Figuring out what is the best time of the year to prune your shrubs can be a difficult task for most homeowners in Canada. They are typically not sure of when new growth starts or if they should trim their shrubs during the harsh Canadian winter. In this article, we will tell you why the early spring or late winter is the best time to prune your plants. We will also touch on tips for proper pruning, as well as what you should not do while pruning to ensure that your garden looks great.
Choose Winter or Early Spring
When you prune a plant, you want to avoid cutting your plant during the growing season. This will make sure that no branches or new growth are damaged as the plants are cut back. In order to be safe, you should pick a time of year when the new growth has stopped like during the late winter and early spring. During this time of the year, plants are dormant, meaning they have stopped growing to preserve themselves and their nutrients for the cold season. This makes the late winter or the early spring the best time of year to prune your trees and shrubs.
Fall Is The Worst Time To Prune
Did you know that cutting back old branches and stems encourages new growth? This means that whenever you prune your trees or shrubs, you are giving them a head start for this year’s growing season. If you choose to remove old or diseased branches – even just to shape or form your plant – during the fall, you are encouraging new growth.
Instigating new growth in your plants during the fall can put the plant under a great amount of stress. The fall is when plants are preparing to go dormant, not start new growth.
Trees and Shrubs To Prune
Keep Chipped Hedges Looking Great
Shaped or clipped hedges like boxwood or privet should be either in the late winter and early spring or the mid-to-late summer. The top of the plant should also be kept narrower than the base so the sunlight reaches the old wood at the bottom of the shrub.
Remove Unwanted Evergreen Branches In The Winter
Evergreens are beautiful trees and shrubs that keep their lush green colour all year round. This can make it difficult for many gardeners to determine when they can cut a branch of their tree without damaging the wood or tree entirely.
It is best to remove dead or unwanted lower branches from evergreens during the late winter. Just like other plants, evergreens will go dormant during the winter. It is best to prune your evergreen during the winter because you can cut off a branch before growth begins, giving the tree an opportunity to heal.
Keep Flowering Plants Blooming
Trees and shrubs that produce flowers have different pruning times depending on what part of the branch their flowers bloom from.
Flower Buds on 'New' Wood
A tree or shrub that produces flowers or fruit on this year’s growth should be pruned in the late winter or early summer before the new growing season begins. When pruning is done at this time, overgrown fruit trees or flowering shrubs may produce more flower buds and fruit later in the spring.
If you like seeing your fall-blooming clematis, smooth hydrangeas, panicle hydrangeas, potentilla, roses, rose of sharon, dogwoods in bloom, take the time to prune in the early spring.
Flower Buds on 'Old' Wood
If your plant’s flower buds will bloom on growth that happened last summer, then it is an ‘old’ wood flowering tree or shrub. Some examples of these types of flowering plants are azalea, spring-blooming clematis, flowering almond, forsythia, and lilacs.
If you prune your tree or shrub too early into the spring, you risk cutting off buds and other blooms. This would severely hinder the year’s growth as the plant needs to try to collect more nutrients and energy to attempt its spring flowering again. Any flowering shrubs or trees like lilac, rhododendron, and forsythia should be pruned in after they bloom in the late spring or early summer to avoid pruning flower buds that are important for pollination.
Deciduous Shade Trees
It is much easier to prune deciduous trees during the winter or early spring because their foliage is gone. This can allow you to see the real form of your tree or shrub without needing to cut back as many branches. Just be aware that you may see an abundance of sap when pruning “heavy bleeders” trees like maples, dogwoods, and elms during the winter.
How To Prune Trees and Shrubs
Remove Dead Or Diseased Stems
The first place to start when pruning your trees and shrubs is to look at the stems of the plants. After a long winter and before any growth begins, you may notice that some stems or branches have been damaged by the cold season or other factors. Damaged or diseased stems should be pruned to avoid the damage or disease spreading to the entire plant.
Prune On A Mild Winter Day
Keep your pruning activities to mild days in the late winter and early spring. This will make pruning more enjoyable for you and it will reduce the chances of disease spreading. Many diseases that are waterborne will not spread through your garden as easily if it is too cold outside.
Remove Branches And Cuttings From The Ground
After you complete your winter pruning, take the time to pick up the cut or dead wood pieces from the ground surrounding the bottom of the plant. This will allow more air, light, and water to reach the base of the tree easier. As a result, your plant’s spring growth may be much more spectacular than the year before.
Cut At The Node
A plant’s node is where branches, leaves, and aerial roots grow out of a plant’s stem. This is the most effective spot to prune because it cuts back any dead or old wood at its main source. As you prune the old areas of the plant, growth is stimulated and new buds will appear.
You can easily find see a node when inspecting one of the main stems or branches of your plant. The wood will have a callus-like bump where flower buds or new stems grow from. Plants need to be pruned just above the wood node to maintain their ability to produce branches, stems, or flower buds from that stem.
Pruning Your Garden
Pruning your garden can be much more complicated than you are led to believe, but it is essential for maintaining the health and beauty of your garden. Before you start pruning, remember to:
We have tried to simplify pruning in this article, but it can be difficult to determine when you should or shouldn’t prune. Riverwood Landscape can provide any tips or services you may need to keep your southern Ontario garden looking great.