Pruning

Mar 29, 2012

by Margaret Inwood, Lanark County Master Gardeners

Pruning should be done when plants are in full leaf to prevent excessive sap loss. Pruning is done to keep trees, shrubs and plants a good height and width, to remove dead and diseased branches and to encourage flowering and fruit development. Sometimes pruning is used to shape plants to an unnatural form (topiary) and also to rejuvenate old flowering shrubs.

Pruning is known as a dwarfing process that keeps plants smaller than ones that are allowed to grow freely. Broken branches caused by storms can be pruned immediately. Trees and shrubs that bloom in the spring

or early summer should be pruned AFTER they bloom. Fruit trees are pruned in the late winter or very early spring before bud break. Late flowering shrubs produce flowers on the current season’s growth and are pruned in the spring before they start to grow.

To prune, use sharp saws, shears, loppers or secateurs to make clean cuts and allow wounds to heal fast. Ragged or torn tissue does not heal quickly. Pruning cuts should be made a quarter inch above an outward

growing branch or bud at a 45° angle. Do not leave stubs that will die. Remove broken and diseased ranches, particularly in the centre of the crown of the plant, then remove weak branches or shorten their length if removing them will spoil their natural form.

When older shrubs become overgrown, flowering is reduced and pruning is needed to improve blooming. Shrubs such as spireas, which have become twiggy and ratty looking, can be cut right down to the ground

in the fall. In the spring, they will grow anew from the base and by mid June will look lush and brand new. Most shrubs can be maintained by removing one third of the oldest wood yearly until the shrub is composed

of no more than four-year-old wood. When pruning trees, do not remove the leader.

All your gardening questions can be submitted and answered at www.lanarkmastergardeners.mgoi.ca