Kousa Dogwood: an Early Summer Delight

Kousa Dogwood
Kousa Dogwood

Kousa dogwood is a small tree with white leaves that resemble the most spectacular of flowers. Photo: Aleksandra Monk.

In the Seattle Japanese Garden, this beautiful small tree, Cornus kousa var. chinensis, is located  near the path on the pond’s east side.

It’s a form of the more well-known Kousa Dogwood (Cornus kousa, also known as Korean Dogwood), which is native to low mountains of Korea, Japan and China.  In Japan, it was called yamaboshi, and used to make implements.

Variety chinensis, found in our Japanese Garden, is known as Chinese Dogwood.  Both forms are small deciduous trees treasured for their beauty and flowering period -- early summer when most other flowering trees have finished blooming.  They are also much more disease-resistant than Cornus florida, native to the Eastern United States but widely planted for many decades in the Pacific Northwest and elsewhere.

Although its true flowers are small, round and inconspicuous, the Kousa Dogwood displays four spectacular white pointed bracts (modified leaves that look like flowers) over a long period in late May and June.  The red fruits develop in late summer or early fall, resemble raspberries, and are edible but mealy.

Leaves are dark green and egg-shaped, with a pointed leaf tip, turning shades of maroon or scarlet in fall.

Young trees are vase-shaped, becoming more rounded with age.  The mature size (about 25 years) is 20-30 feet tall and wide.  With its bark in patterns of gray, tan and brown, and its horizontal branching pattern at maturity, this is a 4-season tree -- beautiful in winter as well as throughout the growing season.

Chinese Dogwood (Cornus kousa var. chinensis) was introduced from China in 1907 by the English plant hunter, E. H. Wilson.  It’s noted for larger bracts and for growing more freely than the straight species, C. kousa.  It may also be somewhat narrower in habit, even when mature.  However, according to Bean and other woody plant authorities, there isn’t much botanical difference between this form and the species tree.  Nevertheless, the specimen in the Japanese Garden is a spectacular tree, in and out of flower.

Corinne Kennedy is a trained guide for Seattle Japanese Garden and a contributor to the garden's blog.