As we get closer to spring, the best times for pruning many deciduous trees and shrubs is slipping away. However, there is still plenty of time to do any necessary pruning. Some trees bleed heavily when pruning is done closer to the growth time. A few of these are maple and birch.
Pruning is easiest and cuts heal most rapidly if proper tools are used. Without proper tools, pruning can become a difficult chore and may be damaging to the tools and the plant. The main pruning mistake made is trying to cut a branch that is too large for the tool being used.
Three types of pruning tools are basic, and should be part of every home gardener’s equipment. Hand shears have many uses and are needed for easy removal of small twigs, old seed heads, or cutting branches up to about 3/4 inch in diameter. Shears are used not only for spring pruning, but also throughout the gardening season when plant shaping, flower cutting or a range of other gardening activities need to be done. Well-made tools may be expensive, but choose what suits your needs and is of good quality. If used properly, they should last many years.
For pruning branches from 3/4 to about 1 1/4 inches in diameter, lopping shears are very useful. Loppers have long, strong handles that help get good leverage for cutting off branches of trees and shrubs. The tool also may be damaged and blades bent by trying to cut branches too thick. Trying to cut thicker branches is tempting, but should not be done.
Where branches are more than 1-1/4 inches in diameter, a pruning saw should be used. There are different types, but one of the most useful and handy has a curved blade with fairly coarse teeth that cuts on the pull stroke. Some saws fold so the blade is covered when folded and can be placed in a pocket or holder for safer carrying while working.
For larger trees and limited pruning by homeowners, a pole pruner is helpful. The tool is usually a combination of both a curved pruning saw and a pruning shear attached to a long pole. The pole may be extended to reach 12 to 18 feet without a ladder.
Another common pruning tool is the hedge shears. These should only be used as their name implies and are designed to cut multiples of fairly thin shoots of current growth. Forcing shears to cut larger twigs will not only dull them, but may bend them and make them less efficient. Used properly and only for the proper purpose, they are useful tools.
General pruning of trees and shrubs is a combination of techniques called thinning out and heading back.
Thinning out is done by removing some shoots and smaller branches back to their base where the cut is made at a larger branch or trunk. No prominent stub should remain. This allows more light into the center of the tree or shrub, improves air movement and guides the future shape and development of the plant.
Heading back is the process of reducing the size of a tree or shrub and should be combined with thinning out. Heading back is done by selecting twigs or branches that need to be shortened. They are cut back to healthy side buds, which then grow to form a new shoot. The cut back, when done around and over the plant, will reduce its size while allowing it to remain in a more natural form and not look sheared.
Rejuvenation is often used on plants such as forsythia and lilac that have become overgrown and utilizes both techniques. Larger portions of the plants are removed. The thinning out may actually mean removal of selected branches back to near ground level. When the technique is needed, removal should be more gradual, probably over a two- to three-year period. One-third to one-half of the oldest branches are cut back severely each year. The remaining branches may be headed back.
If abundant new shoots develop after severe pruning, they also need to be thinned out by midsummer.
Clark Beusse is the Dawson County extension agent. For more information, call (706) 265-2442.