Culture
Best grown in humusy, organically rich, medium moisture, acidic to neutral, well-drained soils in full sun to part shade. Performs well in sandy loams. Appreciates consistent moisture during hot summers.
Noteworthy Characteristics
Cornus kousa, commonly called Kousa dogwood, is a small, deciduous flowering tree or multi-stemmed shrub that typically grows 15-30’ tall, with a vase-shaped habit in the early years but eventually maturing to a more rounded form. Bloom occurs in late spring. The showy parts of the Kousa dogwood “flower” (3-5” across) are the four narrowly pointed petal-like white bracts which surround the center cluster of insignificant, yellowish-green, true flowers. Flowers are followed by berry-like fruits (to 1” diameter) which mature to a pinkish red in summer and persist into fall. Fruits are technically edible, but are usually left for the birds. Oval, pointed leaves (to 4” long) are dark green. Mottled, exfoliating, tan and gray bark on mature trees is attractive in winter.
Var. chinensis is native to China and is commonly called Chinese dogwood. It is a small, deciduous, flowering tree or multi-stemmed shrub that typically grows 15-30’ tall with a vase-shaped habit in the early years, eventually maturing to a more rounded form. Var. chinensis is very similar to the species except for having slightly larger flower bracts, larger fruit, and larger, smoother and often more pubescent leaves. It is particularly noted for (a) abundant white-bracted flowers which bloom in profusion in May, (b) edible red berries (to 1.25" diameter) which mature in summer, and (c) showy orange-red fall foliage color.
Genus name comes from the Latin word cornus meaning "horn", possibly in reference to the strength and density of the wood. Cornus is also the Latin name for cornelian cherry (Cornus mas). May also be related to the Greek kerasos meaning "cherry".
Specific epithet is the Japanese name for this species.
‘Milky Way’ is one of the most popular cultivars sold in commerce today. It is a broad, bushy tree that is particularly noted for its abundant flowers and showy fruit. It typically matures to 20’ tall and as wide. Flower bracts are creamy white and bloom in profusion in June. Red berries mature in summer. Berries are exceptionally large and are edible (inner custard-like consistency) off the plant. Birds also love the fruit. Fruits persist on the plants into fall past the point of foliage drop. Oval, pointed, dark green leaves (to 4” long) turn orange-red to scarlet in autumn. Mottled, exfoliating, tan and gray bark is attractive in winter. Cultivar name suggests that the profuse bloom of flowers each year is suggestive of the billions of stars in the Milky Way.
Problems
No serious insect or disease problems. Kousa dogwoods generally have better disease resistance than flowering dogwoods (Cornus florida). Excellent resistance to anthracnose. Stressed trees may become vulnerable to borers. In full sun locations, leaf scorch may appear, particularly if plants are sited in full sun in hot, windy or droughty conditions.
Uses
A stunning small flowering tree or large shrub with excellent flowers, showy fruit, interesing summer foliage color, good fall color and some winter interest. Plant as a specimen or in small groupings on residential property around homes, near patios or in lawns. Also effective in shrub borders, woodland gardens or bird gardens.