What Is Pruning?
Pruning involves the trimming or cutting away the branches or excess foliage of your plant. There are different ways to prune plants: pinching, heading, and thinning.
- Pinching is when you remove the main stem from your plant (literally by pinching with your fingers) to encourage new stems to grow, which helps promote a fuller plant while keeping it compact.
- Heading means to slice off portions of a plant’s branches, which help control plant size, stimulate the growth of side stems, and control the direction your shrubs or trees grow.
- Thinning prevents overcrowding by reducing the density of your foliage, allowing more sunlight to penetrate your garden, and limiting the areas where pests can hide.
When To Prune Your Plants
When you should prune your plants depends on which plants you’re growing. Pruning during the wrong time of year, like late in your plant’s growing season, may encourage new growth of buds that will die over the winter. For some plants, the extra foliage pre-pruning can serve as a protector throughout the winter.
For regular pruning maintenance, most annuals and perennials should be deadheaded all year round. Deadheading involves pinching off spent blooms and dead flowers so that the plant’s energy can be refocused towards sprouting new ones. For a general guide on when to prune your plants:
- Late winter: Trees should be pruned during their dormancy to prevent the spread of diseases. Warm-season beetles are attracted to open tree wounds and are busiest in the summer. Prune your trees during the winter when these pests are inactive to help prevent spreading illness to your trees. Some trees can also be pruned in the early spring.
- Early spring: Some gardeners prefer to prune their fruiting plants and trees in the early spring. Fruit trees are often pruned in the early spring, while the trees are still dormant and the young buds have not yet broken. Hedges (like beech and dogwood) and topiaries (like yew and boxwood) should also be pruned in the early spring, as it will dictate their growth throughout the season.
- Late spring: Prune most ornamental flowering shrubs and flowering plants (like forsythia or azaleas) right after their blossoms have fallen. Any sooner, and you could risk snipping growing flower buds. Perennial herbs like rosemary, sage, and oregano can become woody if not properly maintained, and should also be pruned in the late spring so their branches have time to harden off before winter.
- Early summer: Evergreen shrubs like Rhododendrons and Camellias need to be at their hardiest to properly survive the winter. These bushes should be pruned in the early summer (or late spring) to help them maintain their shape and remove any damaged bits to keep them in top condition.
- Fall: Gardenias, lavender, and certain hydrangeas thrive best when pruned in the fall as they’re going dormant, emerging with beautiful blossoms in the spring.
How to Prune Your Plants
How you prune and the types of pruning you do are just as important as the when. Your pruners and shears should be sharp and sterile. Cleaning your tools thoroughly after each use and before moving on to the next plant can help prevent the spread of pests or diseases. Where you prune your plant depends on the plant itself, but there are a few basics for certain vegetation:
- Evergreen shrubs: Shrub pruning sometimes follows the one-third rule, where pruning cuts only a third of the good wood, which is enough to stimulate regrowth without damaging the plant. When pruning shrubs, reach into the shrub with hand pruners and cut select branches. Remove any branches that sit on top of one another or stick out of form with the rest of the shrub. Dead or diseased branches can and should be removed at any time.
- Perennial flowers: To prune perennials, use small scissors to snip the main stem base of any old, dead, or dying flowers.
- Annual flowers: Annuals, like petunias and marigolds, can get leggy if not properly pruned. Leave the stems in the back of your plant, but remove the ones in front (about a third of the growth). Like a haircut, trimming the unruly ends will help thicken the growing plant, rather than letting it stay scraggly, all while your flowers in the back continue to grow.
- Fruit trees: Use a pruning saw or loppers to cut back the lead and side shoots of your fruiting plants like apple, cherry, plum, and pear trees. Avoid cutting into any woody growth where the fruit connects to the branch. You want to make room for air and sunlight to reach your budding fruits.
- Deciduous trees: If making heading cuts on young branches, cut at an angle sloping away from the bud, leaving no more than a quarter-inch stub by the terminal end of the stem. The angle should not be too steep, as that can cause the bud to dry out, and a completely horizontal cut may cause the bud to rot. Angle the slice in the direction you want your new shoot to grow.
- Seedlings: Thinning your seedlings is necessary for their proper growth and development in your vegetable garden. Identify which seedling foliage looks the strongest, and snip away the neighboring greens at soil level. This helps prevent overcrowding for crops like spinach, radishes, carrots, and beets.
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