All About Cottonwood Trees
Get past the fluff — and learn what you need to know about growing cottonwood trees.
A towering native, a cottonwood tree soars and spreads, growing more than 100 feet tall and almost as wide. It’s a cherished shade tree, often planted in parks. In the wild, cottonwood grows along rivers, ponds and other bodies of water. It also thrives in floodplains and dry riverbeds, where infrequent rains transform dry land into waterways.
Historically, cottonwood earned its place as a landscape tree because it grows rapidly, adding up to 6 feet a year. It’s also a favorite for shade, with the large spread helping to cast cooling shade over homes and streets. There’s a cottonwood for nearly any region, with different hardy types in Zones 2 through 9.
Why We Love Cottonwood
Fast growth and wonderful shade are reasons enough to cherish cottonwood, but these trees possess other qualities that make them worth planting. The leaves have flat stems, so they shimmer and rustle in the wind. The effect is eye-catching and distinctively attractive. The tree offers strong fall color, with leaves fading to glowing shades of gold.
In the wild, cottonwood is one of the fastest trees to colonize unplanted areas, making it a solid choice for areas prone to flooding and soil erosion. The National Forest Service uses it to stabilize streambanks and act as a natural waterway filtration system to reduce sedimentation. It tends to colonize and form groves that act as natural windbreaks. In areas with enough space, such as a ranch or acreage, a cottonwood makes a beautiful addition to a landscape.
The different types of cottonwood include:
- Eastern cottonwood (Populus deltoides) — grows in eastern U.S. and southern Canada
- Black cottonwood (Populus balsamifera) — grows west of the Rocky Mountains
- Fremont cottonwood (Populus fremontii) — grows from California east to Utah and Arizona and south into northwest Mexico
The Cons of Cottonwood
Of course, not everything about the cottonwood tree is perfect. For instance, the cotton that helps carry seeds on the breeze can be a nuisance, especially when it sticks to window screens, blocks air conditioning units or coats a swimming pool. There's a workaround, though. Cottonwood trees are male and female, and only the female types form seeds (and cotton). Look for the male ‘Siouxland’ variety, which grows 2 feet to 3 feet per year, and you’ll have a cottonwood tree minus the cotton.
The rapid growth that makes some folks cheer for cottonwood is also a negative, because the wood is brittle, leading to breaking branches and plenty of twigs to collect before mowing. As a cottonwood tree grows, large branches often break in windstorms, which can lead to property damage.
Because cottonwood trees are adapted to thrive in floodplains, they naturally have shallow root systems, so that as floodwaters recede, the roots can breathe and the tree survives. These same shallow roots wreak havoc with sidewalks and driveways. Roots also seek out moisture, invading sewer pipes and septic systems.
The Bottom Line on Cottonwood
Cottonwood makes a stunning tree — planted in the right spot. It’s a spectacular sight when it can grow unrestricted and welcome wildlife like roosting turkeys or eagles. A good place to grow cottonwood is away from structures, on a ranch, farm or in a park.
In a residential setting, it’s not the best choice. In fact, some municipalities ban the planting of cottonwood, and many gardening experts recommend removing cottonwood trees on residential properties. If you buy a home with a cottonwood tree, it’s wise to have it inspected by a certified arborist, who can assess the tree’s health and prune — or remove — as needed.