How to Plant and Grow a Quaking Aspen Tree

Quaking aspen trees are native to the cool mountain regions of North America, where they enjoy cold winters and cool summers. In nature, they are usually found growing above a 5,000-foot elevation. They grow best in their native habitat. When planted in urban and suburban landscapes, quaking aspen (Populus tremuloides) tends to languish. In these environments, they are short-lived, messy trees with brittle wood that creates litter, but their outstanding yellow fall color, white bark, and leaves that flutter in the slightest breeze have earned them a following.

Where to Plant a Quaking Aspen Tree

Plant a quaking aspen tree in an area with moist, well-drained soil and bright light. This tree doesn't tolerate shade or dry soil. It is cold hardy in USDA Zones 2–6. Quaking aspen trees are good choices for fast-growing windbreaks or mass plantings and as showy landscape specimen trees in large yards. Select a space that can accommodate a tree that reaches 40-50 feet and 20-30 feet wide at maturity. It grows about 5 feet a year.

How and When to Plant a Quaking Aspen Tree

Plant a quaking aspen tree in early spring so it has time to build a robust root system before winter arrives. Dig a hole that is the same depth as the root ball and twice as wide. If the soil is poor, amend it with organic matter or compost. Take the tree out of its nursery container (or remove any burlap or other covering if it is a balled and burlapped tree). Place the tree in the hole so that the top of the root ball is level with or slightly higher than ground level, adding soil to the bottom of the hole if needed for the correct height. Backfill the hole halfway with the removed soil, and water it to remove any air pockets. Fill the rest of the hole with soil and press down lightly with your hands. Water the tree.

To plant a windbreak or screen of quaking aspen trees, plant them about 10 to 12 feet apart.

Quaking Aspen Tree Care Tips

Light

A quaking aspen tree grows best in full sun, although it tolerates some shade.

Soil and Water

Quaking aspen trees prefer moist, well-drained soil but adapt to most soils as long as they drain well. Water the tree every week or two to keep the soil moist. In winter, water the tree weekly unless snow falls.

Temperature and Humidity

These extremely cold-hardy trees thrive in high-mountain environments. They need a cold winter and cool summer to look their best. Quaking aspen doesn't handle high humidity well and doesn't flourish in extremely humid areas like the Deep South.

Fertilizer

There is no need to fertilize a quaking aspen at planting time if the soil contains (or was amended to contain) organic matter or compost. Thereafter, fertilize the tree in early spring with a balanced, slow-release, granular fertilizer following the package directions.

Pruning

Any pruning to a quaking aspen tree is best done in winter while the tree is dormant. However, it doesn't need much pruning. Remove dead or damaged limbs and any low-growing limbs if the tree grows where people walk under it.

Pests and Problems

In its ideal setting, a quaking aspen tree is relatively healthy, but those growing in suburban or urban areas are likely to struggle with pests that include aphids, spider mites, caterpillars, borers, and scale. Although Bt (Bacillus thuringiensis) is effective against many of the tree's pests, it is almost impossible to treat an entire tree. A professional may need to be brought in for the job.

How to Propagate a Quaking Aspen Tree

Quaking aspen trees spread through their root systems. They tend to put up suckers that many homeowners find annoying. The easiest way to propagate a quaking aspen tree is to dig up one of the suckers, complete with roots, in early winter to early spring on a frost-free day and replant it right away in a new location.

If there are no suckers, portions of the root can still be used for propagation—if you can locate them. The roots run horizontally under the soil. Move the soil aside and locate a root that is about a half-inch in diameter. Cut a 4– to 6-inch section of the root with garden pruners and dip it in rooting hormone. Lay the root section lengthwise in a shallow container of potting soil or garden soil and cover it with a layer of compost. Place the container in a warm place. Roots should form within four weeks and suckers not long after that. The small trees and a section of root can be repotted into containers until planting time arrives.

Quaking Aspen Tree Companion Plants

The shallow roots of quaking aspen trees compete with other plants for moisture and nutrients, so companion plants benefit from being drought-resistant. Among the plants that make good companions for this lovely tree are those with silver foliage that contrasts nicely with the tree's dark green spring and summer foliage.

Artemisia

Artemisias are grown primarily for their silver foliage. These plants come in many different foliage shapes, sizes, and heights, and they add texture and subtle color to gardens, containers, and borders. Artemesias enjoy full sun and are drought-tolerant.

Catmint

Fast-growing catmint forms tidy little mounds of neat new foliage in spring. The plants quickly grow outward and set their buds for the rich purple blooms that explode into color in early summer. The show is spectacular and lasts for weeks. It grows in full sun or part sun and is drought-tolerant.

Coral Bells

Low-growing coral bells plants come in a rainbow of colors and are extremely low-maintenance. Coral bells thrive in mountains and woodsy areas, so they are right at home planted under a quaking aspen. Full sun fades the foliage of some varieties of coral bells, so the plant appreciates the partial sun found under the tree.