Preparing Your Trees for Calgary’s Winters
Calgary winters can be tough on even the healthiest trees. With heavy snow, freeze-thaw cycles, and powerful chinook winds, trees face months of stress before spring returns. Without proper preparation, branches may break, bark may crack, and entire trees can decline over time.
Fortunately, proactive winter care can make all the difference. By taking steps to protect your trees in fall, you can help them survive Calgary’s harsh conditions and emerge in spring stronger and healthier.
Why Winter is Hard on Calgary Trees
Several unique challenges make Calgary’s winters especially tough for trees:
Heavy Snow Loads – Wet snow and ice accumulate on branches, causing them to bend or snap.
Freeze-Thaw Cycles – Chinooks bring sudden warmups, followed by deep freezes, stressing bark and roots.
Sunscald and Frost Cracks – Thin-barked trees like maples are prone to splitting when daytime heat contrasts with freezing nights.
Dry Winds – Evergreens continue to lose moisture through their needles in winter, leading to “winter burn” if roots can’t absorb water from frozen soil.
With these risks in mind, preparing trees before winter is essential.
Protecting Young and Newly Planted Trees
Young trees are especially vulnerable in their first few winters. Their thin bark, shallow roots, and limited energy reserves make them less resilient. Key steps include:
Trunk Wrapping – Use tree guards or breathable wraps to prevent sunscald and frost cracks. Remove wraps in spring to avoid pests.
Mulching – Apply a 2–4 inch layer of mulch around the base, keeping it several inches away from the trunk. Mulch insulates soil, retains moisture, and protects roots from extreme temperature swings.
Staking (if necessary) – Proper staking can stabilize newly planted trees during strong chinook winds, but stakes should be removed after the first growing season to encourage natural root strength.
These measures create a buffer that helps young trees establish strong roots and healthy growth.
Pruning Before Winter
Pruning weak, diseased, or dead branches before winter helps prevent storm damage. Snow and ice can weigh down branches, making them more likely to break and cause property damage.
Benefits of pre-winter pruning:
Reduces the risk of falling limbs near homes, sidewalks, and driveways.
Improves airflow and branch structure, making trees more resilient.
Helps arborists spot hidden defects that could worsen during winter storms.
For large trees, pruning should always be handled by an ISA Certified Arborist to avoid unsafe ladder work and improper cuts that can harm tree health.
Assessing Structural Weaknesses
Not all risks are obvious. A tree may look healthy but still be prone to failure under snow or wind loads. A TRAQ-qualified arborist (Tree Risk Assessment Qualification) can identify:
Weak branch unions.
Cracks in trunks or major limbs.
Root instability.
Trees leaning toward structures or power lines.
If needed, arborists may recommend cabling or bracing to provide extra support, helping trees withstand winter storms without breaking.
Watering Before the Ground Freezes
One of the most overlooked aspects of winter tree care is late-season watering. Trees that enter winter well-hydrated are far better equipped to survive cold months.
When to Water – During fall dry spells, water deeply until the ground begins to freeze.
How to Water – Use a slow soak with a hose or soaker system, ensuring water penetrates into the root zone.
Why It Matters – Frozen soil prevents water uptake, so trees rely on stored moisture through winter.
This step is especially critical for evergreens, which continue to lose water year-round.
Protecting Evergreens from Winter Burn
Evergreens like spruce and pine add beauty to Calgary yards, but they are particularly vulnerable to winter burn caused by dry winds and frozen soil. Signs include brown, scorched needles that appear in late winter or early spring.
To prevent this:
Anti-Desiccant Sprays – Applied in late fall, these sprays reduce moisture loss through needles.
Burlap Screens – Setting up windbreaks around evergreens reduces exposure to chinook winds.
Proper Watering – Hydrating evergreens in late fall ensures they have reserves to draw from.
These measures help evergreens retain their needles and maintain their year-round beauty.
Why Hire a Certified Arborist for Winter Prep?
While homeowners can take basic steps, winter preparation is best handled with professional guidance. An ISA Certified Arborist provides:
Species-Specific Recommendations – Tailoring care to your trees’ needs and Calgary’s climate.
Safe Pruning – Ensuring branches are cut correctly to promote long-term health.
Structural Assessments – Identifying hidden risks with TRAQ methods.
Long-Term Planning – Recommending strategies to improve resilience year after year.
With professional input, you can avoid costly mistakes and keep your trees thriving through Calgary’s toughest seasons.
The Bottom Line: Preparation is Protection
Calgary’s winters may be harsh, but your trees don’t have to suffer. By preparing in fall—through wrapping, mulching, pruning, watering, and professional assessments—you give your trees the best chance to survive the season and leaf out strong in spring.
Hiring an ISA Certified Arborist ensures your trees get the care they need—protecting your investment, your property, and Calgary’s urban forest.
