Spring Gardening Checklist

Brush Up on Pruning

Pruning can be one of the more artistic activities in the garden, but many people find it daunting and aren't sure where to begin. While a sense of apprehension can be good if it prevents unnecessary damage (everyone seems to have a story about a hapless gardener who removed all of a season's fruit or flower buds) it shouldn't hold you back entirely from this essential and rewarding task.

Why Prune:

Pruning promotes plant health, stimulates fruit and flower production, and improves the overall aesthetics of your garden. Removing dead or damaged limbs reduces a plant’s susceptibility to pests and disease. Pruning can mean the difference between a landscape that feels overgrown and busy and one that is balanced and calm.

Before You Begin

Sharpen and disinfect your tools. Then, think about what you want the plant to do in the future. You might need to familiarize yourself with the mature growth habit of the tree or shrub, its growth rate, when it flowers, whether it flowers on old or new wood, and when it should be pruned. It's also good to consider whether the plant has any known irritants to your skin or respiratory system. Notable plants in this category are agave, fremontodendron, and euphorbia. Many people develop rashes from contact with pine and spruce, as well. When you're ready to start cutting, the first step is to remove dead, diseased, or crossing limbs. This can be done at any time of the year. After that, have a look at the overall shape and balance of the plant. Determine if it has twisted, weak, or rubbing limbs that may need to be removed. Also, remove limbs growing downward or touching the ground. Then, prune to reduce crowding, renew growth and create a balanced shape.

Fruit Trees:

Remember that sunshine is needed to ripen fruit so aim to have evenly spaced lateral branches and open centres. On young fruit trees, cut back whips by 1/3, choose a strong leader and cut back competing ones. On established trees, prune to retain the framework. Cut back suckers, water sprouts, branch stubs and narrow crotch angles. Ideally, the framework branches should spiral around the tree in an alternate arrangement instead of being opposite one another on the trunk. Prune leaf shoots back to three buds to encourage the tree to produce fruiting spurs. Prune to an outward-facing bud and angle the cut away from the bud.

Roses:

Prune roses in early spring, after the threat of frost. Remove canes growing toward the centre, as well as anything dead, diseased, or crossing. Don't be afraid to prune roses back hard, reducing the height to roughly 1/3 or a little more.

Wisteria:

Prune in late winter by cutting side shoots back to three or four outward-facing buds. Prune again during the growing season to control vegetative growth and stimulate the production of flowering spurs.

Hydrangeas:

On established hydrangeas, cut up to 1/3 of the old canes to the ground in order to rejuvenate the plant. Hydrangeas tend to flower more profusely on younger growth and the old wood crowds the centre, limiting airflow. Deadhead hydrangeas that bloom on old wood (lacecap, big leaf, mop head, and oakleaf) after they finish flowering by cutting back to a strong set of buds. Hydrangeas that bloom on new wood (paniculata and arborescens) can be cut back by 1/3 in the dormant season. Standard hydrangeas should be pruned hard to prevent splitting.

Evergreens:

Reduce candles by 1/3 once their flush of new growth is finished and before the buds break.

Root Pruning:

Do this only if a tree or shrub planted in a pot has become rootbound, or if you want to arrest the plant's growth. This can also be a last resort for a tree or shrub that is getting too big for the area it's planted in if it can't be transplanted elsewhere.

Don't Prune:

At the wrong time of year. Forsythia, magnolia, and flowering dogwood in winter, for instance (unless doing a renovation prune). Also, be careful not to remove spent blooms that produce attractive berries, particularly those that are food for birds. For instance, callicarpa, many viburnum species, elderberry, and pyracantha. Avoid pruning in midday sun (particularly on boxwood) as some newly-exposed growth can be scorched.

Before You Call it a Day

Spray fruit trees and roses with dormant oil and lime sulfur, but do so before the buds break. Clean up any debris to prevent the spread of disease. This is particularly important with boxwood, which is susceptible to blight.