It's Spring; What Can I Prune?
Confused about when and what to prune in the Spring? Spring has its own set of rules and reasons for pruning.
Spring is an awesome time for gardeners. You can focus your attention on lots of different tasks, each day bringing a completely different set of challenges and each task completed a new sense of accomplishment.
Pruning is one of those tasks that can be a bit confusing, though. Pruning a plant in the wrong season can cause undue setbacks, but when done in the proper season pruning is extremely helpful. For healthy, tidy plants with great-looking blooms it's important to prune the right thing at the right time.
Spring bloomers, like forsythia, quince, lilac and azalea, should be pruned soon after they finish blooming. These shrubs bloom on "old" wood. Pruning early in the season allows the longest amount of time for them to grow next year's buds. Use prudent judgement, however; these plants may not need pruning at all if they are in a good spot and healthy. They often look their best when they grow as naturally as possible. There is no need to prune just because you have time on your hands.
Some flowering shrubs produce multiple bloom cycles per year. Each year, new brands of roses, azaleas, hydrangeas and more appear in garden centers presenting the question: When should they be pruned? Many of these bloom on both old and new wood, with the first round of flowers appearing mid-spring. In spring, treat these shrubs as you would the spring bloomers by pruning as soon as the first bloom cycle is complete. If the plants are still well shaped and suitably sized, limit pruning to the removal of spent blooms.
When hedges such as boxwood, holly, ligustrum, podocarpus and others which are grown for foliage rather than flowers, put on their first flush of new growth they may look a bit shaggy. For a tightly groomed appearance, shear them. Cut the young foliage only, about half the distance back toward the old growth (for instance, a flush of four inches should be cut to two inches). Pruning in this manner allows the plant to grow slightly larger, which helps the canopy stay deep and full. It will also help to minimize production of long shoots.
Old shrubs that have grown too large for their space, or have seen extensive damage from cold, disease or insects, may require renewal pruning. Simply put, they are cut to the ground and allowed to regrow from root suckers. This drastic measure is often used to get a few more years out of shrubs that will in the future have to be replaced. Spring is the time to do this, at the time when the first buds begin to swell at the branch tips but before the new growth starts to emerge.
As the suckers grow back, pinch the tips to force these aggressive shoots to produce lateral branches for a bushier plant.
Pruning trees in early spring, prior to full leaf flush, is the accepted practice. Because of the impending season of rapid growth, pruning wounds heal quickly to exclude insect and disease infestation. A few notable exceptions include birch, maple and walnut. These trees have heavy sap flows during early spring and should not be pruned until they have fully leafed out and hardened off. Dead branches may be removed at any time of year.
Needle leafed trees may be pruned in spring. Take care to take one of two approaches for best results. Either shear only the green tips as they produce new growth; or if it is necessary to cut woody branches, make the cuts far enough back so that the remaining foliage hides the cut branches.
Spring flowering bulbs may be pruned back to the ground once the leaves turn brown later in spring, or early summer. It is important to leave the foliage in place for the post-flowering period so that the leaves can feed and recharge the bulb with energy for a great bloom show next spring.
Basic tools for pruning these categories of plants include hand held pruners, loppers, shears and pruning saw. Hand held pruners work well for fine stems and branches up to æ inch in diameter. Loppers are used for branches between 1/2 inch and 2 inches. A saw is necessary for larger branches. Shears are used to keep hedges and topiaries well groomed by cutting through soft green growing tips.
Keep tools sharp and clean. Sharp tools make clean cuts which heal far more quickly than those with ragged edges. Use a diamond hone frequently on pruners, loppers and shears. Clean tools minimize the spread of fungal and viral diseases from plant to plant. It is good practice to clean pruning blades with Lysol, Listerine, or plain old rubbing alcohol when moving from one plant to the next. Use turpentine or mineral spirits to remove sap buildup. Stay away from chlorine as it can corrode the metal. Oil the blades periodically during the season and prior to storage.
With a a little maintenance and a fresh "haircut", your plants will be set to go this spring. They will reward you for your diligent work with beautiful foliage and bloom all summer long!