Tree Fertilizing in Fall: Give you Trees a Healthy Head Start for Spring

As temperatures drop and trees begin to wind down for the season, many Calgary homeowners wonder: Is fall a good time to fertilize my trees? The answer, when done correctly, is yes, fall fertilization can give your trees a healthy head start for spring. But it’s not as simple as scattering fertilizer and hoping for the best. Timing, soil conditions, and proper formulation all matter.

At Evergreen LTD, our ISA-certified arborists help Calgary residents make the right fertilization decisions for healthier, stronger trees year-round. Here’s what you should know, and when to call in the pros.

Why Fertilize Trees in Fall?

Fall fertilization supports the natural rhythm of your tree’s growth cycle. While trees may look dormant above ground, their roots are still active as long as the soil hasn’t frozen. That means they can absorb and store nutrients through winter, ready to use when spring growth kicks in.

Benefits of fall tree fertilization in Calgary include:

• Recovery from summer drought and heat stress

• Stronger root development before winter

• Improved spring leaf-out and shoot growth

• Boosted resilience and health going into the new season

• Potentially improved cold tolerance (depending on species and rates)

Want expert guidance on timing and nutrients? Contact Evergreen LTD today to schedule your fall tree consultation.

When Should You Fertilize in Fall?

Timing is everything. Fertilizing too early can encourage late-season shoot growth that’s vulnerable to frost. Fertilizing too late, after the ground freezes, means roots can’t take up the nutrients.

Our recommended timing for Calgary:

• Wait until after leaf drop or about one month after the first killing frost

• Ensure soil is moist, but not saturated

• Avoid fertilizing during warm spells in early fall

• Complete fertilization before the ground freezes

What Kind of Fertilizer Should You Use?

Choosing the right fertilizer means aligning with your tree’s needs and Calgary’s soil conditions. Nitrogen is key for overall growth, but phosphorus and potassium also play important roles in root development and stress resistance.

We recommend:

• A balanced, slow-release formula (e.g. 4:1:2 N:P:K)

• Moderate nitrogen rates (no more than 3 lbs per 1,000 sq. ft.)

• Avoiding quick-release or high-nitrogen blends, which can damage roots or reduce cold hardiness

Not sure what your trees need? Evergreen LTD offers soil and tissue testing to create a customized nutrient plan.

How to Apply Fertilizer Safely and Effectively

Improper application can do more harm than good. Too much fertilizer or the wrong placement can lead to nutrient leaching, root burn, or wasted product.

Best practices include:

• Broadcasting granular fertilizer across the root zone (from mid-crown to beyond the drip line)

• Avoiding application near the trunk—nutrients won’t be absorbed there

• Considering soil injection methods for deep root access (ideal for urban trees or compacted soils)

• Avoiding fertilizer spikes unless soil moisture and root distribution are well understood

Common Mistakes to Avoid

Even well-meaning homeowners can cause long-term harm to their trees by fertilizing at the wrong time or with the wrong products.

Watch out for:

• Fertilizing in August or early fall while the tree is still active

• Overapplying nitrogen in hopes of “supercharging” growth

• Using fertilizer to treat unknown issues, always test soil first

• Ignoring signs of leaching or runoff in wet winter conditions

Want peace of mind? Our ISA-certified arborists ensure your trees get exactly what they need, no more, no less.

Is Fall Fertilization Right for Every Tree?

Not always. Some tree species, such as red maple or crape myrtle, may show reduced cold hardiness when over-fertilized in fall. Sandy or sloped soils in some Calgary areas are also more prone to nutrient leaching.

This is why Evergreen LTD evaluates each property, tree species, and soil condition before making fertilization recommendations.

Why Choose Evergreen LTD?

DIY tree care can be risky, especially with something as sensitive as fertilization. Misjudging timing, dosage, or soil conditions can lead to weak spring growth, winter damage, or wasted effort.

With Evergreen LTD, you get:

• ISA-certified arborists with expertise in Calgary’s urban forest

• Science-based, species-specific fertilization strategies

• Soil testing and analysis before application

• Safe, precise application with professional-grade equipment

• Ongoing support and tree health monitoring

Give your trees a strong start for next spring, without the guesswork. Contact Evergreen LTD now to book your fall fertilization service.

Set Your Trees Up for Success This Spring

Fall fertilization, when done correctly, is one of the most effective ways to strengthen trees ahead of Calgary’s harsh winter and unpredictable spring weather. By supplying nutrients during dormancy, trees build root reserves and improve spring performance.

But proper timing, formulation, and application are crucial. Don't risk your landscape with guesswork or one-size-fits-all solutions. Let Evergreen LTD guide you with professional, tailored tree care backed by ISA-certified expertise.

Schedule your fall tree fertilization with Evergreen LTD today Protect your investment. Enhance your landscape. Trust the experts.