Shrubs are surely the most versatile of landscape elements. With a little training or trimming, they can add a variety of shapes and textures to the yard (opposite).
Throughout the spring and summer, give shrubs a long, slow watering every 2 weeks—every 7 to 10 days during dry spells. Fertilize them no later than the spring growth spurt; later applications stimulate new growth that will suffer in winter.
Spread shredded pine bark or other organic mulch around shrubs to insulate the roots against heat and cold, and to inhibit weeds. Renew mulch in the spring and fall.
Few tasks are more important than pruning. It eliminates damaged and diseased wood as well as crossing branches, which can abrade each other and leave the plant open to infection. Pruning also encourages new growth and boosts flower and fruit production. Finally, pruning keeps the shrub in bounds and shapes it.
Prune shrubs several times a year. In the spring, remove winter damage and do light trimming. Wait to prune shrubs such as azaleas, which flower on old wood, until the blossoms have wilted. Most other shrubs can be pruned through the winter and up to midspring—or in summer after flowering.
Summer calls for biweekly shapings and trimmings. After the shrubs have flowered, snip off one third of the older stems at ground level, so that each plant renews itself every 3 years or so.
Some shrubs need protection from wind, cold, and snow. A local nursery can tell you which plants need help through the winter. Effective methods of protecting shrubs are shown on page 86. For the best results, winterize shrubs before the first hard freeze.
Heavy, wet snow is especially damaging to evergreens. After a storm, dislodge snow gently, taking care not to snap the branches.
Using shrubs in a landscape
Depending on where they are planted and how they are combined, shrubs offer many landscaping options. Besides their visual appeal, shrubs can be living fences or screens for trash bins and compost heaps. In deciding what shrubs to plant and where, consider how they will look in relation to the house, as well as how they appear from indoors. Landscape architects call a single free-standing shrub selected for its color, shape, or seasonal blossoms a specimen. Several shrubs differing in sizes and colors, perhaps combined with a tree, are known as a group. Shrubs strategically located to contrast with or complement an architectural feature are called accents. A closely spaced row of a single species forms a hedge, useful to define property lines and preserve privacy. A combination of trees and shrubs becomes an informal border, offering diverse and contrasting colors and textures.
Pruning to promote growth
To encourage a new branch (dashed lines) in a sparse area of a shrub, grasp a branch just below a lateral bud—that is, a bud pointing outward from the side of the branch. Hold a pair of pruning shears at a 45-degree angle and sever the branch about ¼ inch above the bud, taking care not to damage it (inset).
Removing damaged wood
Cut back a broken or diseased branch to healthy wood, either at a point just beyond a lateral bud or flush with the nearest healthy stem (left). After cutting branches from a diseased shrub, clean blades of shears or saw with alcohol to avoid infecting other plants.
Thinning for health and light
After the growing season each year, trim and shape the shrub’s outer branches. Remove completely any branches that are weak or misshapen, or that cross other branches. Prune individual branches at a main stem, and main stems near the ground (left). Then, to let sunlight reach new buds and foliage next spring, cut away up to one third of the oldest stems.
The right way to prune roses
Every fall—after the last bloom but well before the first frost—cut away deadwood, small shoots, and crossing branches. Then cut back every main branch by a third of its length (above, left). In the spring, cut away any stems damaged by winter weather. Then prune all healthy branches back to the point where their stems are at least ⅜ inch thick (above, right). The spring pruning should leave a compact, bowl-shaped bush. During the growing season, regularly trim away all dead and damaged wood, as well as small branches.
For a formal hedge, stretch a level string taut between posts at the ends of the hedge as a cutting guide. To speed the work, use an electric or battery-operated hedge trimmer held at the height of the string. Draw the trimmer across the hedge top, taking care not to poke the tip of the tool into the hedge. Alternatively, use hedge shears as shown in the inset. If any long shoots are growing into a gap in the hedge, cut the shoots back with pruning shears to stimulate thick growth that will fill the hole. Shape an informal, relatively irregular hedge as you would a shrub, using pruning shears and trying to create a natural, feathery appearance; take special care to prune out any branches that have grown faster than the others. Trim both formal and informal hedges narrower at the top than at the bottom, to permit sunlight to reach the base of the hedge. After trimming a hedge, shake it to dislodge the clippings, then rake them away.
Stirring up the soil
Cultivating the soil around a shrub bed makes weeding easier and watering more effective. Use an action hoe (left) to loosen weeds and break up compacted soil. Push the hoe blade about 2 inches into the earth—shallower if it catches the roots of a shrub—and work it back and forth parallel to the surface. After weeding the bed, use the hoe again to smooth the soil before watering or applying mulch.
Getting water to the roots
The best way to water specimens and small groups is with a sprinkler extension (above, left). This wandlike device with a fine-spray nozzle allows you to direct water at the base of a shrub. For larger groups and hedges, surround the bed with a sprinkler hose (above, right). Water shrubs for at least 10 minutes or until the soil is thoroughly saturated. Puddles on the ground indicate overwatering, which can damage the roots; stop watering immediately.
Twice a year, rake away old mulch from around shrubs and replace it with fresh material. In spring, spread an even layer of dense material, such as woodchips or ground-up bark, about 2 inches thick. Use only aged mulch—new chips and bark leach valuable nitrogen from the soil—and keep it away from stems; moisture in the mulch could encourage fungus, insect infestation, and root rot. Before the first frost, insulate the bed with 3 inches of pine needles or oak leaves.
Protection from wind and snow
Before the first frost, cover low-growing shrubs with evergreen branches (above, left) or spread a double thickness of burlap over them and peg it to the ground. To shield taller shrubs that are exposed to the full force of the wind, build a shelter of stakes and burlap to the full height of the shrub (above, center). First, drive several stakes in a tight circle all around the plant, then staple the burlap to the stakes. Wind twine around evergreens to prevent heavy, wet snow from weighing down the branches and breaking them. Loop the twine around the bottom of the shrub, then wrap it tightly enough to hold the branches upright (above, right). At the top, tie the twine into another loop.
Shelter under an eave
A sloping shelter on a frame of 2-by-3s prevents snow that slides off a roof from damaging shrubs next to a house. Cut a pair of pointed 2-by-3 posts at least 2 feet longer than the height of the shrubs and drive them a foot or more into the ground next to the house. In front of the shrubs, drive posts 1 foot shorter than the posts erected next to the wall. Fasten 2-by-3 crossbars to each pair of posts, then nail a canopy of 1-by-4s on the crossbars as shown at right.