Easily grown in average, medium, well-drained soils in full sun to part shade. Best flowering in full sun. Prefers moist, acidic, organically rich soils. Promptly remove root suckers to prevent colonial spread. Prune in spring after flowering to control shape and size.
Hamamelis x intermedia hybrids are crosses between Japanese witch hazel (H. japonica) and Chinese witch hazel (H. mollis). They are somewhat coarse, loosely-branched, medium to large, deciduous shrubs that typically grow 12-20’ tall. They are particularly noted for their spidery, often fragrant, mid- to late winter flowers which appear before the spring foliage emerges.
Genus name comes from the Greek words hama meaning at the same time and melon meaning apple or fruit in reference to the occurrence of both fruit and flowers at the same time on this shrub (particularly in the case of fall flowering members of the genus).
‘Arnold Promise’ is an upright, vase-shaped cultivar with ascending branches and a spreading habit. It will typically grow 12-15’ tall and is noted for its sweetly fragrant flowers and later bloom than most of the other x intemedia cultivars. Axillary clusters of bright yellow flowers (to 1” long), each with four narrow, ribbon-like, crinkled petals and a reddish-green calyx cup, bloom along the stems in February to March. Broad-oval, green leaves (to 6” long). Yellow-orange to yellow fall color can be quite attractive. An introduction of the Arnold Arboretum in Boston. A Royal Horticutural Society of Great Britain Award of Garden Merit plant (1993).
No serious insect or disease problems. Occasional insect galls (small wasps) appear on the foliage. Japanese beetles may chew on the leaves in some areas.
Shrub borders, woodland gardens. Screen or tall hedge. Good specimen due to late winter flowers, attractive summer foliage and fall color.