How to Plant, Grow, and Care for Smoke Trees

One of the most intriguing landscape ornamentals, smoke trees have an ethereal aesthetic that evokes a sense of drama and mystery in the garden. The billowy hairs that dangle from the smoke tree’s wispy spent flower stalks resemble a smoke-like puff, giving this tree its iconic shape and name. 

This large multi-stemmed woody shrub or small tree grows to 15-30 feet and adapts to many landscapes, from poor soils to polluted inner city landscapes. While the smoke tree genus includes seven distinct species, the most common are the North American native smoke tree (Cotinus obovatus) and the non-native European smoke tree (Cotinus coggygria). Both species offer unique varieties and attributes and thrive with similar care. 

With proper site selection and moderate maintenance, these striking hazy-hued trees are perfect for borders, woodlands, and individual specimen plantings. Let’s dig into everything you need to know about this lovely ornamental.

History and Cultivation

Smoke trees, sometimes called smoke bushes, mist trees, or cloud trees, are a group of large flowering shrubs or small trees in the Cotinus genus. The genus includes seven unique species, all sharing the distinctive wispy, airy-looking flowers that add exceptional fall color to the garden. When in bloom, the small trees look like billows of hazy smoke.

Where Does Smoke Tree Originate? 

The iconic ornamental smoke tree has two main origins: America and Eurasia. The most commonly landscaped tree comes from southern Europe and central China, but a related species is native to Eastern North America. 

All members of the Cotinus genus have the signature fluffy, smoke-like dried flower clusters. They are known for their magnificently vibrant fall leaves and the fish-scaled appearance of their bark that stands out in the winter. In North America, the heartwood of the smoke tree was traditionally used by Natives as a yellow or orange dye.

American vs. European Smoke Tree

The common smoke tree, Cotinus coggygria, is native to Eurasia and widely cultivated as a landscape plant in the United States. This species was introduced as early as 1656 and remains commonly available in most mainstream nurseries around the country. 

Plant breeders have developed dozens of colorful cultivars with leaf shades ranging from golden, green, and purple, and flowers in hues of pink, mauve, red, purple, and bronze. Most cultivars transform to stunning hues of yellow, orange, or red in the autumn. The Eurasian species is dioecious, meaning male and female plant parts grow on the same tree. The smoke display is the same for both male and female flowers.

The American smoke tree, Cotinus obovatus, is native to the United States and grows wild in rocky soils from central Texas to Tennessee. It is more cold hardy and larger in stature than the Eurasian species, but its flowers tend to be smaller and less showy. The American species is also dioecious, which means there are separate male and female trees. The male plants have a “smokier” appearance.

Propagation

Stem cuttings are the cheapest way to propagate smoke trees, but they can also be grown from bare-root trees or seeds.

Cuttings

Propagation with cuttings is the easiest and most economical way to grow a lot of plants from a single specimen. If your friend has a smoke tree in their yard, ask if you can take some cuttings to grow your own. This method involves collecting sections of healthy fresh stems in the spring and encouraging them to root in a rooting medium.

Take semi-hardwood cuttings in late summer or fall. This wood from the current season’s growth is not the fresh, green new growth of spring softwood, nor is it the mature older wood closer to the center of the tree. Find semi-hardwood stems where a tiny twig meets a larger branch or the trunk. It should be somewhat pliable yet firm, with full-sized leaves and moderate woodiness.

Scientists confirm that biostimulators and root hormones like auxin improve propagation success. You can buy powdered or liquid rooting hormones at most garden nursery stores. If using a rooting hormone, pour a small amount into a lid or shallow dish to dip your cuttings. You don’t want to contaminate the larger container.

Bare-Root Trees

Most nurseries stock bare-root smoke trees of varying sizes. You can purchase a juvenile tree around two feet tall or pay more for a mature specimen. Either way, the plant will be shipped with bare roots wrapped in a bag. This means the soil has been removed from the root zone to make it lighter weight and easier to transplant. As soon as you receive a bare-root shrub, it’s important to rehydrate the roots by soaking them in a bucket. Then, plant it in the garden immediately.

Bare-root trees are the most convenient way to establish woody perennials, but they are more expensive than propagation by cuttings and trees. When planting, be careful to dig a hole at least twice as wide and the same depth as the root ball so the soil is loose enough for young roots to reach downward. You can also stretch lateral roots out horizontally to promote rapid establishment. 

Seeds

Growing this fluffy tree from seed is not as simple as you might think. While the process can be rewarding, it also requires extensive patience. Seeds can take weeks or months to germinate, and several years to mature. You can collect your own seeds from mature trees in the autumn, or purchase seeds online. 

Cotinus seeds have a very strong internal dormancy and a super thick seed coat designed to protect them from rugged conditions in the wild. This means they can germinate very erratically or slowly in domestication. Research shows that seed germination is higher if the seeds are treated with sulfuric acid or heat-treated in boiling water to break down the extra hard seed coat. 

Planting

The best time to plant a smoke tree is in the spring around your last frost date. This gives the tree plenty of time to adjust and establish before its first winter. If you purchase a larger container plant, it can also be transplanted in early summer. 

How to Transplant 

Cotinus species grow most abundantly in open, sunny positions. Partially shaded areas will alter the hue of the leaves. For example, purple-leaved cultivars may look more brown, while yellow-leaved varieties can turn lime green. If you want the smoky aura around this tree to appear like it does in the nursery catalog, be sure to transplant in an area that is not shaded by larger trees or structures.

Avoid fertilizing at the time of planting. These plants grow slowly and do not require additional nutrients.

Spacing

Smoke bushes come in a diversity of sizes. Larger cultivars can grow over 15 feet tall and require at least 10 feet of space from neighboring plants or structures. If you want to grow the tree as a central specimen, provide a 12-15 foot circumference from the trunk. Smaller varieties can be grown in groups or hedges with four to five feet between them. 

How to Grow

These deciduous large shrubs or small trees are ideal for adding seasonal interest to your landscape. Their smoke-like flower clusters add the signature hazy backdrop to garden beds all summer long, and their stunning autumn show makes them stand out when leaves are changing. In the winter, smoke trees lose their leaves and display intriguing bark and wispy structural stems. Tending the trees is easy as long as you properly prepare the planting site.

Light

Full sunlight is ideal for Cotinus species. Most varieties need six to eight hours of direct sunshine daily to grow to their fullest potential. Partially shaded specimens will still flower and add whimsical hues, but their colors may look different from the varietal descriptions, and the flowering abundance will be reduced. Avoid planting in deep shade, or the foliage will look sparse and leggy.

Water

Once established, these shrubs are moderately drought-tolerant but appreciate occasional watering during prolonged dry periods. If you don’t have available irrigation in the part of your yard where you intend to plant smoke bush, be sure to plant the native species, as it can withstand more dry weather. 

Water regularly throughout the first growing season to promote a deep, strong root system. The soil should be consistently moist but never soggy. Deep, infrequent watering is better than shallow, frequent watering. In other words, adding a lot of water slowly in one session is better to penetrate deeper into the soil profile.

A layer of mulch like shredded bark or wood chips conserves moisture, suppresses weeds, and adds a pleasant aesthetic. The mulch will prevent the soil from drying out too quickly. 

Soil

Drainage is the main soil attribute these trees need. They are not picky about pH or soil texture, as long as the soil is well-drained and water can move through the roots.

Planting smoke bushes in compacted or poorly drained soil can lead to waterlogging, root rot, and plant failure. Amend with sand, compost, or peat moss to increase drainage. The trees tolerate slightly acidic to neutral pH between 5.5 and 7.0.

Climate and Temperature

Most Cotinus trees are adaptable throughout the U.S. in growing zones 5 through 8. Some varieties of the American smoke tree can grow in zone 4. The plants don’t mind hot summers and moderate frosts as long as they aren’t exposed to prolonged subzero temperatures. 

For cold climate gardens, you may need to wrap the trunks of non-native species in burlap and apply a deeper mulch to insulate smoke trees through harsh winters. In warmer regions, the trees need more moisture and appreciate some afternoon shade. Take advantage of microclimates throughout your landscape, such as south-facing walls that can provide more heat, or east-facing beds that receive cooler shade in the afternoons. 

Fertilizing

These smoke-like ornamentals do not need a lot of fertility. The native species can get by on solely soil minerals and organic matter. You can fertilize in the early spring to promote more vigorous growth but a slow-release organic fertilizer is best to avoid fertilizer burn. Over-fertilizing is a risk because smoke trees with excessive nitrogen grow excessive foliage and fewer flowers, leading to a less smoky appearance. 

Avoid fertilizing in the fall, as this can stimulate trees to develop late-season growth. Newly grown twigs are subject to frost damage because they don’t have enough time to harden off before the harsh weather of winter.

Maintenance

Cotinus trees don’t need much pruning or maintenance. It is helpful to cut back diseased or damaged branches in the winter or early spring while the plant is dormant. You can also use this opportunity to shape the tree or shrub in a desirable form. Pruning away lower branches can promote a more tree-like growth rather than the natural multi-stemmed shrubby shape. However, you should avoid heavy pruning, as it may reduce flower production.

Young trees may need to be staked to keep them upright in windier areas. The first years of planting are the most delicate for smoke trees, so be sure to protect them from harsh rains or extreme temperatures.

Varieties

The Cotinus genus includes several species with dozens of varieties and cultivars in rainbow hues. Here are the most popular and striking for a home landscape:

American Smoke Tree (Cotinus obovatus)

Sometimes called Texas smoke tree or Chittamwood, this native species is ideal for low-maintenance landscapes where you want to support local wildlife. This species grows wild in parts of the Southeastern United States and tolerates limestone bluffs, slopes, and dry rocky soils. It is the most resilient of all the varieties on this list.

It has larger leaves than the Eurasian cultivar and usually produces 6-10” clusters of flowers that turn into airy purplish-pink hairs that make the tree look smokey. The sap has a distinctive, strong odor, and the wood produces a striking yellow dye. 

C. obovatus ‘Flame’

This domesticated cultivar of the American smoke tree has been bred for fiery orange and red fall colors. The spent flowers have the signature large, puffy appearance. 

C. coggygria ‘Royal Purple’

‘Royal Purple’ is probably the most popular landscaping variety. Developed from the Eurasian species, this cultivar has dark purple foliage that turns scarlet-red in autumn. The wispy flowers have a tinge of pink that looks really beautiful in the backdrop of a white and pastel-themed flower garden.

C. coggygria ‘Golden Spirit’

Another Eurasian cultivar, ‘Golden Spirit’ has bright yellowish-gold leaves that turn red and orange in autumn. The contrast of creamy white flower clusters looks unique against the golden foliage backdrop, almost like an angelic aura surrounding the shrub. 

C. coggygria ‘Grace’

This popular urban bush has greenish-blue leaves with a striking diversity of fall colors, including orange, gold, yellow, and red. The pink flowers are delicate, and add a Dr. Seuss-inspired fluffiness to the landscape. ‘Grace’ is tolerant of pollution and does well in urban or suburban yards.

C. coggygria ‘Daydream’

The peachy-yellowish hue of the hybrid ‘Daydream’ smoke bush is whimsical and mysterious. This hybrid variety grows densely and produces maroon-hued flowers. The fall foliage ranges from gold to orange to reddish-purple. This is the perfect specimen and can be pruned to grow as a single-trunked tree.

Design Ideas

Many plants grow well in the same conditions as smoke trees, complementing their form without overshadowing their hazy glory. Great companions include:

• Spirea
• Viburnum
• Ninebark
• Ornamental grasses
• Weigela

Pests and Diseases

The Cotinus genus is relatively problem-free, but these issues occasionally pop up. Here is how to deal with them:

San Jose Scale

If you notice the sap-sucking pest forming scale-like colonies on the branches of your smoke tree, it’s important to take action. San Jose Scale is a major pest of fruit trees and can kill entire limbs with large infestations. 

The mobile scales are small and yellow, while the immobile scales anchor in place and turn tannish-white. They look like an unfortunate outbreak of hives or pimples on the tree branch. Unfortunately, they develop a thick waxy layer to protect themselves, so they can’t just be wiped off. On the bright side, their lack of movement makes them easier targets for beneficial predators like ladybugs and lacewings.

As soon as you notice an issue with scale, apply insecticidal soap or horticultural oil to the affected branches and monitor for several weeks to ensure the pests die back. In smaller infestations on smaller trees, pop them off the tree with a cotton swab or Q-tip soaked in alcohol.

Leaf Spot

In rainy, warm climates, smoke trees can be prone to a fungal infection called leaf spot. The rusty-looking blotches are unsightly and can inhibit the tree’s ability to photosynthesize. The best solution is to prune the tree to improve air circulation between branches. Avoid overhead sprinkler watering and ensure wide spacing between plants.

Verticillium Wilt and Rust

Brown or scorched-looking leaves on a smoke bush are usually a sign of another fungal infection called Verticillium wilt. The wilting or browning is sometimes lopsided, with only one-half of the tree displaying symptoms. Smoke trees growing in poorly drained soils are the most prone to wilt disease, so it is very important to loosen the soil and mend it thoroughly at the time of planting. 

Once the roots succumb to wilt and the branches are noticeably drooped, there isn’t much you can do except remove affected branches and dig into the ground to loosen the soil. You can try transplanting the smoke bush into a better-drained area and prune away infected roots while the root ball is above ground.

Rust is a fungal disease that causes dark brown spots that lead to light brown leaf tips. The pathogen Pileolaria cotinicoggygriae remains in leaves that fall off the tree. The best treatment for smoke tree rust is the removal of fallen leaves. Outside of that, experts recommend systemic fungicides, but the issue may not be severe enough to require them.

Plant Uses

Smoke trees are primarily used as landscape specimens or border plants mixed with other perennial ornamental shrubs and grasses. The fluffy appearance makes them a great screening hedge throughout the growing season, but they lose their leaves in the winter. They are most often planted for their dazzling fall color. 

Historically, the bark and wood were used as a bright yellow natural dye. The plant is not considered edible.

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