Tree · Cornaceae
Kousa Dogwood
Cornus kousa
A small, forgiving tree that gives you star-shaped blooms, edible fruit, and peeling bark through all four seasons.
Full sun
Every 5–10 days
USDA 5–8
15–30 ft · 4.6–9.1 m
Overview
Kousa dogwood is a wonderfully rewarding tree for a first garden, and it earns its keep by shifting with every season. Late spring brings a big flush of pointed, star-shaped bracts, and unlike the native flowering dogwood it opens after the leaves are out, so the blooms rest against a soft green backdrop. Come late summer it hangs with pinkish-red fruit that birds adore and you can eat too.
It stays a comfortable size, reaching 15 to 30 feet (4.6 to 9.1 m) tall and about as wide, wearing a vase shape when young that rounds out as it ages. Because the growth is slow, it will never crowd out a small yard, and you have plenty of time to watch it settle in. As the trunk matures it peels away patches of bark to reveal a mottled, camouflage pattern that keeps the tree lovely right through winter.
Many gardeners choose it as an easier, sturdier stand-in for Cornus florida, and for good reason. It resists the anthracnose and borers that trouble the native dogwood, asks very little once it has settled, and takes cold down to -20°F (-29°C) without complaint. Give it decent soil and steady moisture and it will largely look after itself, mistakes and all.
Care
The short version: give it full sun to part shade in rich, slightly acidic, well-drained soil, and keep it evenly moist through the heat of summer. Mulch the roots, prune almost never, and let this slow grower find its feet at its own gentle pace.
Light
Kousa dogwood is happiest in full sun to part shade, so you have room to play. Full sun brings the heaviest bloom, though in hot regions a little afternoon shade spares the leaves from scorching in midsummer.
Water
Aim to keep the soil at a steady, medium moisture, watering every 5 to 10 days and a bit more often through a hot, dry spell to head off leaf scorch. Once it's established it copes with drought better than the native dogwood, though it never enjoys sitting in waterlogged ground.
Soil
Plant it in rich, humusy, well-drained loam on the acidic to neutral side, ideally a pH of 5.5 to 7.0. Mixing in some compost and topping with an acidic organic mulch keeps the roots cool and well fed, which the tree quietly appreciates.
Temperature
This is a hardy tree that handles a wide range, from -20°F to 95°F (-29°C to 35°C), covering USDA zones 5 through 8. It takes hard winters in stride and only really struggles where summers turn relentlessly hot and dry.
Humidity
Ordinary outdoor humidity suits it just fine, so there's no figure to fuss over. What helps more is good air movement, since crowded, stagnant growth is what tempts powdery mildew onto the leaves.
Feeding
A single feeding in early spring with a balanced slow-release fertilizer is plenty, or you can simply top-dress with acidic compost or mulch. This slow grower has modest needs and would rather not be pushed.
Pruning
You can relax here, because pruning is best kept to a minimum. Take out only dead, damaged, or crossing branches, and do it just after flowering in late spring to early summer so you don't accidentally snip off next year's buds.
Repotting
A kousa dogwood is rarely kept in a container for long, so repotting hardly ever comes up. If yours is potted and the roots begin circling or pushing through the drainage holes, move it to a bigger container or, better still, into the ground.
Size & spacing
Look forward to a mature tree of 15 to 30 feet (4.6 to 9.1 m) tall with a spread to match. Give it that much open room so the broad, rounded crown can fill out and air can drift through the branches.
When to plant
Kousa dogwood is a woody tree you plant once and keep for decades, so there's no rush and little to get wrong. Set it out in spring or fall so the roots can settle before the next round of heat or hard frost, and look forward to the bloom in late spring with edible fruit ripening from late summer into early fall.
Northern hemisphere
Southern hemisphere
Typical months for a temperate climate: start earlier in warm zones, later where spring frosts linger.
- Plant: spring or fall
- Harvest: Blooms late spring to early summer (May to June), after leaves emerge; pinkish-red edible fruit ripens late summer to early fall.
Hardiness
USDA hardiness zones: 5–8
Temperature: down to -29°C
Troubleshooting
Almost all kousa dogwood trouble shows up on the leaves, and more often than not the site or the weather is behind it rather than any failing on your part. Once you can tell summer scorch from the two leaf-spotting fungi, you'll know whether to reach for the hose or the rake. Match what you see below, then act calmly before it spreads.
Crisp, browned leaf edges when summer turns hot
Take heart, because those dry edges are just leaf scorch, and it happens when a tree in a hot, bright spot can't drink up water fast enough to keep its leaves plump. Young trees with shallow roots notice it first, and they bounce back once you help them. Water deeply through the dry weeks, tuck a 2 to 3 inch (5 to 8 cm) mulch ring around the base, and offer a bit of afternoon shade where the sun is fierce.
Fix:
- Provide deep, regular watering during heat and drought
- Apply a 2-3 inch organic mulch layer to conserve soil moisture and keep roots cool
- Site in partial afternoon shade in hot climates
A soft white dusting spreading over the leaves
Don't worry too much when you spot that pale film, because it is powdery mildew, a fungus that settles in on humid days, in deep shade, and where crowded growth keeps the air still. It may pucker a few leaves, but it seldom does any lasting damage. Open the canopy so air can breeze through, pick off the worst leaves, and only turn to a labeled fungicide if things really get away from you.
Fix:
- Improve air circulation by thinning and proper spacing
- Remove and dispose of affected foliage
- Apply a labeled fungicide if infection is severe
Little angular brown to purple spots freckling the leaves
Those dark-rimmed flecks are septoria leaf spot, a fungus that tends to show up later in the season after the leaves have stayed wet for a good while. It marks the leaf with spots rather than browning the whole edge, so it is easy to tell apart from scorch. Gather up and bin the fallen leaves so the spores can't overwinter, keep water off the foliage, and only treat with a labeled fungicide if the tree begins dropping leaves in a hurry.
Fix:
- Rake and dispose of fallen infected leaves
- Avoid overhead watering and wetting foliage
- Apply a labeled fungicide only if defoliation is significant
Toxicity
Here's some genuinely reassuring news. Kousa dogwood is non-toxic to pets, livestock, and people, and its ripe pinkish-red fruit is actually good to eat. There's no part of this tree you need to fence off or fret about a curious pet sampling.
Safe for
People · Cats · Dogs · Horses · Rabbits · Livestock · Birds
Cats Safe
You can relax with a cat around this tree, since none of it is toxic to them. A curious nibble on a leaf might leave a cat with a passing tummy upset, the same as any non-food plant, and it clears on its own.
Dogs Safe
Feel at ease if your dog explores the leaves, bark, or a dropped fruit, because there's no real danger in it. The worst a big mouthful might bring is a little short-lived upset that settles by itself.
Horses Safe
Horses are perfectly fine around this tree, foliage and fruit both. You have no reason to fence it away from a paddock.
Rabbits Safe
Rabbits can nibble the leaves without harm. As with any fresh green, just ease it into their diet so a sudden switch doesn't upset their digestion.
Livestock Safe
Cattle, goats, and sheep can graze happily around it, since the tree holds nothing that would trouble them.
Birds Safe
Birds love the ripe fruit and carry the seed off for you. It's a friendly food source, not a worry.
People Safe
You can enjoy the ripe pinkish-red fruit yourself, sweet and soft inside, and the rest of the tree is harmless. Most folks simply leave the thin skin and gritty seeds behind.
No special handling required; ingestion of plant material may rarely cause mild, transient gastrointestinal upset as with any non-food plant.
Varieties
Most kousa dogwoods you'll find for sale are named selections, chosen for their flowers, foliage, or toughness. These are the ones worth getting to know by name.
Milky Way
If you want a reliable show, this heavy bloomer, often listed under var. chinensis, covers itself in creamy-white bracts and then rewards you with a generous crop of fruit.
Wolf Eyes
A gentle, slow grower with green leaves edged in clean white, this one is a comforting choice for a smaller garden that could use some brighter foliage.
Satomi
For a softer look, this selection trades the usual white for warm deep pink to rose bracts.
Cornus × rutgersensis (Stellar series)
These forgiving Rutgers hybrids of Cornus florida and Cornus kousa, including Aurora, Constellation, and Stellar Pink, were bred to shrug off anthracnose and borers so you can worry less.
How to propagate
You can grow more kousa dogwood in several ways, from slow and variable seed to the easygoing layering trick that asks almost nothing of you. Which path suits you depends on whether you need an exact copy of a named tree.
SeedModerate
Sow cleaned seed in fall or after cold-moist stratification in late winter. · Several years to reach flowering size
Clean the pulp away from the seed, then either sow it in fall or give it a cold-moist stratification before sowing in late winter, which is what nudges it awake to germinate. Go gently on yourself and be patient, because a seedling needs several years to reach flowering size. Just know that seedlings come up variable, so they won't reliably match the parent tree.
Stem cuttingsModerate
Take softwood to semi-hardwood cuttings in late spring to summer. · One growing season to root and establish
Take softwood to semi-hardwood cuttings from late spring into summer, dip them in rooting hormone, and keep them under mist. Happily, they root over a single growing season, and kousa cuttings take more willingly than those of many other trees, so this is a kind place to start.
GraftingDemanding
Graft named cultivars onto seedling rootstock in late winter or summer. · One to two seasons to establish union
This is the trickier route, done by grafting or budding a named cultivar onto seedling rootstock in late winter or summer, so give yourself grace if it takes practice. The union knits together over one to two seasons. It's how nurseries keep cultivars true to type, since seed-grown offspring simply won't be.
LayeringEasy
Layer low flexible branches in spring. · One to two growing seasons to root
The kindest method for a home gardener is layering, where you pin a low, flexible branch to the ground in spring and let it root on its own. Give it one to two growing seasons, then simply sever it and move your new plant. You really can do this one.
Myths
Kousa dogwood catches anthracnose and borers just as badly as the native flowering dogwood.
You can put that fear aside, because Cornus kousa holds up far better against dogwood anthracnose and the dogwood borer than Cornus florida does. This is the tree to reach for where anthracnose has been trouble before, which is just why it comes so highly recommended as a stand-in.
The red raspberry-like fruit is poisonous and shouldn't be eaten.
Rest easy, since the pinkish-red fruit is entirely safe to eat, soft and sweet once it fully ripens. Birds and other wildlife enjoy it too, so it kindly serves as both a snack for you and a draw for the garden.