Kousa Dogwood
Cornus kousa
The Kousa Dogwood (Cornus kousa) is a small deciduous tree or large shrub in the family Cornaceae, prized both for its spectacular ornamental display and its edible fruit. Native to East Asia, it is widely cultivated in temperate regions around the world as a landscape specimen.
Unlike its North American cousin Cornus florida, the Kousa Dogwood blooms later in spring and is notably more resistant to anthracnose disease (Discula destructiva), making it a preferred choice in many urban and suburban plantings.
• Typically grows 5–10 m tall with a spreading, multi-stemmed habit
• Known for its four-petaled white to pinkish bracts that appear to "bloom" in late spring
• Produces distinctive raspberry-like aggregate fruits in late summer to autumn
• Widely regarded as one of the most ornamental of all dogwood species
• First described scientifically by the German botanist Philipp Franz von Siebold in the 19th century
• Introduced to Western horticulture in 1875
• The specific epithet "kousa" derives from the Japanese word "kōsu" (コウサ), referring to the tree
• Has since become naturalized in parts of the northeastern United States
• Numerous cultivars have been developed, including 'Milky Way,' 'Satomi,' 'Beni Fuji,' and 'Wolf Eyes,' selected for bract color, variegated foliage, or compact growth habit
Bark & Branches:
• Bark is smooth and gray when young, developing an attractive mottled, exfoliating pattern with age — revealing patches of tan, gray, and brown
• Branches grow in a characteristic horizontal, tiered arrangement
Leaves:
• Simple, opposite, ovate to elliptic (4–10 cm long)
• Dark green and glossy in summer, turning shades of red to purple in autumn
• Entire margins with prominent, curved venation
Flowers:
• True flowers are small, yellowish-green, and clustered in dense heads (~2 cm across)
• Surrounded by four large, showy, petal-like bracts (3–7 cm long) that are white, aging to pink
• Bracts are pointed at the tip — a key distinguishing feature from Cornus florida, which has rounded, notched bracts
• Blooms in late May to June, typically 3–4 weeks after Cornus florida
Fruit:
• A globose, compound aggregate fruit (syncarp), 2–3.5 cm in diameter
• Resembles a raspberry in appearance; pink to bright red when ripe
• Surface covered with small, knobby protuberances
• Flesh is soft, creamy, and sweet when fully ripe, with a flavor often compared to a ripe persimmon or mild banana
• Contains numerous small, hard seeds embedded in the pulp
• Fruits hang singly on long stalks from branch tips
• Prefers partial shade when young but tolerates full sun once established
• Thrives in well-drained, slightly acidic soils (pH 5.5–6.5)
• Moderately drought-tolerant once established, though performs best with consistent moisture
• Flowers are pollinated primarily by bees and other generalist insect pollinators
• Fruits are consumed by birds and small mammals, which aid in seed dispersal
• Notable resistance to dogwood anthracnose (Discula destructiva), a devastating fungal disease that has severely impacted native Cornus florida populations in North America
• Also shows good resistance to powdery mildew compared to other dogwood species
Light:
• Performs best in full sun to partial shade
• In hotter climates (USDA zones 7–8), afternoon shade helps prevent leaf scorch
Soil:
• Prefers moist, well-drained, slightly acidic soil rich in organic matter
• Tolerates clay soils if drainage is adequate
• Mulch around the root zone to retain moisture and regulate soil temperature
Watering:
• Water regularly during the first two growing seasons to establish a strong root system
• Once established, moderately drought-tolerant but benefits from supplemental watering during prolonged dry spells
Temperature:
• Hardy in USDA zones 5–8
• Tolerates winter cold down to approximately -29°C (-20°F)
• Late spring frosts can occasionally damage emerging flower bracts
Pruning:
• Minimal pruning required; best done in late winter or early spring before new growth begins
• Remove dead, damaged, or crossing branches to maintain the tree's natural form
• Avoid heavy pruning, as the tree heals slowly
Propagation:
• By seed (requires cold stratification for 90–120 days at 4°C)
• By semi-hardwood cuttings taken in mid to late summer
• By grafting onto Cornus kousa or Cornus florida rootstock
Common Problems:
• Generally pest- and disease-free
• Occasional issues with dogwood borer (Synanthedon scitula) in stressed trees
• Leaf scorch in excessively hot, dry, or windy conditions
• Fruit drop can create minor litter beneath the tree
Fun Fact
The Kousa Dogwood's fruit is not only ornamental but genuinely edible and has a growing following among foragers and food enthusiasts: • The ripe fruit's creamy flesh is sweet and often described as tasting like a blend of persimmon, mango, and apricot • Commonly used to make jams, jellies, syrups, sauces, and even wine in its native range • In Korea, the fruit (known as "sansuyu") is used in traditional preparations and is believed to have medicinal properties • The fruit is rich in calcium and potassium A remarkable botanical distinction: • What most people think of as the "petals" of the Kousa Dogwood are actually bracts — modified leaves that surround the true flowers • The real flowers are the tiny, inconspicuous yellowish-green cluster at the center of the four showy bracts • This is the same strategy used by poinsettias, bougainvillea, and other plants where colorful bracts do the work of attracting pollinators The Kousa Dogwood has become a symbol of resilience in American horticulture: • After dogwood anthracnose devastated millions of native Cornus florida trees in eastern North American forests beginning in the 1970s, the disease-resistant Cornus kousa was widely planted as a replacement • It has since become one of the most popular ornamental trees in the United States, with hundreds of thousands sold annually by nurseries
Learn moreComments (0)
No comments yet. Be the first to share your thoughts!
