How to Keep Trees Healthy This Fall

Canadian winters are harsh. If you want the trees in your garden to successfully withstand the frigid temperatures, ice, and snow, you need to give them some help. Some extra care in the fall can help prepare them for the chilly months ahead, ensuring strong growth come spring.

This fall tree care checklist outlines essential steps for maintaining healthy trees as fall turns into winter. We take you through the entire tree care routine, from top to bottom—literally.

Check for Diseases and Pests

Before you invest time in fall tree care, give your trees a once-over for signs of pests and disease that could be killing your trees. In Alberta, Canada, common issues include bronze leaf disease, western gall rust, and Dutch elm disease.

Further, keep an eye out for mushrooms around the base of the tree. These can attack roots, causing decay and making them unstable. If you notice mushroom growth, you may be overwatering your trees.

Some pests and diseases can be eradicated, while others may require cutting the entire tree down. This will help protect the surrounding trees, keeping the issue from spreading. A tree care professional can advise on the best course of action.

Trim Branches

Weak or dying tree branches are a hazard, especially in winter when the weight of snow and ice can cause them to come crashing down. Have a professional tree trimmer remove unsafe, diseased, or dead limbs.

This will help protect your property and the people and pets on it. Tree trimming also helps to create an excellent shape, paving the path for a thick, lush crown of greenery come spring. Branches should be trimmed close to the trunk so that no stump is left behind.

Sometimes larger, older limbs on a tree may be less stable. While they don’t necessarily require cutting, they should get some extra help to withstand winter. A certified arborist can help, using cables and braces to help give weak branches and lengthy limbs some added support.

Protect Tree Trunks

Tree trunks are susceptible to a few threats in winter. First, if you live in an area where deer are prevalent, beware that they may nibble on tree trunks or use them to smooth their antlers. This can result in strips of tree trunks coming off.

To keep deer away, build a barrier around the tree’s trunk to ensure the animals can’t reach it. Another option is to use a protective tree wrap. A simple mesh or plastic guard will do. Other options include burlap or chicken wire.

Sunscald is another threat for trees in the winter. This occurs when the tree’s bark gets hot during the day due to sun exposure and then quickly freezes at night. To keep this from happening, use a plastic tree guard, wrapping it around the trunk.

Feed the Soil

Your trees get nutrients from the soil that help them grow strong and sustain themselves throughout harsh wintry conditions. Make sure they’re getting the fuel they need by applying a fresh dose of fertilizer in the autumn.

Look for a slow-release fertilizer, which will release nutrients into the earth over time, mimicking nature’s organic decomposition process. This ensures that tree roots have consistent access to nutrients throughout the months to come.

Depending on the quality of your soil, you may want to aerate before fertilizing. Aeration involves removing plugs of earth from the ground, leaving holes behind. This makes it easier for oxygen, water, and fertilizer nutrients to penetrate the soil and reach the underlying roots.

Add Mulch

In cold weather, mulch protects roots from frost. It also deters critters from digging around your tree roots. Further, it can help retain moisture in the soil, regulate the temperature, and minimize the risk of soil compaction. Opt for organic mulches like wood chips, shredded leaves, or straw.

Spread the mulch around the base of the tree, ensuring it’s about five centimeters thick. Make sure to leave a space of about seven centimeters around the bottom of the trunk. Otherwise, the mulch may retain too much moisture around the trunk, causing rot.

Mulching should be done before the ground freezes. However, if you’ve already missed this deadline, don’t stress. Go ahead and take care of your mulching anyway. It’s better than not doing it at all!

Minimize Your Irrigation

In winter, trees go dormant and cease active growth. As a result, they need fewer nutrients and water to survive than they would in summer. Further, in fall and winter, cooler temperatures and less sun mean that the soil doesn’t lose moisture as quickly.

All of this means you can reduce irrigation in the fall and winter. If you have a built-in irrigation system, turn it off to avoid flooding. The soil should be cool and moist to the touch but never soaked (unless it’s just rained).

Further, make sure to winterize your irrigation system if you have one. If water is left in the sprinkler lines, it will freeze and expand when the temperature drops. This can cause cracks in the lines, damaging your system.

Plant More Trees

Once you’re done caring for your existing trees, take the opportunity to reseed. Fall is an excellent time for planting, as the roots can establish themselves in the months to come and be prepared for a growth spurt come spring.

When planting new trees, leave sufficient space so that roots don’t compete for nutrients and water in the soil. Further, ensure that the trees aren’t near powerlines or other obstructions that could cause issues as they grow.

When selecting what trees to plant, make sure to choose species that will do well in the Canadian climate. Evergreens are one obvious choice. However, you have many other options beyond this. Even fruit trees like plum and apple can make it through the cold.

Clean Up

Now, there’s only one thing left to do: Clean up! Rake up leaves from your garden and remove them. Allowing them to fester on the lawn increases the risk of mold or mildew growth. To speed things up, rake all your leaves onto a big plastic tarp and then bundle it up to remove them. 

What to do with the leaves? If you have a compost pile, throw them on. Flip the pile once per month to allow oxygen in, which helps speed up decomposition. You can also shred them to use as mulch or fertilizer in the future.

Make sure to remove any lawn care, tree trimming, or other garden equipment from the yard when you’re done. Allowing items to sit on the lawn in winter can cause the underlying grass to turn brown and die. You don’t want your fall tree care to damage other parts of your yard.

The Final Word on Fall Tree Care

Preparing your trees for winter takes some time and effort. As you can see, it’s not a one-day job. Leave at least a week for your fall tree care, so you aren’t stressed about time. Advanced planning will also help you beat the first ground freeze.

However, when you’re dealing with harsh Canadian winters, it’s a must! Your efforts will be worth it when you can start the spring with fresh, lush, healthy growth. The fall tree care checklist above can help you get started.