Kousa Dogwood: Comprehensive Guide to the Japanese Dogwood

Despite a decline in popularity among gardeners due to a fungus outbreak, a suitable alternative, in the form of the Kousa dogwood (Cornus kousa) native to North America, has been discovered by some.

Even if you have no prior experience with dogwood trees, you’ll find that this Japanese native is quite easy to grow and very rewarding in terms of decoration and beauty.

How many years does it take a Kousa dogwood to bloom? Kousa dogwood takes from 5 to 7 years before it starts to bloom. The reason for that long wait is that the tree itself takes its time to develop its root system and foliage before the blooms appear. However, once it starts flowering, the bloom will keep appearing like clockwork every spring.

Like many other imported trees that are not native to North America, it takes a little extra care and some precautions to ensure that the Kousa dogwood will grow successfully in your yard.

Read more to find out how to grow and care for this attractive tree.

The Kousa dogwood is just one of the many popular dogwood varieties. Learn more about the best options for your landscape in my article, The Best Dogwood Varieties.

Kousa Dogwood

Native to Japan, Korea, and China, Kousa dogwood is a great alternative to the local dogwood species that are prone to fatal fungal infections.

The tree has a small, compact size and a moderate growth rate. It’s a late bloomer, but once it starts flowering, its bright pink, red, or white blooms keep showing up without fail.

Botanical nameCornus kousa
Mature height15-30 feet
Mature width15-30 feet
Growth rate12-24 inches per year
Light preferencesFull sun to partial shade
Ideal soilRich, loamy, well-draining soil
Watering needsConsistently moist soil for young trees, 1 inch of water weekly for established ones
Bloom timeMay to June
Bloom color & fragranceWhite, pink, red; light floral scent
Fall foliageReddish-purple to scarlet 

General Appearance

The Kousa dogwood is a showy tree that has as much spread as height. It averages from 15 to 30 feet tall and the same in width.

The dark-green leaves average 2.5 inches long and taper toward the end. The tree has an upright growth habit, and when the flowers open in early spring, it becomes the center point of attraction.

It has edible fruits each about 2 inches in diameter that ripen to pink to red by the end of summer.

Seasonal Color

In mid-spring, the leaves emerge with a yellow-green color, but they soon turn into dark green around the time flowers open up.

In the fall, the leaves turn reddish-purple to scarlet. This fiery colorful show lasts anywhere from 3 to 5 weeks before the tree sheds its leaves for the winter.

Growth Rate & Mature Size

Kousa dogwood has a moderate growth rate for a tree of its size.

The small varieties of the tree average about 15 feet tall and the same in width at maturity. These small trees will grow about 12 inches per year.

On the other end of the spectrum, some Kousa dogwoods can grow to 30 feet tall and wide. Those trees will average about 24 inches in growth a year.

However, factors like growing conditions and diseases can affect these growth rates.

Blooms

Kousa dogwood is a showy tree. One month after the leaves emerge, flower buds start to open. They vary in color based on variety and can be pink, red, or white.

The tree will only start blooming once it has established, which may take from 5 to 7 years, but you can expect blooms every spring for many years to come after that.

A Kousa dogwood blooming happily.

Fall Foliage

Even after the blooms have faded and the ripe berries have brightened your yard with a pop of red color, the Kousa dogwood still has one more colorful show in store.

In the fall, the leaves turn reddish-purple to scarlet, and when the tree catches the setting sun, it looks like it’s on fire. This festive show of colors lasts for 3 to 5 weeks on average.

Hardiness

Although Kousa dogwood with all its varieties is not native to North America, it has adapted well to moderate Growing Zones.

It can tolerate different types of soil and will thrive in partial shade when full sunlight is not available.

The tree prefers slightly acidic soil. High pH levels can impact its foliage and blooms. Although it should come through a dry spell with minimal impacts, this tree prefers consistent soil moisture.

Kousa Dogwood Growing Conditions

Kousa dogwood, like any other flowering and fruiting tree, requires certain growing conditions to thrive.

Choosing the right spot in the garden and making sure that the tree is getting the right amount of sunlight and water are some of the vital requirements for the non-native Kousa dogwood.

Here’s what to keep in mind before planting the tree:

Grow Zones

Kousa dogwood prefers the moderate Growing Zones between 5 and 8.

It can tolerate some cold winters and the occasional above-average summer heat, but trying to plant the tree in hot Zones above 8 or cold ones under 5 has proven to be unsuccessful in the past. 

Sun Requirements

The sun-loving Kousa dogwood prefers direct exposure to full sunlight. The flowers have richer colors when they get between 6 and 8 hours of sunlight daily.

The sun is also crucial for the ripening of the tree berries, so make sure that the tree isn’t growing under the shadow of a larger tree or a tall building. That said, the tree can still grow successfully in partial shade.

Soil Preferences

This dogwood needs rich and well-draining soil. You’ll need to amend the soil by adding plenty of organic materials before planting the tree.

The soil needs to be slightly acidic for dense foliage with deep colors. If the leaves are pale green, then the soil might not be acidic enough.

Test the soil pH regularly, and keep it between 6.0 and 7.0.

Kousa Dogwood Maintenance and Care

Once you have the Kousa dogwood tree growing successfully in your garden, your next task is to keep it watered, fed, and in good shape.

That means you’ll have to pay extra attention to watering in particular as well as pruning.

Watering

Kousa dogwood trees prefer soil that is consistently moist, especially during the growing season, but there’s a fine line between moist soil and saturated soil.

The young Kousa dogwood needs more water than an established one, and the amount of water you need to give the tree depends on the weather conditions.

On average, the tree will need between 1 and 1.5 inches of water a week, but if the weather is hot and dry, up to 2 inches a week might be needed to maintain the moisture levels in the soil.

Fertilization

Since the Kousa dogwood thrives in rich soil, you’ll need to feed it plenty of organic compost and aged manure.

You can also use a balanced fertilizer for fruit trees or for acid-loving plants. I’ve seen great results with this blend.

The best time to apply the fertilizer is in the spring before the first signs of growth. Keep in mind that during the first year, the tree doesn’t need any fertilizing. 

Pruning

As a small and compact tree, your pruning of the Kousa dogwood should mainly focus on keeping it in shape rather than managing its size.

Remove any dead, damaged, or diseased branches without hesitation.

You should prune the tree annually and only on an as-needed basis. Pruning should never remove more than 10 percent of the tree’s canopy and is ideally done in early spring while the tree is still dormant. 

A Kousa dogwood tree loaded with red berries.

Pests & Diseases 

Kousa dogwood is prone to many of the common pests and diseases that afflict other dogwood species. These diseases include botrytis, bacterial leaf scorch, septoria leaf spot, crown canker, and powdery mildew.

Among the pests that attack the tree, you might see the dogwood borer, Japanese maple scale, the oyster shell scale, leafhoppers, or calico scales. 

Landscape Uses & Wildlife Value

The Kousa dogwood tree adds color to any landscape. You can use it as the focal point in the garden or lawn or plant several together to fill a large space.

Since it has a small size, it’s best to keep it front and center of your design with larger trees in the back. As for the berries, wildlife such as squirrels, rabbits, and deer include them in their diet. 

Companion Plants

Many plants grow well with Kousa dogwood.

Try pairing your tree with:

  • Christmas fern (Polystichum acrostichoides)
  • Drooping laurel (Leucothoe fontanesiana)
  • Mountain laurel (Kalmia latifolia)
  • Mapleleaf viburnum (Viburnum acerifolium)
  • Pinxterbloom azalea (Rhododendron periclymenoides)
  • Wild geranium (Geranium maculatum)
  • Carolina allspice (Calycanthus floridus)

Where To Buy

You can often find Kousa dogwood at your local nursery. If it’s not available there, try one of the following online nurseries.

  • FastGrowingTrees.com: An excellent nursery that caters to a wide variety of Grow Zones. It offers many fruit and ornamental trees.
  • NatureHills.com: This nursery offers fruit and flowering trees along with bushes, perennials, annuals, and bulbs.
  • Arbor Day Foundation: An organization dedicated to planting trees where they’re needed most and inspiring people to appreciate trees more.

Closing Thoughts

Kousa dogwood is a showy, compact tree that is a delightful alternative to the dogwood species native to North America.

It comes from Eastern Asia and does well in Zones 5 to 8. The tree starts flowering after 5 to 7 years and will be a welcome addition to your yard.

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