A lush and vibrant garden starts with your garden shears. Pruning will benefit many of your favourite trees, shrubs and perennials. Pruning can help your plants develop more flowers, grow stronger, and healthier. Timing is everything when it comes to pruning, and with our guide, you’ll be off to a great growing season.
Generally speaking, prune any stems on the plant that are damaged, dead, or diseased as soon as you see them. Remove suckers (roots that shoot up to near or below the soil near the plant) and side branches.
Early spring, after frost; remove any dead or weak growth. Climbing roses and old garden roses should be pruned after they finish blooming. Hybrid teas, shrub roses, floribundas, grandifloras should be pruned in early spring to maintain shape and remove winter damage. Snipping off spent flowers during the growing season will promote new blooms.
Bigleaf hydrangeas (Hydrangea macrophylla) require little pruning. They should be trimmed back slightly after flowering. Avoid pruning in winter or spring because it will remove the flower buds.
Smooth hydrangeas (Hydrangea arborescens) should be pruned back in later winter or early spring as this encourages new growth and flowers.
Panicle hydrangeas (Hydrangea paniculata) bloom on new wood and should be pruned in late winter or early spring. Doing so will help create a fuller, healthier plant that is less likely to flop under the weight of its summer flowers.
Oakleaf and climbing hydrangeas generally don’t need pruning, but if you decide to follow the tips for bigleaf hydrangeas.
Spring Flowering Shrubs
Shrubs such as forsythia, flowering almond, purpleleaf sandcherry, lilacs and rhododendrons should be pruned after flowering in the spring. If you prune spring-flowering shrubs too late in the growing season, or winter you risk removing flowering buds.
Even if pruning for size is not required, remove the spent flowers; this will help the plant produce more flowers next year.
If you have any warm-season grasses (these turn brown as the weather turns colder) you can trim back in either fall or spring. If you have cool-season grasses (hold colour or deepen colour as cool weather arrives) you should prune in early spring. Dividing grasses is also a great idea.
Most flowering vines such as clematis (always double-check the variety as some flower on old wood), honeysuckle, and Boston Ivy are incredibly vigorous growers. These plants can be pruned in early spring.
Evergreens and Conifers
Lush evergreens, pyramidal cedars and junipers can be lightly pruned in early spring to remove any winter damage. Spreading evergreens can be sheared or thinned by removing individual branches. To have the pruning unseen, make the cut under an overhanging branch.
Coniferous plants such as spruce and fir, can have new growth removed by about half in June if necessary. Pruning can create a denser foliage canopy and new buds will be set at the cut. If you ever notice disproportionally tall growth at the top of these plants, it’s known as the “leader” and can be cut at this time. Do not cut below the lowest bud, or the leader will die back, damaging the tree.