Ample shade and cotton-like seeds are the two features that set cottonwood trees apart from other trees. It’s a tree that towers over many others in the garden and spreads its canopy far and wide. Found a lot in parks and public places, this is a tree that demands respect with its imposing presence.
In the wild, the cottonwood tree grows near ponds, riverbanks, and even riverbeds. But the reason this tree has gained a reputation as a landscaping tree is because of its phenomenal growth rate. Every year your young cottonwood tree will add 6 feet to its towering height. Pretty soon you’ll have a nice shade covering your garden, home, and the street as well. But like all trees, this one has its own set of issues and problems. This guide takes a good look at the cottonwood tree and explores it from every angle.
Advantages and Disadvantages of Cottonwood
If you have been following the other gardening posts here, you no doubt have noticed that every plant, tree, or shrub, comes with its own issues. Some are easy to plant but hard to maintain, while other require a complex process of sowing and planting. Granted, cottonwood trees have problems of their own, maybe more than other trees of their elk, but their positive side eclipses these negative points.
Some of the undeniable advantages of cottonwood trees include,
- Fast growth rate. Within a few years, the tree is already towering over the house and surrounding buildings.
- The flat leaves have a distinctive shimmer and rustle when the slightest breeze blows.
- In the fall, the foliage turns into a beautiful gold with various shades which when the sun falls in it literally glows.
- Due to its fast growth rate, the cottonwood tree is the ideal choice in areas prone to floods and erosions.
- It is also used in waterways as a natural filtration method that prevents the pileup of debris in bodies of water and sedimentation.
- The tree with its vast canopy acts as a natural windbreaker.
- The rich foliage and spread of the tree make it a great choice for landscaping.
As for the drawback, they are plenty as well.
- The major drawback of this tree is the cotton that holds the seeds. At best it’s a nuisance and at worst it can trigger allergies in some people. When it blocks air conditioning ventilators or floats in the pool, that can be a maintenance nightmare.
- The fast growth of the tree comes at a price. The quality of the wood isn’t up to snuff making the branches prone to falling and damaging properties.
- The tree has a shallow root system that tends to break the surface and cause problems on the sidewalk.
- In urban areas, the expanding root system of the cottonwood tree invades the septic system of the city and blocks it.
As we’ll see these are not the only upsides and drawbacks of the cottonwood tree. We’ll explore more of that complex tree later on. But for now, let’s see what cottonwood tree you can grow..
Varieties of Cottonwood Trees
The mighty cottonwood tree that you see in parks, next to ponds and rivers have two main species. These are narrow-leaf cottonwoods and plains cottonwoods. So let’s find out what each species has in store and why you would choose one over the other.
- Narrowleaf Cottonwood Trees (populus augustufolia): The young trees have a green and smooth bark that soon turns gray and veined as it matures. It has bright and shiny leaves that shimmer in the sun with a pale underside. Each leaf is 3 inches long and shaped like a lance. The trees bear fruit which is hairless and light brown. The egg-shaped fruits mature in the spring and split open to spread the seeds. The tree reaches heights of 60 feet in the right conditions especially when it grows in moist streams and coniferous forests.
- Plains Cottonwood Trees (populus deltoides): the greenish-yellow bark of the young tree becomes rough and dark gray as it gets older. The leaves are broad, glossy, and light-green in color. Each leaf is about 6 inches long and 4 inches wide. The fruits split open when ripe and cotton-like material comes out carrying the seeds. These are giant trees that can reach 190 feet when fully grown. They grow will with willows and near bodies of water.
Both species have a lifespan of about 30 years. Just watch out for any walls or structures near the tree due to the problems their expansive shallow root system tends to cause to sidewalks and fences.
How to Grow Cottonwood Trees
Even if you have little experience with gardening, there’s no doubt that you are well aware that growing a tree is no simple undertaking. This is not a patch of veggies or flowering plants that you can experiment with. The cottonwood tree is a giant of a tree that needs plenty of planning well in advance. So let’s go through the needed steps to plant this tree in your garden, lawn, or backyard.
- Check that the area you plan to plant the tree in has access to unrestricted sources of water. This could be underground shallow water, or areas that get flooded with water on a regular basis.
- Prepare your soil beforehand. You could use a tractor or a backhoe to turn the soil and give it enough time to air.
- Collect the cuttings of the cottonwood tree in late December and early January.
- Each cutting should be 4 to 5 feet long and 1 inch in diameter. Remove any leaves and make sure the cutting has no scars.
- Plant the cutting in the soil about 3 feet deep.
- Add shredded bark mulch to help the soil retain water and keep it well-drained as well.
- If you’re planting more than one cutting, make sure to leave enough space between each sapling. This is important when planting a fence or landscaping border.
- Water the soil well after planting the cuttings and keep it moist for the first few weeks until the roots grow.
- Use a well-balanced fertilizer and organic compost to encourage the growth of the tree once the first leaves show up.
Cottonwood Tree Care
One thing about the cottonwood trees, they grow so fast and they don’t bother you with their demands. The only two things you need to pay attention two are pruning and providing it with plenty of water.
Pruning and Maintenance
Before you know it, the tree you just planted last year is already taller than you with sprawling branches and leaves all over the place. The thing is, if you neglect this part and don’t do your due diligence, the tree will grow beyond your control and you won’t be able to prune it once it’s reached its full height and width.
Also, remember that pruning the young tree when the bark is still smooth and green helps the trunk become stronger and develop a robust structure. When pruning, remove any other branches that develop near the base so that you only have one trunk. Make your rounds throughout the year removing any dead limbs, broken branches, or diseased limbs. The same applies to crossing branches that could weaken the structure.
The other necessity for the growth and prosperity of cottonwood trees is water. They need plenty of water to grow and thrive. When the tree is still young and growing, you’ll need to either irrigate it like three times a week or plant it near a good source of water such as shallow underwater deposits. However, once the tree is established, you wouldn’t have to worry about that since the deep roots dip in the nearest sources of water.
Pests and Diseases
Now comes the time to talk about one of the biggest drawbacks of the cottonwood tree. That’s the huge amount of pests that get attracted to this tree. In general, you’ll often find yourself fighting off the following pests and diseases
- Gall aphids: they appear in the form of small bumps along the stem of the leaves. The bumps open in the spring releasing the insects that infest the rest of the plants and trees in their vicinity.
- Cottonwood leaf beetle: these small pests hibernate under the bark of the young cottonwood tree in the winter and come out in the spring. It feeds on the foliage and has the ability to strip the tree bare if you don’t intervene. Treat the tree with organic neem oil to get rid of this beetle.
- Canker fungus: this fungus spreads through unsterilized pruning tools. The infected areas look like soaked spots with a distinctive reddish-brown color. Prune off any infected branches and dispose of them safely.
- Heart rot fungus: as the name implies, this fungus makes its way inside the trunk through scars in the bark. There it proceeds to eat at the trunk and cause the heart of the tree to rot. If left unchecked, the tree will eventually die.
- Fungal leaf spots: you will notice this infection in the otherwise shimmering leaves and bright foliage. The fungus causes discolored spots in the leaves. If not treated, the fungus causes the leaves to drop and the tree to look bare.