Step 1: Aerate & fertilize the soil.

When winterizing your garden, start from the ground up. Carefully loosen compacted soil around your plants. Doing this allows good drainage when the snow piles up. It also protects the roots of your tree or shrub from suffocation!

Next, fertilize trees and shrubs that aren’t in nutrient-rich soil. Choose a fertilizer suited for that specific tree. For example, if it’s one that you’ve recently planted, steer clear of using fertilizer with too much nitrogen since it can do more harm than good. When you buy your soil at a home and garden store, ask them what type of soil your specific trees and shrubs need.

Step 2: Insulate the roots.

After tilling and fertilizing the soil, focus on blanketing it for the season. Insulating your tree or shrub’s root system will protect it from the cold.

To winterize these root systems, spread a hefty layer of mulch on the ground as far as the tree’s branches spread. This creates a warm and cozy winter blanket and can prevent weeds from growing. Just ensure that the mulch doesn’t touch the tree trunk or pile up around the trunk in a dome. Aim for an even layer all around.

Step 3: Prune branches & bark.

Prune dead and damaged branches that could harm your trees during the winter. Completely remove any branches that clearly are dead or rotting—these provide food and shelter for unwanted pests. Next, lightly trim branches that will likely touch the ground under the weight of heavy snow. Branches that sit on the ground are far more likely to pick up moisture. That will cause rot and disease.

Remember, while you prune, you want to preserve as many healthy branches as possible. If you must make a cut, use a sharp, clean pair of shears. Instead of trying to remove the branch in one cut, clip the branch above and below the branch collar—the slightly bulbous area where the branch meets the tree trunk.

The Alberta Arborists have a helpful and detailed tree-pruning guide. Check it out when you winterize your trees.

Repurpose for the Season

If you are pruning evergreens, save some of the branches for your holiday décor!

Place freshly pruned branches in vases with water, or use twine and wiring to make a wreath to hang on your door. Use smaller trimmings as accents on holiday wrapping or put them in bowls with pinecones and ornaments as festive centrepieces. You’ll love that fresh and festive smell!

Step 4: Water your trees and shrubs.

Regularly watering your flower and vegetable gardens is second nature to Alberta gardeners…but how often do you think to water your trees? Just like the other plants in your yard, your trees need to stay hydrated! Watering them helps them get nutrients from the soil and keeps their root systems healthy.

When winter arrives, frozen soil prevents plants from drinking the water they need. Giving your trees and shrubs a few deep watering sessions before the first hard freeze will help them store up that crucial water. 

Consider the “5+5 rule” for winterizing newly planted trees: five gallons of water as a base, plus another five gallons for every inch of your trunk’s diameter.

Step 5: Wrap vulnerable trees and shrubs.

If you have younger or vulnerable trees and shrubs, wrap them before the first snow. You can use burlap or pick up tree and shrub wrap from the garden store. Wrapping protects them from the cold, including winter burn.

Winter burn can happen when a tree gets lots of sun and releases water during photosynthesis but then cannot replace that lost water because the ground is frozen. It shows up as patches of brown, dry and brittle needles on evergreens. Young trees are vulnerable to this, but it can be prevented by wrapping them. Wrapping can also help prevent sun scald, which damages the truck where the tree’s heartwood is exposed to the cold.

Wrap the trunks of trees with smooth bark, especially those that are young or freshly planted. If you have evergreens and shrubs that are manageable in size, wrap the entire plant in to protect the needles from ice, wind, heavy snow, and sun.

If wrapping the tree or shrub itself isn’t possible, you can build a screen around your plant to shield it from the winter winds. Check out your local greenhouse or garden centre. They have products available that make it easier to wrap or screen your trees and shrubs.

Winterizing native trees in Alberta

Various flowers and plants need different care, and so do different tree species! Deciduous trees have different needs than evergreens; young trees are more vulnerable to winter than mature ones, and delicate shrubs need more care than heartier ones.

Depending on the specific plants, trees, and shrubs in your yard, you might follow all or some of the steps we provided above. Below are a few examples of how to winterize trees and shrubs commonly found in Alberta.

Dwarf Alberta Spruce

Dwarf Alberta Spruce is petite with vibrant needles. It’s a beautiful tree, but it is a relatively delicate evergreen that needs protection in the winter.

Make sure you plant your Dwarf Alberta Spruce somewhere it is protected. Then, cut away any dead or ground-touching branches. Give it a deep watering and wrap it entirely to save its needles from winter burn and winds.

White Birch

White Birch is an iconic tree in Alberta, and we love its beautiful, thin, white bark and lush leaves. However, birch trees thrive in forests and can struggle in yards, so they need a little love.

Young birch trees are susceptible to sun scald, so wrap the trucks of newly planted birch for their first five winters or so. Mature birch trees are much heartier, and their reflective white trucks should stand up to sun scald.

Water your birch tree’s trunk and roots, then spread a good layer of mulch around the area to insulate it from the cold. Make sure the mulch isn’t touching the trunk! If the winter is particularly dry and cold, you may need to water your birch periodically throughout the season.

Honeysuckle Bush

Honeysuckle bushes are a favourite in Alberta, and the smell of their blossoms is incredible! It would be a shame to lose your shrub to our harsh winters.

To protect your honeysuckle bush, prune away dead branches and fertilize the soil. Then, spread an insulating layer of mulch over the root bed. Lightly wrap your shrub in burlap or a shrub cover from the garden centre.

Trees and shrubs beautify our properties, improve our home’s energy efficiency and clean the air. Let’s keep them protected and thriving this winter season.