Culture
Easily grown in average, medium moisture, well-drained soil in full sun to part shade. Prefers moist loams, but tolerates a wide range of soils. Best with consistent and even moisture. Prune as needed immediately after flowering.
Noteworthy Characteristics
Viburnum plicatum is a dense, upright, multi-stemmed, deciduous shrub that typically matures to 8-15’ tall with a slightly larger spread. Ovate, toothed, strongly-veined, dark green leaves (to 4” long) have pleated upper surfaces. Leaves turn burgundy red to purplish red in fall. Two different forms of this shrub are commonly sold in commerce: (1) Japanese snowball bush (f. plicatum) which is the type form featuring sterile, snowball-like, orbicular inflorescences (2-3” diameter cymes) of non-fragrant, showy white flowers along the branches in spring with no subsequent fruit and (2) doublefile viburnum (f. tomentosum) which is the wild-related taxon featuring fertile, flat-topped flower clusters (2-4” diameter cymes) which bloom along tiered horizontal branches in doublefile form, each cluster containing an outer ring of large showy sterile florets surrounding a center mass of tiny non-showy fertile florets which when fertilized give way to egg-shaped fruits and viable seed. Bloom time of f. plicatum typically occurs about two weeks later than that of f. tomentosum. Mature height of f. plicatum may rise to as much as 15’ tall, but mature height of f. tomentosum typically will not exceed 10’ tall. Except as to flower structure, bloom time, height and branching habit, both forms are otherwise very similar and commonly sold in commerce under a number of different cultivar names.
The sterile snowball form (f. plicatum) is known from cultivation only (first observed as a garden plant in Japan). It was discovered prior in time to the discovery of the wild fertile doublefile form (f. tomentosum) from which it was actually developed. As a result of this inverted schedule of discovery, the sterile form was mistakenly given a species name (Viburnum plicatum) and the subsequently discovered fertile form (f. tomentosum) was named as if it were a variety of the species. The wild form (f. tomentosum) is native to forests and thickets in China and Japan.
Forma tomentosum has fine hairs on young stems and leaf undersides.
Genus name comes from the Latin name of a species plant.
Specific epithet means pleated or folded in reference to leaf veins.
'Shasta' is a cultivar that typically matures to 6-8’ (sometimes to 10’) tall and spreads to 9-12’ wide. This is a large shrub that produces abundant flowers in spring on horizontal branches followed by abundant red maturing to black fruits. Large flower clusters (each to 6” wide) feature showy outer snow-white sterile flowers (each to 2” wide). Introduced in 1979 by the U.S. National Arboretum.
Problems
No serious insect or disease problems. Squirrels have been known to eat unopened flower buds in late winter which can result in reduced blooming or a lack of blooms altogether.
Uses
Specimen or groups. Shrub borders, foundations or hedges.