Cornus kousa

Kousa dogwood (Cornus kousa)
Scientific name	Cornus kousa
Common names	Kousa dogwood; Korean dogwood; Japanese dogwood
Genus	Cornus
Family	Cornaceae
Order	Cornales
Native range	Sikkim (East Himalaya), China, Japan, Korea, Taiwan; introduced in Hawaii, Massachusetts, New York, and North Carolina
Habit	Deciduous shrub or small tree; upright and vase-shaped when young, rounded and wide-spreading at maturity
Mature size	About 8–10 m (25–30 ft) tall, slow-growing
Fruit	Pinkish-red compound syncarp of fused drupelets about 2 cm across; sweet custard-like pulp, tough skin, stony seeds
Propagation	Cleaned fresh seed, cold-stratified stored seed, half-ripe or mature-wood cuttings, layering; named cultivars chip-budded or grafted
Years to fruit	About 5 years from a young planting to first bloom (grower-reported)
Cold tolerance	Hardy to about −20 °C; USDA zones 5–8
Climate	Cool-temperate East Asia; moist, well-drained sites

Cornus kousa, the kousa dogwood, also called Korean dogwood or Japanese dogwood, is a small deciduous tree native to temperate East Asia, from Sikkim through China, Japan, Korea, and Taiwan.^[1] It is placed in the dogwood genus Cornus of the family Cornaceae and is accepted in the taxonomic backbones.^[2] In the garden it is valued for its late-spring bracts, long fall color, and an edible compound fruit that has a following among temperate fruit growers. The showy white parts are bracts, and in the northern hemisphere the tree blooms about a month later than the flowering dogwood, after the leaves have expanded.^[3]

Description

Kousa dogwood is a slow-growing, small- to medium-sized deciduous tree reaching about 8–10 m (25–30 ft) at maturity. Young trees are upright and vase-shaped; mature trees become rounded and wide-spreading.^[3]

The showy white parts in late spring are bracts surrounding small heads of true flowers; some nursery forms carry pink bracts. Bloom occurs about a month later than the flowering dogwood, with the flowers nestled among fresh green leaves, and fall color is reddish-purple to scarlet, holding three to five weeks.^[3]

The fruit is a pinkish-red compound syncarp of fused drupelets about 2 cm across. The skin is tough and somewhat bitter, the pulp sweet with a custard-like texture, and the seeds hard and stony.^[4]

Two subspecies are accepted: Cornus kousa subsp. kousa (Japan and Korea) and Cornus kousa subsp. chinensis (China). A 2024 RADseq study of 313 big-bracted dogwood accessions found Chinese-collected plants genetically distinct from Japanese and Korean accessions, and found many pink-bracted cultivars sold under different names to be genetically identical.^[5]

Cultivation

Kousa dogwood in flower, London, Ontario

Compared with the flowering dogwood, kousa dogwood is more drought-tolerant, more cold-hardy, and more disease-resistant, with less susceptibility to dogwood anthracnose. Research and extension context attribute its rise in popularity in the United States to resistance to powdery mildew, dogwood anthracnose, and dogwood borer, which are common problems on Cornus florida.^[3][5]

Soil and water

Extension guidance calls for a well-drained, acidic soil; the tree tolerates some dry soil once established but will not survive waterlogged ground.^[3] Aggregator guidance lists soil from mildly acid to neutral or basic, notes a dislike of shallow chalky soils, and recommends a moist, rich, well-drained loam.^[4] The grower-care list for the Big Apple selection adds the genus pattern: dogwoods like acidic soil rich in organic material, always moist but well-drained, with mulched roots and extra watering in dry spells.^[6]

Sun and humidity

Kousa dogwood prefers a sunny position and tolerates moderate shade; light afternoon shade is useful where summers are hot.^[3] It is content with at least a partially sunny position in ordinary garden conditions.^[4]

Seasonal changes

In the native cool-temperate cycle, flowers open in June, seeds ripen September to October, and leaves turn color before falling in autumn.^[4] In cultivation the bloom runs about a month later than flowering dogwood, and fall color holds three to five weeks.^[3] The species is rated hardy in USDA zones 5–8, to about −20 °C.^[4]

Propagation

Kousa dogwood fruits, Shiga Prefecture, Japan

Fresh seed should be cleaned of the fruit flesh before sowing, since the pulp contains germination inhibitors; stored seed benefits from three to four months of cold stratification, with scarification sometimes helpful. Germination, especially of stored seed, can be very slow, taking 18 months or more.^[4]

Half-ripe side-shoot cuttings can be taken in July or August, mature-wood heel cuttings in autumn, and layering of new growth in June or July roots within about nine months.^[4] Named cultivars are propagated asexually, normally through chip budding, so vegetatively produced plants come true.^[5]

Flowering, fruiting, and harvest

Flowers are hermaphrodite and insect-pollinated, opening in June, and the seeds ripen September to October.^[4] Seedling-grown trees take time to start: one grower planted a young tree in spring 2020 and counted its first blossoms in 2025, about five years after planting.^[7]

Fruit is worth eating only when dead-ripe, very soft, dropping from the tree when ready. Underripe fruit is sandy and bland. Ripe fruit does not keep: it quickly starts to taste fermented, so check the tree daily and eat or process promptly at full ripeness.^[7][8] Each fruit is roughly the size of a ping-pong ball, red, with one to three pits; the common eating method is to split or squeeze the fruit, suck out the pulp, and discard skin and pits.^[8]

Fruit and uses

Kousa dogwood fruit boiled to make jelly

The fruit is edible raw or cooked.^[4] In Korea and China it has traditional therapeutic use, and among Cornus species kousa carries some of the largest fruits, with a sweet flavor and occasional use in wine production.^[9]

First-hand taste reports range widely from tree to tree. Growers describe good ripe fruit as buttered-peach, peachy, persimmon-like, tropical, or custardy, and poor or unripe fruit as gritty, sandy, seedy, or mild; sweetness, texture, pulp color, and seediness all vary between individuals.^[8][10] Growers note that birds often take the best-tasting fruit first, so daily checks and harvest at full ripeness protect the crop.^[10] Reddit reports describe the pulp as like a sandy peach or custardy and closer to pawpaw, usually with two or more pits, with the peel texture avoided by squeezing out the pulp.^[11] The fruit can also be boiled to make jelly^[11], and dropped fruit left on the ground ferments and can attract wasps, so keep the drop area picked up.^[3]

Cultivars and selections

Big Apple is the best-documented fruit selection. It was found and selected by Polly Hill in the United States in the 1960s, from seeds obtained from M.M. Brubaker of Pennsylvania. Its snow-white bracts turn pink as they wither, and the bright pink edible fruits have a rough bitter skin and sweet flesh with few seeds. The listing claims fruit up to 4 cm across, but notes its own young plants have so far produced fruit just over 2 cm, so the large figure is a nursery claim rather than a measured species norm.^[6] Big Apple is rated for USDA zone 5, down to about −29 °C, grows to 3–5 m tall by 2–3 m wide, and blooms June to July. The retail listing confirms hardiness to about −23.5 °C, full sun or partial shade, moist non-limestone soil, roughly 5 m height and spread, and fiery orange autumn color.^[12]

Named fruit selections circulate mainly from Ukraine and the Czech Republic. Julian has bracts curved up at the tip, excellent fall color, and fruit larger than 1 inch across; National is a vigorous vase-shaped tree with exfoliating bark, large creamy white bracts, and larger-than-normal fruit; Teutonia is described with 3–4 cm fruit whose flavor sits between strawberries and mangoes, closest to a kaki persimmon. These attributes come from the nursery listing and forum reports, not from a controlled comparison. Mandarin Jewel and Cornus kousa var. chinensis selections are reported with yellow or orange fruit, and hybrids with other big-bracted dogwoods include 'Porlock', 'Gloria Birkett', 'Starlight', 'Venus', 'Hyperion', and 'Saturn'.^[13] Ornamental cultivars are far more numerous; the NCSU extension list includes Satomi (pink), Wolf Eyes, Milky Way (flowering may appear biennial), Moonbeam, Scarlet Fire, Gold Star, Gold Cup, Greensleeves, Samaritan, and Summer Fun.^[3] Because the 2024 genetics work found identical pink-bracted cultivars sold under different names, treat cultivar labels with caution and prefer a named fruit selection when fruit size is the goal.^[5]

Photos

References

• ↑ [1] Kew Plants of the World Online: Cornus kousa.

• ↑ [2] GBIF Backbone Taxonomy: Cornus kousa.

• ↑ [3] Cornus kousa | North Carolina Extension Gardener Plant Toolbox.

• ↑ [4] Kousa Dogwood, Japanese Dogwood | Plants For A Future.

• ↑ [5] Genetic relationships among 313 big-bracted dogwood accessions | PLOS ONE.

• ↑ [6] Cornus kousa Big Apple Japanese dogwood | Havlis.cz.

• ↑ [7] Kousa Dogwood Berries | Growing Fruit forum.

• ↑ [8] In Praise of Cornus Kousa | Growing Fruit forum.

• ↑ [9] Cornus kousa fruits: traditional use and phytochemistry | PMC.

• ↑ [10] Dogwood Fruit | Growing Fruit forum.

• ↑ [11] I've never seen this berry | Reddit r/Berries.

• ↑ [12] Cornus kousa Big Apple | Promesse de Fleurs.

• ↑ [13] Cornus Kousa varieties | Growing Fruit forum.

Image credits

• Cornus kousa in Itschnach 1.jpg: whole-plant habit photograph by Armineaghayan, Wikimedia Commons; CC BY-SA 4.0. File page: Cornus kousa in Itschnach 1.jpg.
• Cornus kousa flowers.jpg: flowering-bract photograph by Gogerr, Wikimedia Commons; CC BY-SA 4.0. File page: Cornus kousa flowers.jpg.
• Cornus kousa (fruits).jpg: ripe-fruit photograph by Alpsdake, Wikimedia Commons; CC BY-SA 4.0. File page: Cornus kousa (fruits).jpg.
• Boiling Cornus kousa fruit.jpg: culinary-processing photograph by Mbenigno22, Wikimedia Commons; CC0 public-domain dedication. File page: Boiling Cornus kousa fruit.jpg.
• B15 Cornus kousa (Kousa Dogwood) Close-up.jpg: close-up of ripe fruit by Slarson789 (own work), Wikimedia Commons; CC BY-SA 3.0. File page: B15 Cornus kousa (Kousa Dogwood) Close-up.jpg.