Tree Profiles: Kousa Dogwood, Part 2 (Cornus kousa)
This the second of a two part series on Kousa dogwood. The following describes propagation methods for Kousa dogwood, the tree’s root system, preferred soil types, cultivars, damaging agents and pests, allegenic potential, and uses.
Kousa dogwood (Cornus kousa), also referred to as Benthamia kousa, Cynoxylon kousa, Chinese dogwood, Kousa, Korean dogwood, and Japanese dogwood is a small, deciduous tree or multi-stemmed shrub in the family Cornacea. Kousa dogwood was first observed in the United States in 1875. It has since become a popular ornamental plant. It is renown for the profusion of star-like blooms it produces in spring, and for its dense, branching canopy when mature. It also displays lush purple to red fall foliage. Kousa dogwood is resistant to many insects and diseases that afflict other dogwoods.
Kousa dogwood is typically cultivated through seed. Cultivation from cuttings can also be achieved, but the procedure is more arduous to perform, and less efficient.
Kousa dogwood has a shallow root system. It can grow well in acidic, clay, loamy, moist, and well-drained soils. The plant’s root system is vulnerable to root rot, particularly when planted in clay soil. Kousa dogwood exhibits some drought resistance, but is most partial to average moisture. To grow and expand, the plant’s roots require full sun to partial shade. Proper mulching is essential to Kousa dogwood’s root system. Applying a layer of organic mulch around the base of Kousa dogwoods will insulate the roots, while improving the soil quality.
Soil and Topography
Kousa dogwood flourishes when it is planted in acidic soil. It can also grow in neutral soils, but may develop at a slower rate. In high pH soils, Kousa dogwood may exhibit symptoms of chlorosis.
Numerous varieties have been cultivated from Kousa dogwood. Some of the most frequently selected culivars include ‘Beni Fuji’, ‘Champion’s Gold’, ‘Elizabeth Lustgarten’, ‘Gold Star’, ‘Heart Throb’, ‘John Slocock’, ‘Lustgarten Weeping’, ‘Little Beauty’, ‘Milky Way’, ‘Satomi’ (sometimes called ‘Rosabella’), ‘Snowboy’, ‘Summer Fun’, ‘Summer Gold’, ‘Summer Stars’, ‘Temple Jewel’, ‘Variegata’, ‘var. chinensis’, ‘Wisley Queen’, and ‘Wolf Eyes’.
Damaging Agents and Pests
Kousa dogwood is resistant to most pests and disease pathogens, including dogwood anthracnose, which can cripple flowering dogwood. It is vulnerable to infestation from aphids and borers, and may be plagued by leaf spot diseases, crown canker disease, leaf scorch, and root rot.
Kousa dogwood is a mild allergen. As such, it is an ideal plant for those that are vulnerable to pollen.
- Due to its relatively compact size and brilliant floral dispay, Kousa dogwood is often planted in landscape settings. Kousa dogwood can be grown as a container plant. Small groups of Kousa dogwood can be planted together, though sufficient spacing is required. Individual dogwoods can be planted near utility lines, buildings, and walls. Kousa dogwood is often selected as an alternative to flowering dogwood, due to its disease resistance.
- Kousa dogwood has edible fruit, which is sometimes used to craft wine. The rind of the fruit may also be consumed, but has a bitter taste. The fruit are used as a food source for songbirds and squirrels. The seeds can be ground into a paste, and used as ingredients in a bevy of jams and sauces.
- When young, Kousa dogwood leaves are edible, and may be feasted on, or brewed in a tea.
- Kousa dogwood’s vibrant flowers attract beneficial insects, such as bees and butterflies.