Why Prune in Spring?

Pruning in early spring—before buds break and sap starts flowing—is ideal for most deciduous trees and shrubs. This timing helps:

• Encourage strong new growth
• Improve air circulation and shape
• Prevent disease spread
• Remove any winter-damaged or dead wood
  
  

Important: Do Not Prune Elm Trees Between Apr. 1 and Sept. 30

Under Alberta’s Dutch Elm Disease (DED) Prevention Regulations, it is illegal to prune elm trees from April 1 to September 30. This is when elm bark beetles—the carriers of this deadly disease—are most active. Pruning during this time can attract the beetles and increase the risk of infection. To learn more, visit: https://www.alberta.ca/dutch-elm-disease.aspx

General Spring Pruning Guidelines

Here are a few tried-and-true techniques for successful spring pruning in Zone 3:

1. Know Your Plants

Different species require different approaches. For example:

• Lilacs and Forsythia should be pruned after they bloom, as they flower on old wood.
• Apple, cherry, and dogwood trees are great candidates for early spring pruning.

Guide from Alberta Agriculture & Forestry:
https://www.alberta.ca/pruning-trees-and-shrubs.aspx

2. Use the Right Tools

Sharp, clean tools make cleaner cuts and reduce the risk of disease. Essential tools include:

• Bypass pruners for small branches
• Loppers for medium branches
• Pruning saws for thick or hard-to-reach limbs

Tool care guide from Garden Fundamentals:
https://www.gardenfundamentals.com/pruning-tools-sharpening-cleaning/

3. Cut With Purpose

Focus on:

• Removing dead, diseased, or damaged wood
• Cutting back crossing or crowded branches
• Shaping to encourage balanced, open growth

Cutting techniques guide from University of Minnesota Extension:
https://extension.umn.edu/planting-and-growing-guides/pruning-trees-and-shrubs

4. Wait on the Evergreens

For conifers like spruce and pine, wait until late spring to early summer when new growth (“candles”) appears. Prune only the soft new tips to shape or reduce size.

Evergreen pruning tips from Gardening Know How:
https://www.gardeningknowhow.com/ornamental/shrubs/shgen/pruning-evergreens.htm

Bonus: Pruning for Wildlife Habitat

While pruning is important for plant health, be mindful of nesting birds and beneficial insects that may rely on your shrubs and trees. Avoid major pruning after mid-May when birds may be nesting.

Local Support & Resources

Need help identifying what to prune or when? Check out these helpful organizations in Alberta:

• Alberta Horticultural Association:
  https://www.albertahort.org/
• Calgary Horticultural Society:
  https://www.calhort.org/

Happy pruning, Trochu gardeners! With a little care and attention now, your plants will reward you all season long with vibrant growth and lasting beauty.