Corylopsis pauciflora, the buttercup winter hazel, is one of the most charming plants in the witch hazel family.  It features unique and colorful leaves, attractive and lightly fragrant flowers, fall color and is a good size for smaller gardens.  It is the smallest and most compact growing member of the genus.  The genus name means resembling (“opsis”) the leaf of a Corylus, or common hazel (though they are not related).  The specific epithet, pauciflora, means “paucity of flowers” but this is something of a misnomer.  While it has the fewest flowers per raceme (2-5) in the genus, it more than makes up for it which the sheer number of flower buds on each branch.  The nodding flowers, found all along each branch, produce an overall effect is very showy in bloom.  Flower color is a softer yellow than other members of the winter hazel genus, but the creamy yellow is prominent even on a cloudy day.  Corylopsis pauciflora can bloom as early as mid-March, with flowers persisting 3-4 weeks.  Flowers can be still be found coming into bloom until May.  In some years it can rebloom in September, which is what
I observed on the plants at CUH this past year.  The flowers force well, and buttercup winter hazel makes a good choice to cut in February and bring indoors for early color.

Leaves emerge after the flowers, starting off a bright bronze and fading to a light green color.  Each leaf is edged in red-violet.  They are quite ornamental, with prominent veins and attractively toothed edges.  Fall color is in the yellow range.

Corylopsis pauciflora is a dense, multistemmed shrub that requires little pruning.  Growth is moderate but not rampant.  In habit it has a rather graceful form when grown in the open.    As seen at the Center for Urban Horticulture, it is also very attractive and successful espaliered against a trellis.  Our oldest plant, 2413-40-A is less than 4’ tall after 70 years and is later blooming (at least this year) than others in the collection.  This is likely due to its shadier location.  Flower buds were just beginning to open while others in sunnier spots had been bloom
ing 10 days earlier.   It has surely been pruned a few times over the decades, but is no worse for wear.

Buttercup winter hazel does well in most garden soils, only disliking unammended heavy clay.  While not commonly seen in retail nurseries, it can be found at local plant sales from specialty nurseries or procured by mail order.   It received an Award of Garden Merit from the Royal Horticultural Society, and is consistently promoted as one of the best late winter shrubs.  It is also a Great Plant Pick.

Common name:  buttercup winter hazel (sometimes spelled as winter-hazel or winterhazel)

Family:  Hamamelidaceae

Location:  Buttercup winter hazel can be viewed at both UWBG locations:  the Center for Urban Horticulture (CUH) and the Arboretum.  At CUH there are four plants.  Three (4-05-A, B & C), are espaliered along the west wall of the Northwest Horticultural Society Hall.  One young plant (197-15-A) is open grown in the bed north of the Fragrance Garden.  At the Arboretum there are five plants.  The oldest (2413-40-A) in the old witch hazel family section in grid 6-4E, at the west side of the grove of another witch hazel family member:  Sycopsis sinensis (fig hazel).  Three plants (636-62-A) are in the Japanese Garden.  A young plant (197-15-B) is in the Woodland Garden in grid 31-3E.

Origin:  Corylopsis pauciflora is native to Japan and Taiwan.  It was introduced to western horticulture by the Veitch & Sons Nursery of England, from Japan.   Most plants in cultivation are thought to be from Japanese plants.

Height and spread:  Buttercup winter hazel will reach 4-6’ high and wide in time.  It performs well in part shade and in woodland settings.  However, in the Pacific Northwest it will tolerate full sun as long as it is protected from freezing winds and reflected heat.

Hardiness:  Cold hardy to USDA Zone 6