Dichroa febrifuga 

Acer oblongum 

Acer paxii 

Philadelphus mexicanus 

Pyrus kawakamii 

Pittosporum crassifolium 

Rhus choriophylla 

Rhus virens 

Milletia reticulata 

Evolvulus pilosus (nuttallianus) 

Salvia blepharophylla 

Calliandra eriophylla 

Dierama spp. 

Chamaecyparis spp. 

Cuphea hyssophyla 

Baptista australis 

Amorpha fruiticosa 

Anisodontea scabrosa 

Sidalcea spp. 

Astilbe hybrids 

Scaevola 'Mauve Clusters' 

Farfugium japonicum (Ligularia) 

Fascicularia pitcairnifolia 

Lysiloma microphylla var. thornberi 

Stipa pulchra 

Calamagrostis spp. 

Senna artemesioides (Cassia artemesioides) 

Pyrrosia spp. 

Achillea filipendulina 

Festuca cinerea 

Festuca tenuifolia 

Tanacetum parthenium (Chrysanthemum parthenium) 

Corylus maxima 

Abies spp. 

Cyrtanthus purpureus 

112


COMMON NAME 

Firescape sage 

firespike 

firethorn 

firewheel tree 

fishtail wine palm 

fiveleaf akebia 

flame flower 

flame pea 

flame tree 

flame vine 

flannel bush 

flax 

flax 

flax leaf paper bark 

fleabane 

fleabane 

flooded gum 

flooded/rose gum 

Florida arrowroot 

Florida fig 

florists' cyclamen 

floss silk tree 

flower-of-an-hour 

flowering cherry 

flowering maple 

flowering peach 

flowering plum 

flowering quince 

flowering woodbine 

foothill needlegrass 

foothill stipa 

foothill/Gray pine 

forest bell bush 

forest Boer bloom 

forest lily 

forest oak 

forget-me-not 

Forman's mallee 

forsythia 

forsythia sage 

fortnight lily 

fortnight lily 

fountain butterfly bush 

fountain grass 

four o'clock 

foxberry 

foxglove 

fragrant Himalayan champaca 

fragrant sarcococca 

fragrant sumac 

frangipani 

franklin tree 

Fraser photinia 

Freeman maple 

Fremont silktassel 

Fremont's bush mallow 


Salvia 'Firescape' 

Odontonema strictum 

Pyracantha spp. 

Stenocarpus sinuatus 

Caryota urens 

Akebia quinata 

Talinium calcynium 

Chorizema cordata 

Brachychiton acerifolius 

Pyrostegia venusta 

Fremontodendron spp. 

Phormium hybrids 

Linum spp. 

Melaleuca linariifolia 

Erigeron formosissimus 

Erigeron karvinskianus 

Eucalyptus rudis 

Eucalyptus grandis 

Zamia pumila 

Ficus florida 

Cyclamen persicum hybrids 

Chorisia speciosa 

Hibiscus trionum 

Prunus spp. (ornamental) 

Abutilon X hybridum 

Chaenomeles cvs. 

Lonicera periclymenum 

Nassella lepida 

Stipa lepida 

Pinus sabiniana 

Mackaya bella 

Schotia latifolia 

Velthemia bracteata 

Allocasuarina torulosa 

Myosotis scorpioides 

Eucalyptus formanii 

Forsythia X intermedia 

Salvia madrensis 

Dietes bicolor 

Dietes iridioides 

Buddleja alternifolia 

Pennisetum setaceum 

Mirabilis jalapa 

Vaccinium vitis-idaea 

Digitalis X mertonensis 

Michelia champaca 

Sarcococca ruscifolia 

Rhus aromatica 

Plumeria rubra 

Franklinia alatamaha (Gordonia) 

Photinia X fraseri 

Acer X freemanii 

Garrya fremontii 

Malacothamnus fremontii 

113


COMMON NAME 

fringe cups 

fringe flower 

fuchsia 

fuchsia begonia 

fuchsia flowering gooseberry 

furcraea 

Galpin's leucadendron 

gamolepis 

garden geranium 

garden monkshood 

garden verbena 

garden/kitchen sage 

gardenia 

garland lily 

gaura 

gay feather 

gazania 

gentian 

gentian sage 

Geraldton wax flower 

geranium (sidoides) 

germander 

germander (crispum) 

germander (hyrcanicum) 

giant bird of paradise 

giant Burmese honeysuckle 

giant chain fern 

giant coreopsis 

giant four o'clock 

giant hyssop 

giant lily turf 

giant needle grass 

giant reed 

giant sequoia 

giant thevetia 

Gibraltar candytuft 

gladiolus 

gladiolus 

globe daisy 

globe thistle 

globeflower 

glory bower 

glory bush 

glossy abelia 

glossy privet 

gold coin 

gold coin, Canary Island daisy 

gold flower 

gold medallion tree 

golden-eyed grass 

golden abundance mahonia 

golden chain tree 

golden currant 

golden fleece 

golden foxtail 

golden larch 


Tellima grandiflora 

Loropetalum chinense 

Fuchsia spp. 

Begonia fuchoides rosea 

Ribes speciosum 

Furcraea spp. 

Leucadendron galpinii 

Gamolepis chrysanthemumoides 

Pelargonium X hortorum 

Aconitum napellus 

Verbena hybrids 

Salvia officinalis 

Gardenia spp. 

Calostemma purpureum 

Gaura lindheimeri 

Liatris spicata 

Gazania spp. 

Gentiana scabra procumbens 

Salvia patens 

Chamelaucium uncinatum 

Pelargonium sidoides 

Teucrium chamaedrys 

Teucrium scorodonia 'Crispum' 

Teucrium hyrcanicum 

Strelitzia nicolai 

Lonicera hildebrandiana 

Woodwardia fimbriata 

Coreopsis gigantea 

Mirabilis multiflora 

Agastache aurantica 

Ophiopogon jaburan 

Stipa gigantea 

Arundo donax 

Sequoiadendron giganteum 

Thevetia thevetioides 

Iberis gibraltarica 

Gladiolus spp. 

Gladiolus hybrids & selections 

Globularia X indubia 

Echinops exaltus 

Trollius spp. 

Clerodendrum phillippinum 

Tibuchina heteromalla 

Abelia X grandiflora 

Ligustrum lucidum 

Odontospermum hybrida 

Asteriscus maritimus 

Hypericum X moseranum 

Cassia leptophylla 

Sisyrinchium californicum 

Mahonia 'Golden Abundance' 

Laburnum X watereri 

Ribes aureum 

Dyssodia pentachaeta 

Alopecurus pratensis 'Aureus' 

Pseudolarix kaempheri 

114


COMMON NAME 

golden privet 

golden rain tree 

golden scabweed 

golden sundrops 

golden sunflower 

golden trumpet tree 

golden trumpet vine 

golden wonder 

golden wood millet 

golden yarrow 

goldenbush 

goldeneye 

Goldman's senna/cassia 

Goodding verbena 

gordonia 

Gowen cypress 

granite honey-myrtle 

grape hyacinth 

grape ivy 

grape soda lupine 

grapefruit-scented sage 

graptopetalum 

grass tree 

grassy bells 

graythorn 

great blue lobelia 

greater masterwort 

greater woodrush 

Grecian horehound 

Greek yarrow 

green ash 

green carpet 

green euryops 

green gem ficus 

green kangaroo paw 

green wattle 

grevillea 

grey honey-myrtle 

Griffith ash 

ground ivy 

ground morning glory 

groundsel 

Guadalupe island rock daisy 

Guadalupe palm 

guajillo 

Guatemalan blue sage 

Guatemalan holly 

Guinea gold vine 

gum myrtle 

gum plant 

gunnera 

habranthus 

hairy awn muhly 

hairy canary clover 

hairy golden aster 

hairy lip fern 


Ligustrum X vicaryi 

Koelreuteria paniculata 

Raoulia australis 

Oenothera fruiticosa 

Heliopsis helianthoides scabra 

Tabebuia chrysotricha 

Allamanda cathartica 

Senna splendida (Cassia splendida) 

Milium effusum 

Eriophyllum confertiflorum 

Isocoma spp. (Haplopappus) 

Viguiera deltoidea 

Senna polyantha (Cassia goldmanii) 

Verbena gooddingii 

Gordonia axillaris 

Cupressus goveniana 

Melaleuca elliptica 

Muscari macrocarpum 

Cissus rhombifolia 

Lupinus excubitus 

Salvia dorisiana 

Graptopetalum spp. 

Xanthorrhoea spp. 

Edraianthus graminifolius 

Ziziphus obtusifolia 

Lobelia siphilitica 

Astrantia major rosea 

Luzula sylvatica 

Ballota pseudodictamnus 

Achillea ageratifolia 

Fraxinus pennsylvanica'Marshal' 

Herniaria glabra 

Euryops pectinatus viridis 

Ficus microcarpa 'Green Gem' 

Anigozanthos viridis 

Acacia decurrens 

Grevillea spp. 

Melaleuca incana 

Fraxinus griffithi 

Glechoma hederaceae 

Convolvulus sabatius 

Brachyglottis greyi (Senecio greyi) 

Perityle incana 

Brahea edulis 

Acacia berlandieri 

Salvia cacaliaefolia 

Olmediella betschleriana 

Hibbertia scandens 

Angophora cordifolia (Angophora costata) 

Grindelia camporum 

Gunnera magellanica 

Habranthus tubispathus 

Muhlenbergia capillaris 

Dorycnium hirsutum 

Heterotheca villosa (chrysopsis villosa) 

Cheilanthes lanosa 

115


COMMON NAME 

hairy wattle 

hakone grass 

Hall's honeysuckle 

halmiocistus 

halmiocistus 

hammock fern 

Hardijizer's beauty 

hardy alyssum/basket of gold 

hardy begonia 

hardy eucryphia 

hardy/straw foxglove 

harlequin glory bower 

Harry Lauder's walking stick 

Hart's tongue fern 

Hawaiian elf schefflera 

Hawaiian snow bush 

Hawaiian tree fern 

haworthia 

hawthorn 

heart-leaved penstemmon 

heartleaf bergenia 

heartleaf geranium 

heath 

heath-leafed banksia 

heath melaleuca 

heavenly bamboo 

heavenly bamboo (Nana) 

heavenly blue 

hebe 

hedge maple 

helianthemum 

Henry St. John's wort 

hens and chickens 

heron's-bill 

hesperantha 

hibbertia (aspera) 

hibbertia (pedunculata) 

hibbertia (vestita) 

Himalayan blueberry 

Himalayan ivy 

hippolytia 

hoary pea 

hoary vervian 

holly fern 

holly leaf cherry 

holly oak 

holly sweetspire 

hollyleaf redberry 

honey bush 

honey locust 

Honey mesquite 

honeysuckle (confusa) 

honeysuckle (hispidula) 

Hong Kong orchid tree 

hopseed bush 

hopseed bush (procumbens) 


Acacia vestita 

Hakonechloa macra 

Lonicera japonica 'Halliana' 

X Halimiocistus sahucci 

X Halmiocistus wintonensis 

Blechnum occidentale 

Azaliadendron 'Hardjizer's Beauty' 

Aurinia saxatilis 

Begonia grandis 

Eucryphia glutinosa 

Digitalis lutea 

Clerodendrum trichotomun 

Corylus avelleana contorta 

Asplenium scolopendrium (Phyllitis) 

Schefflera arboricola 

Breynia nivosa (distacha) 

Cibotium glaucum 

Haworthia spp. 

Crataegus spp. 

Keckiella cordifolia 

Bergenia cordifolia 

Pelargonium cordifolium 

Erica spp. 

Banksia ericifolia 

Melaleuca ericifolia 

Nandina domestica 

Nandina domestica 'Purpurea' 

Lithodora diffusa 

Hebe spp. 

Acer campestre 

Helianthemum nummularium 

Hypericum beanii 

Echeveria spp. 

Erodium corsicum 

Hesperantha spp. 

Hibbertia aspera 

Hibbertia pedunculata 

Hibbertia vestita 

Vaccinium moupinense 

Hedera nepalensis 

Hippolytia herderi (Tanacetum herderi) 

Tephrosia grandiflora 

Verbena stricta 

Cyrtomium falcatum 

Prunus ilicifolia 

Quercus ilex 

Itea ilicifolia 

Rhamnus croceus ilicifolia 

Melianthus major 

Gleditsia triacanthos 

Prosopis glandulosa glandulosa 

Lonicera confusa 

Lonicera hispidula 

Bauhinia X blakeana 

Dodonaea viscosa 

Dodonaea procumbens 

116


COMMON NAME 

horned violet 

horsetail 

houpara 

house leek 

hummingbird/pitcher sage 

hyacinth bean 

hyacinth orchid 

hybrid brachychiton 

hybrid leucadendron 

hybrid magnolias 

hydrangea 

hypericum ( e. nanum) 

hypericum ( frondosum) 

ice plant (Aptenia) 

ice plant (Carpobrotus) 

ice plant (Cephalophyllum) 

ice plant (Delosperma) 

ice plant (Drosanthemum) 

ice plant (Lampranthus) 

ice plant (Maleophora) 

ice plant (Red Apple) 

Idaho fescue 

impatiens (uguensis) 

incense cedar 

Indian hawthorne 

Indian laurel fig/ laurel fig 

indian mallow 

Indian mock strawberry 

indigo/pea bush 

inside-out flower 

interior live oak 

inula 

inyouchikuzoku 

Irish heath 

Irish moss 

Irish yew 

Irish, Scotch moss 

island alum root 

island bush snapdragon 

island oak 

isoplexis 

Italian alder 

Italian Arum 

Italian buckthorn 

Italian cypress 

Italian jasmine 

Italian stone pine 

Ithuriel's spear 

ivy geranium 

jacaranda 

Jack Fogg michelia 

Jacob's ladder 

Jacob's rod/kings spear 

Japanese anemone 

Japanese aralia 

Japanese ardesia, marlberry 


Viola cornuta 

Equisetum spp. 

Pseudopanax lessonii 

Sempervivum spp. 

Salvia spathacea 

Labab purpureus (Dolichos labab) 

Bletilla striata 

Brachychiton X hybridus 

Leucadendron hybrids 

Magnolia hybrids 

Hydrangea macrophylla 

Hypericum empetrifolium nanum 

Hypericum frondosum 

Aptenia cordifolia 

Carpobrotus spp. 

Cephalophyllum spp. 

Delosperma spp. 

Drosanthemum spp. 

Lampranthus spp. 

Maleophora spp. 

Aptenia 'Red Apple' 

Festuca idahoensis 

Impatiens uguensis 

Calocedrus decurrens 

Rhaphiolepis indica 

Ficus microcarpa 

Abutilon palmeri 

Duchesnea indica 

Dalea pulchra 

Vancouveria spp. 

Quercus wislizeni 

Inula ensifolia 

Hibanobambusa tranquillans 

Daboecia cantabrica 

Sagina subulata 

Taxus baccata 'Fastigiata' 

Arenaria spp. (See Sagina) 

Heuchera maxima 

Galvesia speciosa 

Quercus tomentella 

Isoplexis chalcantha 

Alnus cordata 

Arum italicum 

Rhamnus alaternus 

Cupressus sempervirens 

Jasminum humile 

Pinus pinea 

Tritelia laxa 

Pelargonium peltatum 

Jacaranda mimosifolia 

Michelia X foggi 'Jack Fogg' 

Polemonium spp. 

Asphodeline lutea 

Anemone X hybrida 

Fatsia japonica 

Ardisia japonica 

117


COMMON NAME 

Japanese aucuba 

Japanese black pine 

Japanese blood grass 

Japanese blueberry tree 

Japanese boxwood 

Japanese cryptomeria 

Japanese dogwood 

Japanese false oak 

Japanese honeysuckle 

Japanese iris 

Japanese knotweed 

Japanese lace fern 

Japanese maple 

Japanese mountain birch 

Japanese pagoda tree 

Japanese persimmon 

Japanese privet 

Japanese red pine 

Japanese rose 

Japanese rose 

Japanese skimmia 

Japanese snowbell 

Japanese spurge 

Japanese stewartia 

Japanese ternstroemia 

Japanese umbrella pine 

Japanese viburnum 

Japanese white pine 

Japanese yew 

jasmine (beesianum) 

jasmine (leratii) 

jasmine (tortulosum 

Javan grape 

Jeffrey pine 

Jelecote pine 

Jerusalem sage 

jojoba 

jubilee wallflower 

Judas tree 

jungle geranium 

juniper 

justicia (leonardii) 

Kaffir bloom coral tree 

Kaffir lily 

Kaffir lily 

Kaffir plum 

Kahili ginger 

kalanchoe 

kangaroo apple 

kangaroo paw 

kangaroo treebine 

kapuka 

Karwinski's sage 

Katsura tree 

Keller hypericum 

kellerii achillea 


Aucuba japonica 

Pinus thumbergii 

Imperata cylindrica 'Rubra' 

Elaeocarpus decipiens 

Buxus microphylla japonica 

Cryptomeria japonica 

Cornus kousa 

Lithocarpus edulis (Pasania edulis) 

Lonicera japonica 

Iris spp. 

Fallopia japonica 

Polystichum polyblepharum 

Acer palmatum 

Betula platyphyla japonica 

Sophora japonica 

Diospyros kaki 

Ligustrum japonicum 

Pinus densiflora 

Kerria japonica 

Rosa rugosa 

Skimmia japonica 

Styrax japonicum 

Pachysandra terminalis 

Stewartia pseudocamellia 

Ternstroemia gymnanthera 

Sciadopitys verticillata 

Viburnum japonicum 

Pinus parviflora 

Taxus cuspidata 

Jasminum beesianum 

Jasminum leratii 

Jasminum tortuosum 

Tetrastigma voinieranum 

Pinus jeffreyi 

Pinus patula 

Phlomis fruticosa 

Simmondsia chinensis 

Erysimum 'Jubilee' 

Cercis siliquastrum 

Ixora coccinia 

Juniperus spp. 

Justicia leonardii 

Erythrina caffra 

Clivia miniata 

Schizostylis coccinia 

Harpephyllum caffrum 

Hedychium garnerianum 

Kalanchoe spp. 

Solanum aviculaare 

Anigozanthos flavidus 

Cissus antarctica 

Griselinia littoralis 

Salvia karwinskii 

Cercidiphyllum japonicum 

Hypericum kelleri 

Achillea X kellerii 

118


COMMON NAME 

Kenilworth ivy 

Kentia palm 

Kew broom 

king palm 

kiwi 

kiwi/Tara 

kleinia 

knife acacia 

knobcone-Monterey pine 

knobcone pine 

Korean lilac 

Korean spice viburnum 

kunzea 

Labrador violet 

lace fern 

lacecap hydrangea 

Lady Banks rose 

lady fern 

lady palm 

ladybells 

lambertia 

lamb's ears 

lantana 

lantern tree 

laurel leaf cocculus 

laurel sumac 

laurustinus 

lavatera 

lavender 

lavender beautyberry 

lavender cotton 

lavender mist 

lavender shower 

lavender star flower 

leather leaf fern 

leatherleaf acacia 

leatherleaf mahonia 

leatherleaf viburnum 

leatherwood 

Lehua of Hawaii 

lemon balm 

lemon flowered gum 

lemon scented gum 

lemon scented jasmine 

lemon scented tea tree 

lemon verbena 

lemonade berry 

leopard's bane 

lewisia 

Leyland cypress 

libertia 

licorice plant 

lilac 

lilac verbena 

lilac vine 

lily 


Cymbalaria muralis 

Howea forsterana 

Cytisus X kewensis 

Archontophoenix cunninghamiana 

Actinidia deliciosa 

Actinidia arguta 

Senecio mandraliscae 

Acacia cultriformis 

Pinus X attenuradiata 

Pinus attenuata 

Syringa patula 

Viburnum carlesii 

Kunzea spp. 

Viola labradorica 

Microlepia strigosa 

Hydrangea aspera villosa 

Rosa banksiae 

Athyrium filix-femina 

Rhapis excelsa 

Adenophora bulleyana 

Lambertia intermis 

Stachys byzantina 

Lantana camara 

Crinodendron hookerianum 

Cocculus laurifolius 

Malosma laurina (Rhus laurina) 

Viburnum tinus 

Lavatera hybrids 

Lavandula spp. 

Callicarpa dichotoma 

Santolina spp. 

Thalictrum rochenbrunianum 

Thalictrum delavayi 

Grewia occidentalis 

Rumohra adiantiformis 

Acacia craspedocarpa 

Mahonia bealei 

Viburnum rhytidophyllum 

Eucryphia lucida (billardieri) 

Metrosideros collinia 

Melissa officinalis 

Eucalyptus woodwardii 

Eucalyptus citriodora 

Jasminum azoricum 

Leptospermum petersonii 

Aloysia triphylla 

Rhus integrifolia 

Doronicum orientale (D. caucasium) 

Lewisia hybrids 

X Cupressocyparis leylandii 

Libertia spp. 

Helichrysum petiolare 

Syringa vulgaris 

Verbena lilacina 

Hardenbergia violacea 

Lilium (garden hybrids) 

119


COMMON NAME 

lily-of-the-Nile 

lily-of-the-valley shrub 

lily-of-the-valley tree 

lilyleaf ladybells 

lilyturf 

limber pine 

Lindheimer muhly 

Lindheim's senna/cassia 

lion's tail 

little cabbage tree 

little leaf cordia 

little leaf linden 

little leaf myrtle 

little leaf palo verde 

little Tyler/blue stars 

littleaf sumac 

livistona (rigida) 

lob lolly bay 

lobelia (chinensis) 

lobelia (ricardii) 

locust 

loebner magnolia 

Lombardy poplar 

London plane 

long flowered marlock 

long leaf yellow wood 

longleaf mahonia 

loosestrife/moneywort 

loquat 

low bull rush 

luculia 

Ludgvan cross agapetes 

lungwort 

Lydia woadwaxen 

macadamia nut 

Madagascar jasmine 

Madagascar palm 

Madagascar periwinkle 

madrone 

magic flower 

maiden hair tree 

maidenhair fern 

majestic beauty 

Majorcan germander 

male fern 

mallow rose 

Maltese cross 

mandevilla 

manfreda 

mangle dulce 

maniko 

manna gum 

manzanita 

manzanita cultivars 

maraschino sage 

marbled bamboo 


Agapanthus africanus 

Pieris japonica (taiwanensis) 

Crinodendron patagua 

Adenophora liliifolia 

Liriope spp. 

Pinus flexilis 

Muhlenbergia lindheimeri 

Senna lindheimeriana (Cassia lindheimeriana) 

Leonotis leonurus 

Cussonia paniculata 

Cordia parvifolia 

Tilia cordata 

Tristaniopsis laurina 

Cercidium microphyllum 

Aristea ecklonii 

Rhus microphylla 

Livistona rigida 

Gordonia lasianthus 

Lobelia chinensis 

Lobelia ricardii 

Robinia X ambigua 

Magnolia X loebneri 

Populus nigra 'Italica' 

Platanus X acerifolia and cvs. 

Eucalyptus macranda 

Podocarpus henkelii 

Mahonia nervosa 

Lysimachia spp. 

Eryobotrya japonica 

Isolepis cernua (Scirpus cernuus) 

Luculia pinceana 

Agapetes 'Ludgvan Cross' 

Pulmonaria spp. 

Genista lydia 

Macadamia spp. 

Stephanotis floribunda 

Pachypodium lamerei 

Catharanthus roseus 

Arbutus menziesii 

Cantua buxifolia 

Ginkgo biloba 

Adiantum spp. 

Rhaphiolepis 'Majestic Beauty' 

Teucrium cossonii 

Dryopteris felix-mas 

Hibiscus moscheutos 

Lychnis chalcedonica 

Mandevilla splendens 

Manfreda spp. 

Maytenus phyllanthoides 

Salvia koyamae 

Eucalyptus viminalis 

Arctostaphylos spp. 

Arctostaphylos cultivars 

Salvia 'Maraschino' 

Chimonobambusa marmorea (Arundinarea) 

120


COMMON NAME 

Marguerite daisy 

Marina arbutus 

markhamia 

marmalade bush 

Martha Washington pelargonium 

Mascarene grass 

mastic tree 

Matilija poppy 

mattress vine 

Maximilian sunflower 

May lily 

mayten tree 

mazus 

meadow rue 

meadow rue (coreanum) 

meadow rue (flavum) 

Meadowsweet 

Mediterranean fan palm 

medow rue 

medow sage 

melaleuca (fulgens) 

merremia (aurea) 

merremia (quinquefolia) 

mesa oak 

Mexican abelia 

Mexican bird of paradise 

Mexican buckeye 

Mexican bush lobelia 

Mexican bush sage 

Mexican cardinal flower 

Mexican cardinal sage 

Mexican cycad 

Mexican fan palm 

Mexican feather grass 

Mexican flame vine 

Mexican hat 

Mexican honeysuckle 

Mexican lily 

Mexican orange 

Mexican oregano 

Mexican palo verde/ Jerusalem thorn 

Mexican pitcher sage 

Mexican redbud 

Mexican sage 

Mexican tarragon 

Mexican tulip poppy 

Mexican weeping bamboo 

Mexican/white evening primrose 

Meyer's Yew 

milk bush 

milk/silk weed 

mindinao gum 

mint 

mint bush 

mirror plant 

mission manzanita 


Argyranthemum frutescens 

Arbutus 'Marina' 

Markhamia lutea (hildebrandtii) 

Streptosolen jamesonii 

Pelargonium domesticum 

Zoyzia tenuifolia 

Pistacia lentiscus 

Romneya coulteri 

Muehlenbeckia complexa 

Helianthus maximiliani 

Maianthemum dilatatum 

Maytenus boaria 

Mazus reptans 

Thalictrum fendleri var. polycarpum 

Thalictrum coreanum 

Thalictrum flavum spp glaucum 

Filipendula vulgaris 

Chamaerops humilis 

Thalictrum polycarpum 

Salvia pratensis haematodes 

Melaleuca fulgens 

Merremia aurea 

Merremia quinquefolia 

Quercus engelmannii 

Abelia floribunda 

Caesalpinea mexicana 

Ungnadia speciosa 

Lobelia laxiflora 

Salvia leucantha 

Lobelia fulgens 

Salvia fulgens 

Dioon spp. 

Washingtonia robusta 

Stipa tenuissima 

Pseudogynoxys chenopodiodes (Senecio) 

Ratibida columnifera 

Justicia spicigera 

Beschorneria yuccoides 

Choisya ternata 

Poliomintha longiflora 

Parkinsonia aculeata 

Lepechinia hastata 

Cercis mexicana 

Salvia mexicana 

Tagetes lucida 

Hunnemannia fumarifolia 

Otatea acuminata (aztecorum) 

Oenothera speciosa 

Taxus 'Meyeri' 

Euphorbia tirucalli 

Asclepias (wild species) 

Eucalyptus deglupta 

Mentha spp. 

Prostanthera denticulata 

Coprosma repens 

Xylococcus bicolor 

121


COMMON NAME 

mistflower 

mock orange 

Modesto ash 

Mohave poplar 

Mohawk viburnum 

mondo grass 

monkey flower 

monkey flower 

monkey puzzle tree 

monochaetum 

montbrieta 

Monterey cypress 

Monterey pine 

Montezuma cypress 

Montezuma pine 

Moor grass 

Moor grass 

moraea 

moraine ash 

morea 

Moreton Bay chestnut 

Moreton Bay fig 

Moroccan daisy 

mosquito plant 

moss pink 

moss pink/campion 

moss verbena 

mother-in-law's tongue etc. 

mother fern 

Mount Atlas daisy 

mountain alyssum 

mountain ash 

mountain ironwood 

mountain marigold 

mountain pennyroyal 

mountain sage 

mountain wood rose 

Mrs. Beard sage 

Mueller's fescue 

mugo pine 

mulga 

mullein 

myoporum 

myoporum 

Nageia 

naked coral tree 

naked lady 

Narihira bamboo 

narrow leaf rosewood 

nasturtium 

Natal coral tree 

Natal plum 

Natal plum 

native fleabane 

navelwort 

nealy cup sage 


Eupatorium spp. 

Pittosporum tobira 

Fraxinus velutina 'Modesto' 

Populus 'Mohavensis' 

Viburnum 'Mohawk' 

Ophiopogon japonicus 

Mimulus spp. (shrubby) 

Mimulus spp. (herbaceous) 

Araucaria araucana 

Monochaetum volcanicum 

Crocrosmia hybrids (Tritonia) 

Cupressus macrocarpa 

Pinus radiata 

Taxodium mucronatum 

Pinus montezumae 

Molinia caerulea 

Sesleria spp. 

Moraea spp. (summer growing) 

Fraxinus 'Moraine' 

Moraea spp.(winter growing) 

Castanospermum australe 

Ficus macrophylla 

Pyrethropsis hosmariense 

Agastache cana 

Phlox subulata 

Silene spp. 

Verbena tenuisecta 

Gasteria spp. 

Asplenium bulbiferum 

Anaclycus pyrethrum var depressus 

Alyssum montanum 

Sorbus hupehensis 

Cercocarpus betuloides 

Tagetes lemmoni 

Monardella odoratissima 

Salvia regla 

Rosa woodsii var. ultramontana 

Salvia 'Mrs. Beard' 

Festuca muelleri 

Pinus mugo 

Acacia aneura 

Verbascum bombiciferum 

Myoporum laetum 

Myoporum parvifolium & cvs. 

Nageia nagi (Podocarpus nagi) 

Erythrina americana(E.coralloides) 

Amaryllis belladona 

Semiarundinaria fastuosa 

Vauquelinia corymbosa var. heterodon 

Tropaeolum majus 

Erythrina humeana 

Carissa macrocarpa (prost.cvs.) 

Carissa spp. 

Erigeron divergens 

Omphalodes cappadocica 

Salvia farinacea 

122


COMMON NAME 

nectarine 

needleleaf acacia 

neem 

Nepal holly 

nerine 

net bush 

Nevin mahonia 

New Zealand cabbage tree 

New Zealand cassia/senna 

New Zealand Christmas tree 

New Zealand flax 

New Zealand laurel 

New Zealand tea tree 

Newell cestrum 

Nichol's willow leaf peppermint 

night jessamine 

Nikau palm 

nodding feather grass 

nodding needlegrass 

nodding pincushion 

Norfolk Island pine 

Norfolk palm 

Norway maple 

Norway spruce 

Nutall's scrub oak 

oakleaf hydrangea 

obedient plant 

O'Conners legume(revegetation use) 

O'Connors legume(landscape use) 

ocotillo 

Okame-Zaza bamboo 

Okinawan holly 

old man cactus 

oleander 

olive 

olympic hypericum 

orange cestrum 

orange clock vine 

orange jessamine 

orange jubilee tecoma 

orange sneezeweed 

orange, lemon etc. 

Oregon alder 

Oregon ash 

Oregon fleabane 

Oregon grape 

organ pipe cactus 

oriental arborvitae 

oriental poppy 

oriental spruce 

ornamental asparagus 

orono 

orthrosantus 

orthrosantus 

ostrich fern 

oyama magnolia 


Acacia rigens 

Azadirachta indica 

Ilex integra 

Nerine spp. 

Calothamnus quadrifidus 

Mahonia nevinii 

Cordyline australis 

Senna bicapsularis (Cassia candolleana) 

Metrosideros excelsa 

Phormium tenax 

Corynocarpus laevigata 

Leptospermum scoparium 

Cestrum fasciculatum var. 'Newellii 

Eucalyptus nicholii 

Cestrum nocturnum 

Rhopalostylis sapida 

Stipa cernua 

Nassella cernua 

Leucospermum cordifolium 

Araucaria heterophyla 

Rhopalostylis baueri 

Acer platanoides 

Picea abies 

Quercus dumosa 

Hydrangea quercifolia 

Physostegia virginiana 

Trifolium fragiferum O'Connor 

Trifolium fragiferum O'Connor 

Fouquieria splendens 

Shibatea kumasasa 

Ilex dimorphophilla 

Cephalocereus spp. 

Nerium oleander 

Olea europaea 

Hypericum olympicum 

Cestrum auranticum 

Thunbergia gregorii 

Murraya paniculata 

Tecoma 'Orange Jubilee' 

Helenium hoopesii 

Citrus spp. 

Alnus oregona 

Fraxinus latifolia 

Erigeron speciosus 

Mahonia aquifolium 

Stenocereus thurberi (Lemaireocereus) 

Platycladus orientalis 

Papaver orientale 

Picea orientalis 

Asparagus spp. 

Azara dentata 

Orthrosanthus chimboracensis centroamericanus 

Orthrosanthus multiflorus 

Matteuccia struthiopteris 

Magnolia sieboldii 

123


COMMON NAME 

Ozark sundrops 

ozothamnus 

Pacific wax myrtle 

pacifica saltbush 

painted daisy 

painted lady fern 

palm grass 

palm lily 

palmetto 

palo blanca 

palo blanco 

palo Colorado 

pampas grass 

pampas lily 

paper flower 

paper flower 

paperbark maple 

Paraguay nightshade/blue potato bush M 

parrot's beak 

Pasque flower 

passion vine 

pattersonia 

peach 

peach (low chill only) 

pearl acacia 

pearl bluebush 

pecan 

peegee hydrangea 

pennatula acacia 

penstemon (hybrids) 

penstemon (wild) 

peony 

pepper tree 

peppermint-scented geranium 

peppermint tree 

perennial cornflower 

perennial lobelia 

periwinkle 

periwinkle 

Persian knapweed 

Persian lilac 

Persian witch hazel 

Peruvian apple cactus 

Peruvian lily 

Peruvian lily 

Peruvian old man cactus 

Peruvian pepper 

Peruvian verbena 

phanera 

phlomis (caballeroi) 

phlomis (cashmeriana) 

phlomis (cretica) 

phlomis (italica) 

phlomis (lanata) 

phlomis (purpurea) 

phlomis (russeliana) 


Oenothera macrocarpa 

Ozothamnus rosemarinifolius(Helichrysum) 

Myrica californica 

Myoporum X 'Pacificum' 

Tanacetum coccinium (Pyrethrum roseum) 

Athyrium nipponicum 'Pictum' 

Setaria palmifolia 

Cordyline stricta 

Sabal spp. 

Lysiloma candida 

Acacia willardiana 

Luma apiculata 

Cortaderia sellowana cvs. 

Habranthus robustus (Zephranthes) 

Psilostrophe cooperi 

Psilostrophe tagetina 

Acer griseum 

Lycianthus rantonnetii 

Clianthus puniceus 

Pulsatilla vulgaris (Anemone pulsatilla) 

Passiflora spp. 

Pattersonia drummondii 

Acacia podalyriifolia 

Maireana sedifolia 

Carya illinoensis 

Hydrangea paniculata 'Grandiflora' 

Acacia pennatula 

Penstemon hybrids 

Penstemon wild spp. 

Paeonia spp. 

Drimys lanceolata 

Pelargonium tomentosum 

Agonis flexuosa 

Centaurea montana 

Lobelia richmondensis 

Vinca major 

Vinca minor 

Centaurea dealbata 

Syringa X persica 

Parrotia persica 

Cereus peruvianus 

Alstroemeria spp. 

Scilla peruviana 

Espostoa lantana 

Schinus polygamous 

Verbena peruviana 

Bauhinia corymbosa 

Phlomis caballeroi 

Phlomis cashmeriana 

Phlomis cretica 

Phlomis italica 

Phlomis lanata 

Phlomis purpurea 

Phlomis russeliana 

124


COMMON NAME 

phlomis (tuberosa) 

phlox 

pichi 

pigmy date palm 

pimpernel 

pin oak 

pincushion flower 

pindo palm 

pine-leafed bottlebrush 

pineapple guava 

pineapple lily 

pineapple sage 

pinellia 

pink jasmine 

pink powder puff 

pink tips/white bottlebrush 

pink/carnation 

pink/lavender trumpet tree 

pink/yellow calla lily 

pink-flowering sumac 

pink evening primrose 

pink melaleuca 

pink trumpet vine 

pinyon pine 

pipestem clematis 

pistachio 

pithecoctenium 

plantain lily 

plum 

plum (low chill only) 

plume albizia 

plume grass 

plume poppy 

plypody 

poinsettia 

polypody 

pomegranate 

ponderosa pine 

poor knight's lily 

poor man's orchid 

poor man's rhododendron 

poppy 

porcupine flower 

Portugal laurel 

potato vine 

poverty weed 

Prague viburnum 

prairie flameleaf sumac 

prairie sage 

prairie zinnia 

pratia 

prickly-leaved paperback 

prickly heath 

prickly pear/cholla 

pride of Madeira 

pride of Teneriffe 


Phlomis tuberosa 

Phlox (shrubby cvs.) 

Fabiana imbricana 

Phoenix roebelenii 

Anagallis monellii 

Quercus palustris 

Scabiosa spp. 

Butia capitata 

Callistemon pinifolius 

Acca sellowiana (Feijoa sellowiana) 

Eucomis bicolor hybrids 

Salvia elegans 

Pinellia ternata 

Jasminum polyanthum 

Calliandra haematocephala 

Callistemon salignus 

Dianthus spp. 

Tabebuia impetiginosa (ipe) 

Zantedeschia spp. & hybrids 

Rhus lentii 

Oenothera speciosa 'Rosea' 

Melaleuca nesophila 

Podranea ricasoliana 

Pinus edulis 

Clematis lasiantha 

Pistacia vera 

Pithecoctenium crucigerum 

Hosta spp. 

Albizia distachya 

Erianthus ravennae 

Macleaya spp. 

Polypodium (native spp.) 

Euphorbia pulcherrima 

Polypodium (subtropical spp.) 

Punica granatum 

Pinus ponderosa 

Xeronema calistemon 

Neomarica caerulea 

Impatiens sodeni (oliveri) 

Papaver pilosum 

Centratherum punctatum 

Prunus lusitanica 

Solanum jasminoides 

Iva hayesiana 

Viburnum X pragense 

Rhus lanceolata 

Salvia azurea grandiflora 

Zinnia grandiflora 

Pratia angulata 

Melaleuca styphelioides 

Gaultheria mucronata (Pernettya mucronata) 

Opuntia spp. 

Echium candicans (fastuosum) 

Echium pininana 

125


COMMON NAME 

primrose jasmine 

primrose tree 

princess flower 

prostrate acacia 

protea 

prune 

Pt. Reyes wallflower 

puka 

puka 

purple heart setcreasea 

purple hopseed bush 

purple magesty sage 

purple meadow rue 

purple mullein 

purple needlegrass 

purple nightshade 

purple orchid tree 

purple orchid vine 

purple prairie clover 

purple rain sage 

purple sage 

purple sage 

purple sage, Texas ranger etc. 

purple tower echium 

purple wings 

purple winter creeper 

purple woodrush 

purple/burgundy fountain grass 

pussy toes 

puya 

quaking grass 

queen palm 

queen's tears etc. 

queens wreath 

Queensland bottle tree 

Queensland kauri 

Queensland lace bark 

Queensland pittosporum 

Queensland umbrella tree 

rabbit brush 

rabbit's foot fern 

Raleigh westringia 

rama parda 

ravanea 

raywood ash 

red-barked dogwood 

red-veined enkianthus 

red buckeye 

red cap gum 

red centered hibiscus 

red cestrum 

red flowering currant 

red flowering gum 

red ginger 

red ginger lily 

red gum 


Jasminum mesnyi 

Lagunaria patersonii 

Tibuchina urvilleana (semidecandra) 

Acacia redolens 

Protea spp. 

Erysimum suffrutescens (concinnum) 

Griselinia lucida 

Meryta sinclairii 

Setcreasea pallida 'Purple Heart' 

Dodonaea viscosa 'Purpurea' 

Salvia 'Purple Majesty' 

Thalictrum aquilegifolium 

Verbascum phoeniceum 

Nassella pulchra 

Solanum xantii 

Bauhinia variegata (purpurea) 

Mascagnia lilacina 

Dalea gattingeri (Petalostemum purpureum) 

Salvia verticillata 'Purple Rain' 

Salvia dorrii 

Salvia leucophylla 

Leucophyllum spp. 

Echium 'Purple Tower' 

Dalechampia dioscorifolia 

Euonymus fortunei 

Luzula purpurea 

Pennisetum setaceum cvs, 

Antennaria rosea 

Puya spp. 

Briza media 

Syagrus romanzoffiana 

Billbergia spp. 

Petrea volubilis 

Brachychiton rupestris 

Agathis robusta 

Brachychiton discolor 

Pittosporum rhombifolium 

Schlefflera actinophylla (Brassaia) 

Chrysothamnus nauseosus albicaulis 

Phlebodium aureum (Polypodium aureum) 

Westringia raleighi 

Ruellia californica 

Ravanea rivularis 

Fraxinus oxycarpa 'Raywood' 

Cornus alba 

Enkianthus campanulatus 

Aesculus pavia 

Eucalyptus erythrocorys 

Alyogyne hakeifolia 

Cestrum elegans 

Ribes sanguineum 

Eucalyptus ficifolia 

Hedychium greenei 

Hedychium coccinium 

Eucalyptus camaldulensis 

126


COMMON NAME 

red horsechestnut 

red hot poker 

red huckleberry 

red iron bark 

red justicia 

red oak 

red orchid bush 

red osier dogwood 

red root 

red shanks/ribbonwood 

red tubeflower 

red valerian 

red/ yellow yucca 

redberry 

redwood violet 

Reeves skimmia 

reineckia 

rhagodia 

rhododendron 

rhodophiala 

ribbon bush 

ribbon grass 

rice flower 

rice flower 

rice paper plant 

Richmond begonia 

rigidula acacia 

ring bellflower 

river she-oak 

river/red birch 

rock cress 

rock jasmine 

rock soapwort 

rock verbena 

rockcress 

rockrose 

rogersia (aesculifolia) 

rogersia (pinnata) 

rohdea 

roscoea 

rose 

rose campion/crown pink 

rose cone flower/drumsticks 

rose grass 

rose of Sharon 

roseleaf sage 

rosemary 

round leaf mint bush 

Rowall hypericum 

Roxburgh fig 

royal bluebell 

royal climber 

royal purple autumn sage 

royal trumpet vine 

royal/flowering fern 

rubber plant 


Aesculus X carnea 

Kniphofia uvaria 

Vaccinium parvifolium 

Eucalyptus sideroxylon 

Justicia candicans 

Quercus rubra 

Bauhinia galpinii 

Cornus stolonifera 

Wachendorfia thrysiflora 

Adenostoma sparsifolium 

Iochroma fuchsioides 

Centranthus ruber 

Hesperaloe parviflora 

Rhamnus croceus 

Viola sempervirens 

Skimmia reevesiana 

Reineckia carnea 

Rhagodia deltophylla 

Rhododendron spp. 

Rhodophiala bifida 

Hypoestes aristata 

Phalaris spp. (ornamental) 

Pimelea ferruginia 

Pimelea prostrata 

Tetrapanax papyrifer 

Begonia 'Richmondensis' 

Acacia rigidula 

Symphyandra spp. 

Casuarina cunninghamiana 

Betula nigra 

Aubrieta deltoidea 

Androsace lanuginosa 

Saponaria ocymoides 

Verbena tenera (pulchella) 

Arabis spp. 

Cistus spp. 

Rodgersia aesculifolia 

Rodgersia pinnata 

Rohdea japonica 

Roscoea purpurea 

Rosa hybrids..bush 

Lychnis coronaria 

Isopogon formosus 

Rhodohypoxis spp. 

Hibiscus syriacus 

Salvia involucrata 

Rosmarinus officinalis 

Prostanthera rotundifolia 

Hypericum 'Rowallane' 

Ficus auriculata 

Wahlenbergia gloriosa 

Oxera pulchella 

Salvia muelleri 

Distictis 'Rivers' 

Osmunda regalis 

Ficus elastica 

127


COMMON NAME 


ruby grass 

Rhynchelytrum neriglume 

rush 

Juncus spp. 

Russell lupines 

Lupinus (Russell hybrids) 

Russian olive 

Elaeagnus angustifolia 

Russian sage 

Perovskia spp. 

rusty leaf fig 

Ficus rubiginosa 

Ryukyu Island palm 

Arenga engleri 

S. California black walnut Juglans californica 

sage (forskaohlei/hians) 

Salvia forskaohlei (hians) 

sage (glechomaefolia) 

Salvia glechomaefolia 

sage (iodantha) 

Salvia iodantha 

sage (jamensis cvs.) 

Salvia X jamensis cvs. 

sage (reptans) 

Salvia reptans 

sage (superba) 

Salvia X superba hybrids & cvs. 

sagebrush 

Artemisia spp. (shrubby) 

sago palm 

Cycas revoluta 

saguaro 

Carnegiea gigantea 

sakaki 

Cleyera japonica 

salal 

Gaultheria shallon 

Salt River mallet 

Eucalyptus sargentii 

saltbush 

Atriplex spp. 

San Clemente Island bush mallow 

Malacothamnus clementinus 

San Diego County viguiera 

Viguiera laciniata 

San Diego mountain mahogany 

Cercocarpus minutiflorus 

San Diego willowy mint 

Monardella linoides ssp. viminea 

San Jose hesper palm 

Brahea brandegeei 

San Miguel Mountain sage 

Salvia munzii 

San Miguel savory 

Satureja chandleri 

sandanqua viburnum 

Viburnum suspensum 

sandwort 

Arenaria montana 

Santa Cruz Island gooseberry 

Ribes thacherianum 

sapphire dragon tree 

Paulownia kawakamii 

Saratoga laurel 

Laurus 'Saratoga' 

Sargent cherry 

Prunus sargentii 

sasanqua camellia 

Camellia sasanqua 

saucer magnolia 

Magnolia X soulangiana 

savory 

Satureja mexicana 

saw leaf zelkova 

Zelkova serrata 

saxifrage 

Saxifraga spp. 

scarlet monardella 

Monardella macrantha 

scarlet oak 

Quercus coccinea 

scarlet red maple 

Acer rubrum 

scarlet sage 

Salvia gesneriflora 

Scotch elm 

Ulmus glabra 

Scotch heather 

Calluna vulgaris 

Scotch moss 

Sagina subulata 'Aurea' 

Scotch pine 

Pinus sylvestris 

screwbean mesquite 

Prosopis pubescens 

sea dahlia 

Coreopsis maritima 

sea foam 

Holodiscus discolor 

sea holly 

Eryngium pandanifolium 

sea holly 

Eryngium variifolium 

sea oats 

Chasmanthium latifolium 

sea pink 

Armeria alliacea 

sea pink 

Armeria maritima 

sea squill 

Urginea maritima 

128


COMMON NAME 

sea urchin tree 

sedge 

self heal 

semiaquilegia 

Senegal date palm 

senna/cassia (odorata) 

senna/cassia (spectabilis/excelsa) 

senna/cassia didymobotrya 

sensitive fern 

Serbian bell flower 

Serbian spruce 

serissa 

Shasta daisy 

shaving brush 

sheild/wood fern 

shell bush 

shell ginger 

Sherwood dwarf abelia 

shiny xylosma 

showy banksia 

showy jasmine 

shrimp plant 

shrub aster 

shrub pincushion 

shrubby cassia 

shrubby dogweed 

Shumard red oak 

Siberian bugloss 

Siberian cypress 

Siberian elm 

Siberian iris 

Siberian wallflower 

sideoats gramma 

sideritis 

Sierra sundrop 

silk oak 

silk tree 

silver buffaloberry 

silver button plant 

silver cassia/senna 

silver dichondra 

silver dollar gum 

silver gimlet 

silver lace vine 

silver lupine 

silver maple 

silver mountain gum 

silver sage 

silver spear 

silver tree 

silver vein creeper 

silver wattle 

silverberry 

silvery yarrow 

Sinaloan blue sage 

single leaf pinyon pine 


Hakea laurina 

Carex (garden spp.) 

Prunella spp. 

Semiaquilegia ecalcarata 

Phoenix reclinata 

Senna odorata (Cassia odorata) 

Senna spectabilis (Cassia excelsa) 

Senna didymobotrya (Cassia didymobotrya) 

Onoclea sensibilis 

Campanula poscharskyana 

Picea omorika 

Serissa foetida 

Leucanthemum X superbum 

Pseudobomax ellipticum 

Dryopteris arguta 

Orthosiphon labiatus 

Alpinia zerumbet 

Abelia 'Sherwoodii' 

Xylosma congestum 

Banksia speciosa 

Jasminum floridum 

Justicia brandegeana 

Felicia fruticosa 

Pterocephalus dumetorum 

Cassia wizlizeni 

Dyssodia acerosa 

Quercus shumardii 

Brunnera macrophylla 

Microbiota decussata 

Ulmus pumila 

Iris spp. 

Erysimum hyeraciifolium 

Bouteloua curtipendula 

Sideritis syriaca 

Calyophus hartwegii 

Grevillea robusta 

Albizia julibrissin 

Shepherdia argentea 

Cotula lineariloba 

Senna phyllodenia (Cassia phyllodenia) 

Dichondra argenta 

Eucalyptus polyanthemos 

Eucalyptus campaspe 

Polygonum aubertii 

Lupinus albifrons 

Acer saccharinum 

Eucalyptus pulverulenta 

Salvia argentea 

Astelia nervosa chathamica 

Leucadendron argenteum 

Parthenocissus henryana 

Acacia dealbata 

Elaeagnus pungens 

Achillea clavennae 

Salvia sinaloensis 

Pinus monophylla 

129


COMMON NAME 

sissoo 

sisysrinchium (convolutum) 

sisysrinchium (striatum) 

sky flower 

sky flower 

slipper flower/slipperwort 

small flowered clematis 

Smith's brush cherry 

Smith's tecoma 

smoke tree 

smoke tree 

smooth Arizona cypress 

snail vine 

snakeweed 

snapdragon vine 

snow in summer 

snowball hydrangea 

snowberry 

snowdrop bush 

snowdrop windflower 

Snowy River wattle 

snowy woodrush 

soapbark tree 

society garlic 

soft muhly 

Soloman's seal 

Sonoma sage 

Sonora cercidium 

Sonoran justicia 

Sonoran palo verde 

sorrel/shamrock 

sour gum/tupelo 

sourwood tree 

South African jasmine 

South African mallow 

southern live oak 

southern magnolia 

southern sword fern 

southwest redbud 

Spanish broom 

Spanish fir 

Spanish oak 

Spanish shawl 

Spanish/Dutch iris 

spathiphyllum 

spear lily 

speedwell 

spicy jatropha 

spiderwort 

spiderwort 

spike sage 

spiny headed mat rush 

spiraea 

spotted deadnettle 

spotted emu bush 

spotted gum 


Dalbergia sissoo 

Sisyrinchium convolutum 

Sisysrinchium striatum 

Duranta erecta (D. repens) 

Thunbergia grandiflora 

Calceolaria spp. 

Clematis pauciflora 

Syzygium smithii 

Tecoma X smithii 

Cotinus coggygria 

Psorothamnus spinosa (Dalea spinosa) 

Cupressus arizonica var.glabra 

Vigna caracalla 

Gutierrezia sarothrae 

Asarina antirriniflora (Maurandya) 

Cerastium tomentosum 

Hydrangea arborescens 

Symphoricarpus albus 

Styrax officinale redivivus 

Anemone sylvestris 

Acacia boormanii 

Luzula nivea 

Quillaja saponaria 

Tulbaghia violacea 

Muhlenbergia pubescens 

Polygonatum odoratum (japonicum) 

Salvia 'Dara's Choice' 

Cercidium 'Sonorae' 

Justicia sonorea 

Cercidium praecox 

Oxalis spp. 

Nyssa sylvatica 

Oxydendrum arboreum 

Jasminum angulare 

Anisodontea X hypomadarum 

Quercus virginiana 

Magnolia grandiflora 

Nephrolepis cordifolia 

Cercis reniformis 

Spartium junceum 

Abies pinsapo 

Quercus texana 

Heterocentron elegans 

Iris spp. 

Spathiphyllum spp. 

Doryanthes palmeri 

Veronica repens 

Jatropha integerrima 

Tradescantia X andersoniana 

Tradescantia pallida 

Salvia confertiflora 

Lomandra longifolia 

Spiraea spp. 

Lamium maculatum 

Eremophila maculata 

Eucalyptus maculata 

130


COMMON NAME 

spring cinquefoil 

spring star flower 

square-stemmed bamboo 

squawbush 

squirrel's foot fern 

St.Johnswort 

staghorn sumac 

stalked bulbine 

standing cypress 

star jasmine 

star lily 

star magnolia 

statice 

statice 

stemless carline thistle 

stenomesson 

Stephan jasmine 

stokes aster 

stone crop 

straw flower 

straw flower 

strawberry 

strawberry guava 

strawberry snowball 

strawberry tree 

Sturt's cassia/senna 

subporosa acacia 

sugar bush 

sugar gum 

sugar maple 

sugar scoop 

summer holly 

summer hyacinth 

summer snow 

summer snowflake 

summersweet 

sun rose 

sutera 

swamp honey-myrtle 

swamp jessamine 

swamp mahogany 

swamp mallee 

swamp paper bark 

swamp sunflower 

swamp weed 

Swan River daisy 

Swedish ivy 

sweet acacia 

sweet bay 

sweet box 

sweet flag 

sweet garlic 

sweet gum 

sweet hakea 

sweet olive/osmanthus 

sweet pea shrub 


Potentilla neumanniana (tabernaemontani) 

Ipheion uniflorum (Tritelia) 

Chimonobambusa quadrangularis 

Rhus trilobata 

Davallia trichomanoides 

Hypericum 'Hidecote' 

Rhus typhina 

Bulbine frutescens 

Ipomopsis rubra 

Trachelospermum jasminoides 

Arthropodium cirrhatum 

Magnolia stellata 

Goniolimon incanum (Limonium speciosum) 

Limonium perezii 

Carlina acaulis 

Stenomesson variegatum 

Jasminum X stephanense 

Stokesia laevis 

Sedum spp. 

Helichrysum bracteatum 

Plecostachys serpyllifolia (Helichrysum) 

Fragaria spp. 

Psidium littorale var. longipes 

Dombeya cacuminum 

Arbutus unedo 

Senna sturtii (Cassia sturtii) 

Acacia subporosa 

Rhus ovata 

Eucalyptus cladocalyx 

Acer saccharum 

Tiarella wherryi 

Arctostaphylos diversiloba (Comarostaphylis diversiloba) 

Galtonia candicans 

Plumbago scandens 

Leucojum aestivum 

Clethra alnifolia 

Halimium lasianthum 

Sutera spp. 

Melaleuca squamea 

Gelsemium rankinii 

Eucalyptus robusta 

Eucalyptus spathulata 

Melaleuca rhaphiophylla 

Helianthus angustifolius 

Selliera radicans 

Brachycome spp. 

Plectranthus spp. 

Acacia farnesiana 

Laurus nobilis 

Sarcococca confusa 

Acorus gramineus 

Tulbaghia fragrans 

Liquidambar styraciflua 

Hakea suaveolens 

Osmanthus spp. 

Polygala X dalmaisiana 

131


COMMON NAME 

sweet sarcococca 

sweet shade 

sweet shade 

sweet vernal grass 

sweet viburnum 

sweet violet 

sweet woodruff 

switch grass 

switch grass 

sword fern 

Sydney golden wattle 

Sykes coral tree 

takil fan palm 

tall aristea 

tall baeckia 

tamarisk 

tanbark oak 

tansy 

tarata 

tarragon/angel's hair etc. 

Tartarian statice 

Tasmanian tree fern 

tatarian honeysuckle 

tawhiwhi 

tea tree 

tea tree 

tea tree 

tea viburnum 

tecate cypress 

tecomanthe 

tenaza 

Texas ebony 

Texas firecracker bush 

Texas mountain laurel 

Texas needle grass 

Texas olive 

Texas red oak 

Texas sage 

Texas sycamore 

thread leaf false aralia 

threadleaf coreopsis 

thrift 

thrift 

throatwart 

thumbergia (mysorensis) 

thunbergia (battiscombei) 

thyme 

thyme honey-myrtle 

ti plant 

tickseed 

tiger grass 

tipu tree 

toad lily 

toadflax 

toadflax 

Tolleson's juniper 


Sarcococca hookerana humilis 

Hymenosporum flavum 

Tetraneuris acaulis (Hymenoxis acaulis) 

Anthoxanthum odoratum 

Viburnum odoratissimum 

Viola odorata 

Galium odoratum 

Panicum virgatum cvs. 

Panicum( native spp.) 

Polystichum californicum 

Acacia longifolia 

Erythrina X sykesii 

Trachycarpus takil 

Aristea major 

Baeckea virgata 

Tamarix spp. 

Lithocarpus densiflorus 

Tanacetum haradjanii 

Pittosporum eugenioides 

Artemisia spp. (herbaceous) 

Gonilimon tataricum (Limonium tataricum) 

Dicksonia antarctica 

Lonicera tatarica 

Pittosporum tenuifolium 

Leptospermum polygalifolium 

Leptospermum rotundifolium 

Leptospermum rupestre (humifusum) 

Viburnum setigerum 

Cupressus guadalupensis forbesii 

Tecomanthe speciosa 

Pithecellobium pallens 

Pithecellobium flexicaule 

Hamelia patens 

Sophora secundiflora 

Nassella tenuissima 

Cordia boissieri 

Quercus buckleyi 

Salvia coccinea 

Platanus occidentalis 'Glabrata' 

Schefflera elegantissima (Dizygotheca) 

Coreopsis verticilata cvs. 

Armeria caespitosa (A. juniperifolia) 

Armeria setacea 

Trachelium caeruleum 

Thunbergia mysorensis 

Thunbergia battiscombei 

Thymus spp. 

Melaleuca thymifolia 

Cordyline terminalis 

Bidens triplinervia 

Thysanolaena maxima 

Tipuana tipu 

Tricyrtis hirta 

Linaria purpurea 

Linaria supina 

Juniperus scopulorum'Tolleson' 

132


COMMON NAME 

toog 

torch cactus 

Torrey pine 

totara 

totem poles (lilac melaleuca) 

tower of jewels 

toyon 

trailing daisy 

trailing indigo bush 

trailing lantana 

trailing rosemary 

Transvaal daisy 

tree banksia 

tree dahlia 

tree euphorbia 

tree ivy 

tree mallow 

tree of heaven 

tree philodendron 

treebine 

triangle palm 

triangleleaf bursage 

trident maple 

trinidad flame bush 

tritonia 

trixis 

true myrtle 

trumpet creeper 

trumpet honeysuckle 

tuberose 

tufted (white) evening primrose 

tufted hairgrass 

tulip tree 

tulipwood 

Turk's cap 

turpentine bush 

Turutu 

twinspur 

twisted acacia 

umbrella bamboo 

umbrella catalpa 

umbrella plant/Indian rhubarb 

umbrella sedge/papyrus 

valley oak 

Vancouver gold genista 

veitch magnolia 

velvet centaurea 

velvet honeysuckle 

velvet mesquite 

velvet slipper 

verbena (bonariensis) 

verde vista coprosma 

veronica 

veronica/speedwell 

vervian 

viburnum (rhytidophylloides) 


Bischofia javanica 

Echinopsis spp. (Trichocereus spp.) 

Pinus torreyana 

Podocarpus totara 

Melaleuca decussata 

Echium wildpretii 

Heteromeles arbutifolia 

Wedelia trilobata 

Dalea greggii 

Lantana montevidensis (sellowiana) 

Rosemarinus 'Prostratus' 

Gerbera jamesonii 

Banksia integrifolia 

Dahlia imperialis 

Euphorbia lambii 

X Fatshedera lizei 

Lavatera assurgentiflora 

Ailanthus altissima 

Philodendron bipinnatifidum (selloum) 

Cissus trifoliata 

Neodypsis decaryi 

Ambrosia deltoidea 

Acer buergerianum 

Calliandra tweedii 

Tritonia spp. 

Trixis californica 

Myrtus communis 

Campsis spp. 

Lonicera sempervirens 

Polyanthes tuberosa 

Oenothera caespitosa 

Deschampsia caespitosa 

Liriodendron tulipifera 

Harpullia arborea 

Malvaviscus arboreus 

Ericameria laricifolia (Haplopappus) 

Dianella intermedia 

Diascia spp. 

Acacia schaffneri 

Thamnocalamus spathaceus (Fargesia murieliae) 

Catalpa bungei 

Darmera peltata 

Cyperis spp. 

Quercus lobata 

Genista pilosa (Vancouver Gold) 

Magnolia X veitchii 

Centaurea gymnocarpa 

Dicliptera suberecta 

Prosopis velutina 

Sinningia tubiflora 

Verbena bonariensis 

Coprosma petriei 'Verde vista' 

Veronica spp. 

Parahebe spp. 

Verbena rigida 

Viburnum X rhytidophylloides 

133


COMMON NAME 

victorian box 

victorian dogwood 

villebrunea 

vine maple 

vining bluebell 

violet (japonica) 

violet trumpet vine 

violet tubeflower 

violet westringia 

Virginia creeper 

wallflower 

wallflower 

wallflower 

wallflower 

wallflower 

wandering Jew 

waratah 

Warley rose stone cress 

water birch 

water dropwort 

watsonia 

Waverly sage 

Wax begonia 

weeping acacia 

weeping bottle brush 

weeping Chinese banyan 

weigelia 

Wenlock beauty wallflower 

western Australia coral pea 

western catalpa 

western cottonwood 

western dog violet 

western dogwood 

western hackberry 

western hazelnut 

western redbud 

western spice bush 

western sword fern 

western virgin's bower 

westringia (longifolia) 

white alder 

white ash 

white barked Himalayan birch 

white breath of heaven 

white bursage 

white clover 

white Florida anise-tree 

white floss silk tree 

white flowering currant 

white fringe tree 

white ginger lily 

white ironbark 

white mulberry 

white rock rose 

white sage 

white sapote 


Pittosporum undulatum 

Prostanthera lasianthos 

Villebrunea pedunculata 

Acer circinatum 

Sollya parvifolia 

Viola japonica 

Clytostoma callistigioides 

Iochroma cyanea 

Westringia glabra 

Parthenocissus quinquefolia 

Erysimum cheiri (Cherianthus cheiri) 

Erysimum helveticum 

Erysimum linifolium 

Erysimum menziesii 

Erysimum pulchellum 

Tradescantia fluminensis 

Telopea speciosissima 

Aethionema armenium 'Warley Rose' 

Betula fontinalis (occidentalis) 

Oenanthe javanica 

Watsonia spp. 

Salvia 'Waverly' 

Begonia semperflorens 

Acacia pendula 

Callistemon viminalis 

Ficus benjamina 

Weigela florida 

Erysimum 'Wenlock Beauty' 

Hardenbergia comptoniana 

Catalpa speciosa 

Populus fremontii 

Viola adunca 

Cornus nuttallii 

Celtis reticulata 

Corylus cornuta californica 

Cercis occidentalis 

Calycanthus occidentalis 

Polystichum munitum 

Clematis ligusticifolia 

Westringia longifolia 

Alnus rhombifolia 

Fraxinus americana 

Betula utilis var. jaquemontii 

Coleonema album 

Ambrosia dumosa 

Trifolium repens 

Illicium floridanum 'Alba' 

Chorisia insignis 

Ribes indecorum 

Chionanthus virginicus 

Hedychium coronarium 

Eucalyptus leucoxylon 

Morus alba 

Helianthemum appenium 

Salvia apiana 

Casimiroa edulis 

134


COMMON NAME 

white striped dwarf bamboo 

white weigela 

whitethorn acacia 

whorlflower 

wild ginger 

wild hyacinth 

wild mock orange 

wild rye 

wild rye 

willow 

willow acacia 

willow pittosporum 

Wilson holly 

Wilson melaleuca 

windmill palm 

winter blooming bergenia 

winter creeper 

winter daphne 

winter hazel 

winter jasmine 

winter sweet pea 

winterberry 

winter's bark 

wintersweet 

wire-netting bush 

wishbone bush 

wisteria 

wolfberry 

wong-lan 

wonga wonga vine 

wood fern 

woolly bush 

woolly bush 

woolly butterfly bush 

woolly yarrow 

woolly/mountain blue curls 

wooly senna 

wrinkled agastache 

Wynyabbie gem westringia 

yaupon 

Yeddo hawthorne 

yellow archangel 

yellow bells 

yellow ginger 

yellow mallow 

yellow oleander 

yellow orchid vine 

yellow penstemmon 

yellow plume flower 

yellow trumpet vine 

yellow waxbells 

yellow waxbells 

yellow wood 

yerba buena 

yerba mansa 

yesterday today and tomorrow 


Sasaella masamuniana albostriata 

Weigela coraeensis 

Acacia constricta 

Morina longifolia 

Asarum caudadum 

Dichelostemma capitatum 

Philadelphus lewisii californicus 

Elymus spp. (also see Leymus spp.) 

Leymus spp. (also see Elymus spp.) 

Salix spp. 

Acacia salicina 

Pittosporum phillyraeoides 

Ilex X altaclarensis 'Wilsonii' 

Melaleuca wilsonii 

Trachycarpus fortunei 

Bergenia crassifolia 

Euonymus fortunei radicans 

Daphne odora 

Corylopsis spicata 

Jasminum nudiflorum 

Swainsonia galegifolia 

Ilex verticillata 

Drimys winteri 

Chimonanthus praecox 

Corokia cotoneaster 

Mirabilis california 

Wisteria spp. 

Lycium fremontii 

Michelia doltsopa 

Pandorea pandorana 

Dryopteris erythrosora 

Adenanthos drummondii 

Adenanthos sericea 

Buddleja marrubiifolia 

Achillea tomentosa 

Trichostema lanatum 

Senna multiglandulosa (Cassia tomentosa) 

Agastache rugosa 

Westringia 'Wynyabbie Gem' 

Ilex vomitoria 

Rhaphiolepis umbellata 

Lamiastrum galeobdolon 

Tecoma stans 

Hedychium flavescens 

Pavonia praemorsa 

Thevetia peruviana 

Mascagnia macroptera 

Keckiella antirhinnoides 

Justicia aurea 

Anemopaegma chamberlaynii 

Kirengeshoma koreana 

Kirengeshoma palmata 

Podocarpus latifolius 

Satureja douglasii 

Anemopsis californica 

Brunfelsia pauciflora 

135


COMMON NAME 

Yew (media cvs.) 

yew pine 

York gum 

yucca 

zaluzinskya 

zebra rush 

zephyr flower 

zexmenia 


Taxus X media cvs. 

Podocarpus macrophyllus 

Eucalyptus loxophleba 

Yucca spp. 

Zaluzianskya katherinae 

Schoenoplectus lacustris var.tabernaemontani 

Zephryranthes spp. 

Zexmenia hispida 

136

Turfgrasses 

____________________________________________________________________ 

Grass Type Irrigation Requirements 

____________________________________________________________________ 

annual bluegrass cool season 80% of ETo 

____________________________________________________________________ 

annual ryegrass cool season 80% of ETo 

____________________________________________________________________ 

Bermudagrass warm season 60% of ETo 

____________________________________________________________________ 

colonial bentgrass cool season 80% of ETo 

____________________________________________________________________ 

creeping bentgrass cool season 80% of ETo 

____________________________________________________________________ 

hard fescue cool season 80% of ETo 

____________________________________________________________________ 

highland bentgrass cool season 80% of ETo 

____________________________________________________________________ 

Kentucky bluegrass cool season 80% of ETo 

____________________________________________________________________ 

kikuyugrass warm season 60% of ETo 

____________________________________________________________________ 

meadow fescue cool season 80% of ETo 

____________________________________________________________________ 

perennial ryegrass cool season 80% of ETo 

____________________________________________________________________ 

red fescue cool season 80% of ETo 

____________________________________________________________________ 

rough-stalked bluegrass cool season 80% of ETo 

____________________________________________________________________ 

seashore paspalum warm season 60% of ETo 

____________________________________________________________________ 

St. Augustinegrass warm season 60% of ETo 

_________________________________________________________________ 

tall fescue cool season 80% of ETo 

zoysiagrass warm season 60% of ETo 

From: University of California ANR publication 24191, Turfgrass Evapotranspiration Map, Central Coast of California. 

137

Appendix A— 

Reference 

Evapotranspiration 

Values for Selected 

Locations in California 

1. Variation in actual ETo 

totals for a month. From 

year to year the actual 

amount of evaporation 

may be substantially 

different than the historical 

average. For example, 

the historical average 

ETo for August in Sacramento is 7.75 

inches. If the summer was particularly cool, 

however, the actual value may be 25% less than 

average, or about 5.8 inches. Conversely, the 

actual amount may be substantially greater during 

a very hot summer. Adjustments to reflect 

actual ETo conditions will be appropriate in some 

years. 

Table 1 gives monthly average values for reference 

evapotranspiration (ETo) in selected California locations. 

All values are reported in inches per day. 

To calculate inches per month, select a location in 

the column on the left, then select a month and read 

the value corresponding to the location. Multiply 

the column value times the number of days in the 

month. For example, reference evapotranspiration 

in Sacramento for the month of August is 7.75 inches 

(.25 x 31 = 7.75). 

The numbers in Appendix 

A are normal year (historical) 

averages, derived from 

several years of data for the 

month and location. Adjustments 

to normal year 

values may be needed to account 

for: 

2. Variation in location. Adjustments in ETo may 

be needed for the location of the landscape planting. 

The climatic conditions at the ETo measuring 

site may be substantially different than those 

at the landscape site. For example, San Francisco 

does not have a CIMIS station. CIMIS 

stations closest to San Francisco are in Marin 

County and San Mateo County. To use data from 

either Marin or San Mateo for San Francisco, a 

downward adjustment in ETo would be needed 

since both locations are considerably warmer 

than San Francisco. It is important to know 

Reference evapotranspiration (ETo) values are collected at various sites in California. The ETo site 

closest to your location may or may not have climatic conditions similar to your site. If not, then 

adjusments in ETo values will be needed. For example, using Marin County or San Mateo County 

data for San Francisco will likely produce an overestimate of landscape water needs. 

139

where ETo measurements are being taken and 

then decide whether meaningful differences exist 

between your location and the measurement 

location. The assistance of a qualified 

biometeoroligist is recommended if adjustments 

for location are needed. 

Appendix A—Table 1 

Reference Evapotranspiration Rates for Selected Cities* 

Daily Average Reference Evapotranspiration by ETo Zone (inches per day) 

EToZone City Jan Feb Mar Apr May June July Aug Sept Oct Nov Dec 

1 Santa Monica 0.03 0.05 0.08 0.11 0.13 0.15 0.15 0.13 0.11 0.08 0.04 0.02 

2 Santa Cruz 0.04 0.06 0.10 0.13 0.15 0.17 0.16 0.15 0.13 0.09 0.06 0.04 

3 Monterey/Salinas 0.06 0.08 0.12 0.16 0.17 0.19 0.18 0.17 0.14 0.11 0.08 0.06 

4 San Diego 0.06 0.08 0.11 0.15 0.17 0.19 0.19 0.18 0.15 0.11 0.08 0.06 

5 Santa Rosa 0.03 0.06 0.09 0.14 0.18 0.21 0.21 0.19 0.15 0.10 0.05 0.03 

6 Los Angeles 0.06 0.08 0.11 0.16 0.18 0.21 0.21 0.20 0.16 0.12 0.08 0.06 

7 Alturas 0.02 0.05 0.08 0.13 0.17 0.21 0.24 0.21 0.16 0.09 0.04 0.02 

8 San Jose 0.04 0.06 0.11 0.16 0.20 0.23 0.24 0.21 0.17 0.11 0.06 0.03 

9 San Bernardino 

Pasadena 0.07 0.10 0.13 0.17 0.19 0.22 0.24 0.22 0.19 0.13 0.09 0.06 

10 Paicines 0.03 0.06 0.10 0.15 0.19 0.24 0.26 0.23 0.17 0.10 0.05 0.03 

11 Sonora 0.05 0.08 0.10 0.15 0.19 0.24 0.26 0.24 0.19 0.12 0.07 0.05 

12 Fresno 0.04 0.07 0.11 0.17 0.22 0.26 0.26 0.23 0.18 0.12 0.06 0.03 

13 Quincy 0.04 0.07 0.10 0.16 0.21 0.26 0.29 0.25 0.19 0.12 0.06 0.03 

14 Sacramento 0.05 0.08 0.12 0.17 0.22 0.26 0.28 0.25 0.19 0.13 0.07 0.05 

15 Bakersfield 0.04 0.08 0.12 0.19 0.24 0.27 0.28 0.25 0.19 0.13 0.07 0.04 

16 Hanford 0.05 0.09 0.13 0.19 0.25 0.29 0.30 0.27 0.21 0.14 0.08 0.05 

17 Needles 0.06 0.10 0.15 0.20 0.26 0.30 0.32 0.28 0.22 0.14 0.09 0.06 

18 Palm Springs 0.08 0.12 0.17 0.23 0.28 0.32 0.31 0.28 0.23 0.16 0.10 0.07 

* For comprehensive descriptions of each zone and to locate your region in a zone, see the California Irrigation 

Management Information System (CIMIS) color map opposite this page. 

140

California Irrigation Management Information System (CIMIS) 

REFERENCE EVAPOTRANSPIRATION ZONES 

Reference EvapoTranspiration (ETo) Zones 

1 

2 

3 

4 

5 

6 

7 

8 

COASTAL PLAINS HEAVY FOG BELT lowest 

ETo in California, characterized by dense fog 

COASTAL MIXED FOG AREA less fog and 

higher ETo than zone 1 

COASTAL VALLEYS & PLAINS & NORTH 

COAST MOUNTAINS more sunlight than zone 2 

SOUTH COAST INLAND PLAINS & 

MOUNTAINS NORTH OF SAN FRANCISCO 

more sunlight and higher summer ETo than 

zone 3 

NORTHERN INLAND VALLEYS valleys north of 

San Francisco 

UPLAND CENTRAL COAST & LOS ANGELES 

BASIN higher elevation coastal areas 

NORTHEASTERN PLAINS 

INLAND SAN FRANCISCO BAY AREA inland 

area near San Francisco with some marine 

influence 

9 

10 

11 

12 

13 

14 

15 

16 

17 

18 

SOUTH COAST MARINE TO DESERT 

TRANSITION inland area between marine & 

desert climates 

NORTH CENTRAL PLATEAU & CENTRAL 

COAST RANGE cool, high elevation areas with 

strong summer sunlight; zone has limited climate 

data & the zones selection is somewhat 

subjective 

CENTRAL SIERRA NEVADA mountain valleys 

east of Sacramento with some influence from 

delta breeze in summer 

EAST SIDE SACRAMENTO-SAN JOAQUIN 

VALLEY low winter & high summer ETo with 

slightly lower ETo than zone 14 

NORTHERN SIERRA NEVADA northern Sierra 

Nevada mountain valleys with less marine 

influence than zone 11 

MID-CENTRAL VALLEY, SOUTHERN SIERRA 

NEVADA, TEHACHAPI & HIGH DESERT 

MOUNTAINS high summer sunshine and wind 

in some locations 

NORTHERN & SOUTHERN SAN JOAQUIN 

VALLEY slightly lower winter ETo due to fog and 

slightly high summer ETo than zones 12 & 14 

WESTSIDE SAN JOAQUIN VALLEY & 

MOUNTAINS EAST & WEST OF IMPERIAL 

VALLEY 

HIGH DESERT VALLEYS valleys in the high 

desert near Nevada and Arizona 

IMPERIAL VALLEY, DEATH VALLEY & PALO 

VERDE low desert areas with high sunlight & 

considerable heat advection 

141

Appendix A—Table 2 

Calculations of Species Water Needs for July for Several Locations in California 

Listed are normal year ETo values 1 for July and three categories of water needs. Select the appropriate 

location and water need category. Look down the column to find the estimated water need. This was 

calculated by multiplying ETo x a water need category (low, medium or high). For example, for Los 

Angeles in July, the normal year ETo = 6.5 inches. For a planting in the medium category, (0.4 - 0.6) the 

estimated water need ranges from 2.6 to 3.9 inches. 

Estimated species water needs (inches per month) 2 for JULY 

ETo WUCOLS REGION ETo LOW MEDIUM HIGH 

Zones 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 

NORTH CENTRAL 

4 Novato 5.8 0.6 1.1 1.7 2.3 2.9 3.4 4.0 4.6 5.2 

1, 2 San Francisco 4.6-4.9 0.5 1.0 1.4 1.9 2.4 2.9 3.4 3.9 4.4 

8 Concord 7.4 0.7 1.4 2.2 2.9 3.7 4.4 5.1 5.9 6.6 

8 San Jose 7.4 0.7 1.4 2.2 2.9 3.7 4.4 5.1 5.9 6.6 

3 Monterey 5.5 0.5 1.0 1.6 2.2 2.7 3.3 3.8 4.4 4.9 

6 San Luis Obispo 6.5 0.6 1.3 1.9 2.6 3.2 3.9 4.5 5.2 5.8 

CENTRAL VALLEY 

14 Auburn 8.6 0.9 1.7 2.5 3.4 4.3 5.1 6.0 6.8 7.7 

14 Sacramento 8.6 0.9 1.7 2.5 3.4 4.3 5.1 6.0 6.8 7.7 

12 Modesto/Stockton 8.0 0.8 1.6 2.4 3.2 4.0 4.8 5.6 6.4 7.4 

12 Fresno 8.0 0.8 1.6 2.4 3.2 4.0 4.8 5.6 6.4 7.4 

15 Bakersfield 8.6 0.9 1.7 2.5 3.4 4.3 5.1 6.0 6.8 7.7 

14 Redding 8.6 0.9 1.7 2.5 3.4 4.3 5.1 6.0 6.8 7.7 

SOUTH COASTAL 

4 Santa Barbara 5.8 0.6 1.1 1.7 2.3 2.9 3.4 4.0 4.6 5.2 

4 Ventura 5.8 0.6 1.1 1.7 2.3 2.9 3.4 4.0 4.6 5.2 

6 Los Angeles 6.5 0.6 1.3 1.9 2.6 3.2 3.9 4.5 5.2 5.8 

1, 2 Laguna Beach 4.7-4.9 0.5 1.0 1.4 1.9 2.4 2.9 3.4 3.9 4.4 

4 San Diego 5.8 0.6 1.1 1.7 2.3 2.9 3.4 4.0 4.6 5.2 

SOUTH INLAND VALLEY 

9 San Fernando 7.4 0.7 1.4 2.2 2.9 3.7 4.4 5.1 5.9 6.6 

9 Pasadena 7.4 0.7 1.4 2.2 2.9 3.7 4.4 5.1 5.9 6.6 

9 Riverside 7.4 0.7 1.4 2.2 2.9 3.7 4.4 5.1 5.9 6.6 

9 Ramona 7.4 0.7 1.4 2.2 2.9 3.7 4.4 5.1 5.9 6.6 

9 San Bernardino 7.4 0.7 1.4 2.2 2.9 3.7 4.4 5.1 5.9 6.6 

HIGH DESERT 

17 Palmdale 9.9 1.0 1.9 2.9 3.9 4.9 5.9 6.9 7.9 8.9 

17 Lancaster 9.9 1.0 1.9 2.9 3.9 4.9 5.9 6.9 7.9 8.9 

17 Victorville 9.9 1.0 1.9 2.9 3.9 4.9 5.9 6.9 7.9 8.9 

17 Bishop 9.9 1.0 1.9 2.9 3.9 4.9 5.9 6.9 7.9 8.9 

17 Independence 9.9 1.0 1.9 2.9 3.9 4.9 5.9 6.9 7.9 8.9 

LOW DESERT 

18 Palm Springs 9.6 1.0 1.9 2.8 3.8 4.8 5.7 6.7 7.6 8.6 

18 Coachella 9.6 1.0 1.9 2.8 3.8 4.8 5.7 6.7 7.6 8.6 

18 Needles 9.6 1.0 1.9 2.8 3.8 4.8 5.7 6.7 7.6 8.6 

18 El Centro 9.6 1.0 1.9 2.8 3.8 4.8 5.7 6.7 7.6 8.6 

1. Normal year values and zones are derived from the California Irrigation Management Information System (CIMIS) Reference 

Evapotranspiration Map, 1999. 

2. Please note; these values are not adjusted for irrigation efficiency. 

142

Appendix B— 

Invasive Species 

Certain species, if grown adjacent to wildland areas, 

have the ability to “invade” native habitats to 

the detriment of the native species. Others cause 

problems in managed landscapes. Species of both 

types are listed here. It is incumbent on landscape 

architects, designers, and managers to learn which 

plants are considered to be invasive, and use appropriate 

caution in their use. 

Invasive species are indicated on the list by ☹☹, 

or ☹. 

Examples: 

☹☹ Arundo donax 

Considered an important wildland weed (can 

displace native species in natural communities 

in one or more regions). 

☹ 

Acacia decurrens 

Considered a wildland weed of secondary importance, 

or is potentially invasive, or is a species 

which is limited to one region, landscaped 

areas or roadsides. 

☹☹ Genista spp. 

NOT ALL Genista species are considered invasive. 

Refer to “Notes on Invasive Species” 

for information about Genista monspessulanus 

French broom. 

Notes on Invasive Species 

Acacia baileyana—mainly near habitations 

Acacia dealbata—Northern coastal to southern inland 

regions 

Acacia decurrens—Northern coastal 

Acacia longifolia—Minor threat along coast 

Acacia melanoxylon—Northern coastal and inland to 

southern coastal 

Achillea millefolium—Coastal and inland areas in moist 

places 

Ailanthus altissima—Urban and natural areas around the 

world 

Albezia distachya—Coastal areas 

Aptenia cordifolia ‘Red Apple’—Coastal zones, mainly 

southern 

Arctotheca calendula—Northern and southern coastal 

bluffs, foothills 

Arundo donax—All regions in moist areas, seasonal water 

courses 

Atriplex glauca—Southern coastal foothills 

Altriplex semibaccata - Coastal to inland areas 

Briza media - Grasslands 

Carpobrotus edulis —Coastal and inland regional throughout 

California 

Carpobrotus chilensis — Coastal and inland regional 

throughout California 

Centranthus ruber—Coastal, inland and foothill regions 

throughout California 

Cistus ladanifer—coastal sage scrub and chaparral 

Coprosma repens—Only coastal 

Cordyline australis—Only coastal 

Cortaderia sellowana—Coastal regions, dunes, scrub and 

Monterey pine forest 

Cotoneaster pannosus—Disturbed sites, many communities, 

central and northern coast 

Crataegus monogyna—Central and northern coast 

Cupressus macrocarpa—Northern coastal 

Cytisus canariensis—Foothill regions, northern California 

and Central Valley 

Cytisus racemosus—Foothill regions, northern California 

and Central Valley 

Cytisus scoparius—Coastal scrub, oak woodland 

Cytisus striatus—Coastal scrub, oak woodland 

Delosperma spp. —Potential threat on coast 

Duchesnia indica—Potential threat on coast 

Echium candicans (fastuosum)—Coastal 

Elaeagnus angustifolia—interior riparian areas 

Erica lusitanica—possible threat to wildlands 

Eucalyptus camaldulensis—Southern coastal canyons and 

foothills 

Eucalyptus globulus—Coastal canyons and foothills, 

riparian areas 

Eucalyptus pulverulenta—Southern coastal 

Ficus carica—Central Valley, south coastal and Channel 

Islands riparian woodlands 

Genista monspessulanus—Coastal scrub, oak woodland 

143

Hedera canariensis—Coastal and inland regions in moist 

and shady places 

Hedera helix—Coastal and inland regions in moist and 

shady places 

Helichrysum petiolare—north coastal scrub 

Ilex aquifolium—Coastal forests 

Imperata cylindrica, I brasiliensis—on federal noxious 

weed list 

Juncus spp.—potential to naturalize moist areas 

Ligustrum lucidum—Mendocino coast 

Limonium perezii—Southern coastal beaches and bluffs 

Lonicera japonica ‘Halliana’—Coastal and inland regions; 

moist, shady places 

Lotus corniculatus—Roadside weed 

Lupinus arboreus—North coast dunes 

Lysimachia nummularia—widely naturalized in other 

states, not in CA to date 

Malephora crocea—south coast bluffs, margins of wetlands 

Melaleuca viridifolia (quinqueneveria)—severe problem in 

Florida wetlands, not in CA to date 

Mentha pulegium—invades Santa Rosa Plain (Sonoma 

County) 

Myoporum laetum—Northern and southern coastal foothills 

Myosotis spp.—Coastal forests 

Nereum oleander—Riparian areas 

Oenanthe javanica—potential to naturalize in damp 

habitats 

Olea europaea—Southern coastal and inland foothills 

Pennisetum setaceum—All dry climate regions, grasslands, 

desert canyons 

Phalaris aquatica—coastal sites with moist soil 

Phyla nodiflora—Wet places, vernal pools 

Pinus pinaster—Sparingly naturalized central coast 

Pinus pinea—Sparingly naturalized central coast 

Pinus radiata—Central and northern coastal 

Pyracantha spp.—Central coastal 

Robinia pseudoacacia—Northern valleys and foothills to 

southern mountains and foothills 

Sapium sebiferum—severe problem in Gulf coast wetlands, 

bottomland forests, beginning to appear in CA in 

wetlands in Yolo county and along the American River 

near Sacramento 

Schinus mole—Coastal canyons and foothills statewide 

Schinus terebinthifolius—Coastal lowlands, wet places 

Spartium junceum—Coastal scrub, oak woodlands 

Tamarix chinensis, T gallica, T parviflora, T ramosissima 

(pendantra)—Coastal through desert riparian areas 

Tropaeolum majus —Moist coastal regions 

Vinca major—Riparian areas, oak woodland, mostly 

coastal 

Watsonia bulbillifera—North coast 

Watsonia marginata—North coast 

Zantedeschia aethiopica—Coastal streams 

144

Appendix C— 

Glossary 

Acre-foot 

The amount of water which covers an acre (43,560 ft. 2 ) 

to the depth of one foot (12 inches). One acre-foot 

equals 325,850 gallons. 

CIMIS 

California Irrigation Management Information System. 

A network of weather stations located around 

the state which collects reference evapotranspiration 

data. The network is managed by the California 

Department of Water Resources. 

Conversion Factor (0.62 gallons/ft. 2-inch) 

Used to convert water volume from inches per unit 

area to gallons per unit area. There are 0.62 gallons 

in a square foot-inch. 

Crop Coefficient (Kc) 

Fraction of water lost from the crop relative to reference 

evapotranspiration. 

Crop Evapotranspiration (ETo) 

Water loss from a crop. 

Vegetation Density 

An evaluation of vegetation surface area per unit 

volume taking into consideration factors such as tree 

canopy cover and tiers of vegetation. 

Density Factor (kd) 

One of three factors used to generate a landscape 

coefficient. Adjusts the landscape coefficient to account 

for the effect of vegetation density on water 

loss from a hydrozone. 

ET 

Evapotranspiration. The sum of water losses 

through evaporation (E) from the soil and transpiration 

(T) from the plant. 

ETo 

Reference Evapotranspiration. The approximation 

of water loss from a field of 4-to-7-inch-tall coolseason 

grass that is not water stressed. ETo is measured 

at CIMIS weather stations in various locations 

around the state. 

ETL 

Estimated water needs of the landscape. Calculated 

by multiplying the landscape coefficient (KL) by 

Reference Evapotranspiration (ETo). 

Hydrozone 

A portion of a landscaped area having plants with 

similar water needs that are served by one irrigation 

valve or set of valves with the same schedule. 


A measure of the portion of the total applied irrigation 

water beneficially used (primarily to satisfy 

plant water needs). Losses (non-beneficial water 

use) include unused runoff and evaporation from 

wet soil surfaces. 

Landscape Coefficient (KL) 

The functional equivalent of the crop coefficient. 

Used for estimating water needs from landscape 

plantings. Landscape coefficient = species factor x 

microclimate factor x density factor. 

Microclimates 

Areas having different environmental conditions 

within a climatic zone. 

145

Microclimate Factor (kmc) 



for the effect of microclimate on water loss 

from a hydrozone. 

Species Factor (ks) 



for water loss from a hydrozone due to the 

plant species composition. 

Square foot-inch 

The amount of water which covers one square foot 

of area to the depth of one inch. One square footinch 

equals 0.62 gallons. 

TWA 

Total water applied. An estimate of the total amount 

of water to apply to a landscape planting. Calculated 

by dividing ETL (estimated water needs of the 

planting) by IE (irrigation efficiency). 

WUCOLS 

Water Use Classification of Landscape Species. A 

Guide to the Water Needs of Landscape Plants. 

146

Appendix D— 

Additional Resources 

Griffiths, M., 1994, Index of Garden Plants, Royal 

Horticultural Society, Timber Press, Portland, 

OR. 

References 

Cal Poly Irrigation Training and Research Center, 

Landscape Water Manager, (irrigation management 

software) California Polytechnic State University, 

San Luis Obispo, CA. 

Clebsch, B., 1997, A Book of Salvias, Sages for 

Every Garden, Timber Press, Portland, OR. 

Coate, B., 1990, Water-Conserving Plants and 

Landscapes for the Bay Area, East Bay Municipal 

Utility District, Alamo, CA. 

Cornell University Bailey Hortorium Staff, 1976, 

Hortus Third, MacMillan Publishing Co., Inc. 

Costello, L.R., D. Thomas, and J. DeVries, 1996, 

“Plant water loss in a shaded environment: a 

pilot study.” J. of Arboriculture 22(2):106-108. 

Evans, M. and J. Bohn, Tree of Life Wholesale 

Nursery Catalog 1998, San Juan Capistrano. 

Feldman F., and Fogle C. E., 1989, Sunset 

Waterwise Gardening, Lane Publishing Company, 

Menlo Park, CA. 

Gibeault, V. A., J. L. Meyer, R. Autio, R. Strohman, 

1986, “Turfgrass Alternatives With Low Water 

Needs.” California Agriculture, 40 (7, 8):19-20. 

Greenlee, J., 1992, The Encyclopedia of Ornamental 

Grasses, Rodale Press, Emmaus, PA. 

Harris, R.W., J. R. Clark, and N. P. Matheny, 1999, 

Arboriculture: The Integrated Management 

of Landscape Trees, Shrubs and Vines, 3rd Edition. 

Prentice Hall, Englewood Cliffs, NJ. 

Hartin, J., Meyer, J., 1991 Research conducted at 

U.C. South Coast Field Station on four landscape 

tree species. U.C. Cooperative Extension, San 

Bernardino County. (personal communication). 

Hartin, J., Pittenger, D., 1988, Suggested Landscape 

Trees For the San Bernardino Valley, University 

of California Cooperative Extension San 

Bernardino and Riverside Counties. 

Johnson, E. and Scott M., 1993, How to Grow the 

Wildflowers, Ironwood Press, Tucson. 

Johnson, E. and Scott M., 1993, The Low Water 

Flower Gardener, Ironwood Press, Tucson. 

Keator, G., 1990, Complete Garden Guide to the 

Native Perennials of California, Chronicle 

Books, San Francisco. 

Keator, G., 1994, Complete Garden Guide to the 

Native Shrubs of California, Chronicle Books, 

San Francisco. 

Levitt, D. G., J. R. Simpson, J. L. Tipton, 1995, 

Water Use of Two Landscape Trees in Tucson 

Arizona, Journal American Society of Horticultural 

Science, 120(3):409-416. 

147

Lindsey, P. and N. Bassuk, 1991,“Specifying soil 

volumes to meet the water needs of mature urban 

street trees in containers.” J. Arboric. 17 

(6):141-149. 

Schwankl, L., Hanson, B., Prichard T., 1993, Low- 

Volume Irrigation: a Handbook for Water 

Managers, University of California Irrigation 

Program, University of California, Davis. 

Macoboy, S., 1988, What Flower is That? Portland 

House, New York, NY. 

MacNair, J., Estimating Water Use and Irrigation 

Schedules for Ornamental Landscape, presented 

at the 1992 Northern California Zeriscape 

Conference. 

Shuler, C., 1993, Low Water Use Plants for California 

and the Southwest, Fisher Books, Tucson. 

Smith, M.N., 1997, A Guide to Ornamental Plants 

for Coastal California with Cultural Notes, 

Suncrest Nurseries Inc., Watsonville, CA. 

Metcalf, L. J., 1987, The Cultivation of New 

Zealand Trees and Shrubs, Reed Methuen Publishers 

Ltd., Aukland. 

Meyer, J. L. and V. A. Gibeault, 1986, “Turfgrass 

Performance Under Reduced Irrigation.” California 

Agriculture, 40 (7, 8):19-20. 

Ottesen, C., 1989, Ornamental Grasses, the Amber 

Wave, McGraw Hill, NY. 

Perry, R., 1992, Trees and Shrubs for Dry California 

Landscapes, Land Design Publishing, 

Claremont CA. 

Staats, D. and J.E. Klett, 1993, “Evaluation of water 

conservation potential of non-turf 

groundcovers versus Kentucky bluegrass.” 

Colorado State University, Department of Horticulture. 

Fort Collins, CO. (unpublished). 

Sunset Book and Magazine Editors, 1998, Sunset 

Western Garden Book, Menlo Park, CA. 

Turner, R.J., Wasson, E., Ed., 1997, Botanica, Mynah, 

New York. 

Woods, C., 1992, Encyclopedia of Perennials, a 

Gardener’s Guide, Facts on File, New York. 

Pittenger, D.R, D.R. Hodel and D. A. Shaw, 1990, 

“Relative water requirements of six groundcover 

species.” HortScience, 25 (9): 1985. (Abstr.) . 

Vermeulen, N., 1998, Cacti, Rebo Productions, 

Lisse, The Netherlands. 

Sachs, R. M., 1991, “Stress-adapted Landscapes 

Save Water, Escape Drought Injury,” California 

Agriculture, 45(6):19-21. 

Saratoga Horticultural Foundation, 1983, Success 

List of Water Conserving Plants, San Martin, 

CA. 

148

University of California Publications 

ANR# 

2975 Beutel, J., 1977, Saving Water in Home 

Orchards. 

21491 Snyder, R., Harivandi, A., Lanini, B., 1991, 

Turfgrass Evaporation Map Central Coast 

of California. 

UC Press 

3328 Generalized Plant Climate Map of California, 

1988. 

2149 Gibeault, V., Meyer, J., Harivandi, A., Henry, 

M., Cockerham, S., 1991, Managing 

Turfgrass During Drought. 

21333 Furuta, T., 1993, Protea Culture. 

21405 Gibeault, V., 1985, Turfgrass Water Conservation. 

2976 Harris, R., Coppock, R., 1976, Saving Water 

in Landscape Irrigation. 

4091 McClintock, E., and Leiser, A., 1979, An Annotated 

Checklist of Woody Ornamental 

Plants of California, Oregon and Washington. 

3276 McClintock, E., Mathias M., and Lewis, L., 

Ed., 1982, An Annotated Checklist of Ornamental 

Plants of Coastal Southern California. 

21432 Snyder, R., Harivandi, A., 1988, Lawn Watering 

Requirements Along California’s 

Central Coast. 

21426 Snyder, R., Pruitt, W., and Shaw, D., 1987, 

Determining Daily Reference Evapotranspiration 

(ETo). 

Hickman, James, Ed., 1993, The Jepson Manual, 

Higher Plants of California, University of California 

Press, Berkeley. 

Mathias, Mildred, Ed., 1982, Flowering Plants in 

the Landscape, University of California Press, 

Berkeley. 

Other Resources 

• California Department of Water Resources 

Office of Water Use Efficiency 

901 P Street 

P. O.Box 942836 


(916) 651-9676 

www.owue.water.ca.gov 

• California Irrigation Management Information 

System (CIMIS) 

California Department of Water Resources 

Office of Water Use Efficiency 

P. O. Box 942836 


(916) 651-7030 

www.cimis.water.ca.gov 

• California Department of Water Resources 

Information: (800) 272-8869 

149

• Species list on the Internet: 

www.dpla.water.ca.gov/urban/conservation/ 

landscape/wucols/wucols.html 

• Integrated Pest Management 

www.ipm.ucdavis.edu 

• University of California Cooperative Extension 


625 Miramontes Street, Suite 200 

Half Moon Bay, California 94019 

(650) 726-9059 

Copies of this Guide 

This Guide is a free publication. Additional copies 

may be obtained from: 

Department of Water Resources 

Bulletins and Reports 

P. O. Box 942836 


(916) 653-1097 

• UC Cooperative Extension—County Offices 

(check local phone directory) 

Additions 

Additions to the WUCOLS list can be made. Submit 

species names to: 

Irrigation Water Needs Project 

UCCE 

625 Miramontes, Suite 200 

Half Moon Bay, California 94019 

Submitted names will be sent out for evaluation by 

committee members and additions will be made 

periodically. 

150

Guide to Estimating Irrigation Water Needs of Landscape Plantings

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?