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.
'Ilvobo', commonly sold under the trade name of BOBO, is a compact cultivar that typically grows in an upright rounded mound to only 2-3' tall and to 3-4' wide. It is the product of an open pollination in a controlled breeding program that took place in Melle, Belgium in 2003 between Hydrangea paniculata 'Pink Diamond' (female parent) and an unknown Hydrangea paniculata (male parent). 'Ilvobo' is particularly noted for its dwarf/compact mounded shape, free branching habit, early flowering, strong stems, and conical flowering habit. Abundant sterile white flowers bloom early and profusely in large flower panicles (each to 11" long). Strong stiff stems hold the panicles upright with no drooping. Flowers gradually acquire pink to light purple tones as they mature. Flowers typically bloom from July through September. Ovate, serrate, dark green leaves (to 2 1/2” long) produce generally undistinguished fall color. Flower panicles may be cut for fresh arrangements or for drying, or may be left on the plant where they often persist into winter. U. S. Plant Patent PP22,782 was issued on May 25, 2010.
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.