Culture
Best grown in organically rich, medium moisture, well-drained soils in full sun to part shade. Can be trained as a small single trunk tree, but is best grown as a large, multi-stemmed shrub. May display best shrub form if regularly pruned to a height of 6-10’ tall. This is one of the most winter hardy of the hydrangeas. It thrives in urban conditions. Bloom occurs on current season’s growth, so prune as needed in late winter to early spring.
Larger flower panicles can be obtained by thinning the plants to 5-10 primary shoots. In full bloom, the weight of the flower panicles will typically cause the branches to arch downward.
Noteworthy Characteristics
Hydrangea paniculata, commonly called panicle hydrangea, is a vigorous, upright, rapid-growing, somewhat coarsely textured, deciduous shrub that is native to China and Japan. It typically grows to 8-15’ (less frequently to 25’) tall, and features oval to ovate dark green leaves and upright, sharply-pointed, conical, terminal flower panicles (to 6-8” long) containing both fertile and sterile flowers (mostly non-showy fertile flowers) that bloom from mid-summer into fall.
The genus name Hydrangea comes from hydor meaning "water" and aggeion meaning "vessel", in reference to the cup-like capsular fruit.
The specific epithet paniculata refers to the arrangement of the flowers in panicles.
‘White Moth’ typically grows in an upright rounded form to 7’ tall with a spread to 8’ wide. It is particularly noted for its mid-summer into fall bloom of flowers in irregular, somewhat orbicular panicles (each to 14” wide). Bloom is on new wood and continues throughout summer into fall. Each panicle contains abundant, showy, creamy white, sterile florets which remain white throughout the bloom season. White florets cover many of the tiny non-showy green fertile florets.
Problems
Some susceptibility to bud blight, bacterial wilt, leaf spot, rust and mildew. Aphids and mites are occasional visitors.
Uses
Mass or group in a mixed shrub border or open woodland garden. Also effective as a lawn specimen, accent or hedge. Provides late summer bloom when few other shrubs are in flower.