Cornus kousa (var. chinensis) Japanese dogwood

Japanese dogwood is a showy, beautifully structured deciduous shrub native to Asia. It most often flowers in June and, like many plant species, it is something of a trickster, because the attractive parts visible at first glance are not the true flowers themselves but the coloured bracts surrounding the actual inflorescence. The true flowers are small, yellow-green and inconspicuous, arranged in a compact, spherical head. This is encircled by four prominent bracts that are narrowly ovate to lanceolate, distinctly pointed, initially slightly greenish and later creamy white, with the entire inflorescence reaching a diameter of approximately 7 to 13 cm. Because flowering takes place in the height of the season against a backdrop of fully developed foliage, the colour contrast is striking and, on older, heavily flowering plants, often breathtaking.

The leaves are deciduous, elliptic to ovate with a pointed tip, usually 4 to 10 cm long, with slightly undulate margins and often gently drooping, reminiscent of pear leaves. In autumn they turn vivid shades of fiery orange, red and deep wine tones. Before that, however, the fruits ripen, most commonly from late August into early September. These are 2 to 3 cm wide, spherical fruits resembling lychee, with a raspberry-pink skin and orange flesh. They are edible and, in some clones, quite palatable, but they contain large seeds, so the amount of flesh is limited and the skin may be slightly bitter.

Japanese dogwood forms a spreading shrub or small tree with a characteristic wide V-shaped structure, botanically described as a funnel-shaped habit. It is often multi-stemmed and only rarely trained as a single-stem tree. Growth is moderate and follows a distinctive pattern: the plant first produces longer shoots, which in subsequent years are filled in with short lateral branches, creating flat, richly layered tiers that give rise to the characteristic tiered crown effect. Under local conditions it typically reaches 3 to 5 metres in height, while in its native range and under ideal growing conditions in open landscapes it can attain significantly larger dimensions. Older trunks develop an attractive, mottled, exfoliating bark in shades of grey to light brown.

In the past, Japanese dogwood was separated in parts of its range, especially in China, as var. chinensis and for a long time was also listed in nurseries as a distinct entity based on its more vigorous growth, larger bracts and looser inflorescence structure. These traits, however, vary continuously across the natural range of the species and do not represent stable diagnostic differences. Modern nomenclature no longer distinguishes them and includes all such forms within the broadly defined species Cornus kousa. The name var. chinensis therefore survives today mainly in horticultural practice as a historical or commercial term for strongly growing populations of Chinese origin, rather than as a valid botanical unit.

Japanese dogwoods prefer acidic to very acidic, fertile and light soils that do not dry out over long periods. Planting in partial shade, where they are sometimes said to be protected from summer drought, has proven unsatisfactory, as plants there usually flower less and develop sparser crowns. Much better results are achieved in full sun, combined with a good mulch layer that helps retain soil moisture and protects the root system. During prolonged dry periods, supplemental watering is advisable, especially for younger plants. In sunny positions, dogwoods flower more abundantly and grow denser and healthier. If fertilised, products that support flower formation and healthy leaf growth are recommended, rather than fertilisers aimed at rapid vegetative growth. Pruning is generally undesirable and should only be carried out after flowering to rejuvenate older plants. Japanese dogwood is fully hardy to approximately −29 °C.

Last update 16-01-2009; 11-02-2026