ecoscapes blog

Jumpstart Your Garden with Late Winter Pruning

Ah, late winter. Is there anything more glorious than seeing bare branches of deciduous trees and shrubs?

Okay, that’s a grim scene, I admit. Yet the fact that shrubs and trees are leaf-free makes this a great time of year to prune many species1 to improve their shape and health.

Before leafing out, you can get a good idea of a plant’s overall structure. Their natural shape may be ‘out of whack,’ for example, as branches receiving more sunlight grow faster, creating an unbalance. And with many multi-stem shrubs and trees, branches tend to crowd each other over time. Without adequate air circulation, fungal diseases can take hold. Branch overcrowding also prevents sunlight from penetrating to inside branches, stressing the plant’s growth.

Not all trees and shrubs, however, are good candidates for early winter pruning.

Avoid pruning birch, elm and maple trees in early winter because these species have sap that will bleed after pruning. The sap contains minerals and nutrients that flow through branches to energize new bud formation. These trees should be pruned in the coldest part of winter. Also, it is better to prune oaks mid-winter to help prevent the spread of a fungal disease called oak wilt. It is also better to hold off vigorously pruning spring flowering shrubs as this will mean a less floriferous display once spring arrives.

The right tools for the job

Before making your first cut, you need to have the proper tools on hand. The right tool depends on the branch diameter:

• Bypass hand pruners—branches under 1 inch diameter.

• Bypass loppers—up to 2 inches in diameter.

• Bypass pole pruner—for branches out of reach. Typically up to 2 inches in diameter.

• Pruning saw—available as a hand or pole saw. For branches up to 4 inches in diameter.

Bypass pruning tools are ones where the blades move past each other, like scissors. This helps ensure cleaner cuts. Here are tips on how to properly sharpen hand pruners and loppers.

Pruning step by step

The first task of pruning is to remove dead and diseased branches. If you’re unsure a branch is dead, scratch its bark. It’s alive if you find green tissue underneath.

Next, remove branches that rub against one another; this can create wounds for insects and diseases to enter. Cut back branches that are growing towards the inside of the plant to ensure good air circulation and ample light. If a branch creates a ‘V’ shape with one part growing directly beneath another, remove the less robust one.

On trees, you’ll want to remove ‘water spouts,’ branches that grow straight out the top along a branch’s length or scraggily growth on the trunk where branches were previously. And prune back ‘suckers,’ the stems that grow up around the base of some trees.

When removing larger branches growing out of a single stem tree, first make a cut on the bottom of the branch about three inches in front of the branch collar. The collar is the swollen portion where the branch meets the tree. This lower cut will prevent the bark on the trunk from being damaged when you make your final cut. The final cut should be just beyond the collar; never make a cut flush with the trunk. Done correctly, the tree will heal this wound itself.

If you are pruning back a branch instead of removing it, cut the branch at a 45-degree angle to just above the next live bud on the branch. The short stem above the bud will die off.

Tips for tip-top results

As you prune, periodically stop and view the plant from different angles. This will help ensure that you create the shape you desire. To ensure a plant can recover and flourish from pruning, do not remove more than 1/3 of its branches.

If you suspect some parts of your plant are diseased, clean your pruning tool’s cutting edges between cuts with a cloth soaked in a mixture of 10% bleach solution and water or undiluted 70% isopropyl alcohol. This is a smart idea when moving from one plant to another.

Sometimes multi-stem shrubs become so overgrown, misshapen or are dying out in the center that they require ‘rejuvenation pruning.’ This involves cutting back all a shrub’s branches six to 24 inches above the ground. To help the plant recover, spread quality organic compost around its base and make sure it’s well watered. Rejuvenation pruning should only be done every three to five years.

With patience and practice, you’ll be a pruning pro in no time! When your pruned shrubs and trees leaf out, you can take satisfaction that you’ve made them more attractive and healthy.

Happy pruning!

1 This article is focused on smaller deciduous shrubs and trees. ‘Smaller’ means no more than 12-15 feet tall. In other words, ones you can prune with pole loppers or a ladder without endangering your safety.