Many shrubs grow rapidly, and become overgrown, excessively twiggy, and weighted down with excess foliage.
This bushiness eventually obscures the structure of shrubs, reduces flowering, and invites fungal disease. Periodic pruning makes them more attractive and healthier. Pruning to control size is a waste of time -- they will just grow back. Instead, guide them so they grow to their mature size with strong stems and healthy foliage.
Experienced gardeners usually do their major structural pruning when shrubs are dormant, then perform follow-up shaping during the growing season, after the spring growth spurt. Prune your flowering shrubs to shape them after they've bloomed and before they set buds for the following year, so you don't inadvertently remove the buds and ruin next year's bloom. Plan to shape spring bloomers, such as rhododendron, azalea, and forsythia, in early to mid-summer. Wait to shape summer bloomers, such as crape myrtle and glossy abelia, until autumn.
Clip branches individually, and reserve shearing for hedges. The idea is to groom the shrub to curb unruliness, not to change its appearance. Properly shaped, the shrub should look essentially the same, only neater.
Whether deciduous or evergreen, trees and shrubs have a dormant period. Except for certain tropical trees, this rest time is usually during the cold winter months. During the period when days are short and the ground is cold, they suspend active growth and live off stored energy. Warm weather triggers new vitality.
When shaping shrubs, achieve optimum results by honoring their natural habit. Use restraint. Respect the fact that each shrub is genetically programmed for a certain size, profile, and branching pattern. Make cuts that support these features and preserve the essential character of the plant. Lollipop shapes look unattractive on the front lawn. Leave the highly stylized pruning -- topiary, pollarding, and bonsai -- to the experts.
Overgrown shrubs look unkempt and unattractive and don't bloom well. Thinning the dense foliage-covered branches of this forsythia allows light and air to penetrate and improve its health.
1. The first step is to cut back excessively long branches. Clip them off where a leaf emerges back on the stem near the main mass of foliage. Avoid making them all identical lengths.
2. Reach deep within the dense tangle of branches, clip off particularly large or twiggy ones to the point where they join a main branch.
3. Once its general shape is established, give the shrub a final once-over. Be sure no branches rub against walls or tangle in nearby plants.
1. If the foliage on the sides of the hedge gets insufficient sunlight, it will die back. Taper the sides of the hedge so that the lower branches are wider than those at the top.
2. To stimulate growth, trim a hedge with hedge shears or electric clippers below the desired height in spring. When you prune later in the season, don't remove all new growth.
1. Boxwood shrubs are commonly used as hedges because they tolerate repeated shearing well. However, when planted individually, they contribute attractive, fine-textured evergreen foliage. Periodically clip them to neaten their appearance.
2. Use hand pruners, rather than the hedge shears, to clip off individual branches that protrude from the main foliage body of the shrub. Cut the branches at slightly different lengths to avoid creating a round profile.