Pruning Guide
General Pruning Tips
Basic Objectives of Pruning
- Maintain plant health and vigor
- Influence plant size and shape
- Influence bloom and fruit production
Basic Pruning Rules:
- Protect yourself by using the proper safety equipment for the job (see following page)
- Use the correct pruning tools for the job. Make sure they are sharp and clean.
- Prune just outside the branch collar (wrinkled area between trunk and branch)
- Prune small stems just above a leaf or branch joint or node
- Remove damaged, dead or diseased wood as soon as it is noticed.
- Disinfect pruning tools between cuts when pruning diseased plants. Dip tools or spray on a 10% bleach solution.
- Remove crossing branches before they enlarge and start rubbing together.
- Protect large pruning wounds from external disease by applying a paste made from water and a sulphur product. (lime sulphur, copper sulphate)
Hedges
Newly planted hedges such as cotoneaster, caragana, and lilac, should be pruned back to encourage lateral branching which creates a fuller hedge more rapidly. As your hedge develops, trim it so that the base is wider than the top. This allows sufficient sunlight to reach all leaf surfaces, preventing the base of the hedge from becoming open and sparse. Hedge shearing can be carried out at any time during the growing season. Older hedges in need of rejuvenation are more easily thinned out during the dormant season, from November til March.
Shrubs
Shrubs that flower on old wood in the spring such as forsythia, double flowering plum, Nanking cherry, or lilac, for example, should be pruned as soon as flowering is finished. Pruning at any other time of the year will remove the dormant flower buds. Flower buds for most shrubs are formed on previous year's growth. White spireas such as Bridal Wreath, Garland, and Three-lobed also flower on old wood. Any other shrub that flowers in summer on old wood should be pruned immediately after flowering; ie. mockorange. To prune older shrubs, usually requiring thinning, occasionally remove entire large branches by cutting them out at the base.
Shrubs That Flower on New Wood:
Many shrubs bloom on new wood, such as elders, hydrangea, dwarf pink spireas (S. bumalda and S. japonica cultivars), and most hardy roses and hybrid tea roses. In spring, remove dead and weak stem and thin out about 1/3 of the old stems down to ground level. The remaining stems can be trimmed back if desired. Hybrid teas may be pruned the same way but in late fall they are usually cut back to about 8 in.(20cm) so they can be more easily covered for winter. For grafted Roses, suckers which emerge from below the graft are removed during the summer, as they originate from the root stock.
Shade Trees
Shade trees should be trained when they are still young. By shaping shade trees early, unwanted lower branches, crossing or rubbing branches, and branches growing in the wrong location or direction are eliminated. Most shade or ornamental trees prefer to be pruned during the dormant season - Nov. til March. However, birch and maple (which are called "bleeders"), should be pruned in mid-summer, usually in July or August. This is because pruning cuts on birch and maple heal better if pruned after their leaves are fully expanded. Most shade trees, if properly located and pruned when young, will require less pruning when mature. If you do have large trees requiring pruning, we recommend you consult a professional pruning service or a certified arborist.
Fruit Trees
Fruit trees such as apple, plum, or pear, are pruned during the dormant season in late winter to encourage vigorous growth and to create a better producing tree. Prune fruit trees so that all parts of the tree receive adequate sunlight. Unwanted lower branches, crossing or rubbing branches, and branches growing in the wrong direction or location should be removed when the tree is young. Any suckers growing from the roots or water sprouts growing from the trunk should also be removed. To prevent fruit from overloading limbs, thin the smaller, outside branches during the dormant season. To increase fruit size, thin fruit to 2-3 apples/cluster in early summer.
The new growth on pines, called "candles", should be cut in half in June, to encourage a compact shape. Cedars and junipers may be shaped at any time. The long soft, new growth on spruce may be shortened to shape it, or minimize growth, in June. If the leader of a spruce is damaged or removed, a new one may be formed by tying a sturdy stick to the trunk, extending it above the top of the tree, and bending and tying one top branch up to the stick. You can avoid having to keep evergreens smaller than their natural size by choosing varieties that have an appropriate mature size.
