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Ch. 8, pp. 12 - 16

Hedges consist of plants set in a row so as to merge into a solid, linear mass. They have served gardeners for centuries as screens, fences, walls, and edgings.
Hedge Pruning
Hedge Pruning
A well-shaped hedge is no accident. It must be trained from the beginning. The establishment of a deciduous hedge begins with the selection of nursery stock. Choose young trees or shrubs 1 to 2 feet high, preferably multiple-stemmed. When planting, cut the plants back to 6 or 8 inches. This will induce low branching. Late in the first season or before bud-break in the next, prune off half of the new growth. In the following year, again trim off half the new growth to encourage branching.
In the third year, start shaping. Hedges are often shaped with flat tops and vertical sides. This unnatural shaping is seldom successful. The best shape, as far as the plant is concerned, is a natural form — rounded or slightly pointed top with sides slanting to a wide base. After plants have been pruned initially to induce low branching, the low branching will be maintained by trimming the top narrower than the bottom, so that sunlight can reach all of the leaves on the plant.
Snow accumulates on broad flat tops Straight lines require more frequent trimming


Peaked and rounded tops hinder snow accumulation Rounded forms, which follow nature's tendency, require less trimming

Rounded or peaked tops aid shedding snow, which if left, may break branches. Before shaping, some thought should be given to the shape of the untrimmed plant. For example, naturally conical arborvitae does particularly well in a Gothic arch shape. Common buckthorn, a spreading plant, is more easily shaped to a Roman arch.
Trim to the desired shape before the hedge grows to the desired size. Never allow the plants to grow untrimmed to the final height before shearing; by that time it will be too late to get maximum branching at the base. After the hedge has reached the dimensions desired, trim closely in order to keep it within bounds.
Evergreen nursery stock for hedging need not be as small as deciduous material, and should not be cut back when planted. Trim lightly after a year or two. Start shaping as the individual plants merge into a continuous hedge. Do not trim too closely, because many needle-bearing evergreens do not easily generate new growth from old wood.
These questions often arise: “How often should this hedge be trimmed?” and “When should I trim?” Answers depend to some extent on how formal an appearance is desired. In general, trim before the growth exceeds 1 foot. Hedges of slow-growing plants, such as boxwood, need trimming sooner. Excessive untrimmed growth will kill leaves beneath, and also pull the hedge out of shape. This is especially true with weak-stemmed shrubs. In the mountain and cooler areas, yews and other evergreens may need shearing only once annually, and then not before July; in milder areas, two or even three shearings may be necessary. Deciduous material should be trimmed earlier than July, but after the spring flush of new growth, and will often need to be trimmed once or twice more. Frequency depends on the kind of shrub, season, and degree of neatness desired.
What can be done with a large, overgrown, bare-bottomed, and misshapen hedge? If it is deciduous, the answer is fairly simple. In the spring, before leaves appear, prune to one foot below the desired height. Then trim carefully for the next few years to give it the shape and fullness desired. Occasionally, hedge plants may have declined too much to recover from this treatment; replacing them may be necessary.
Rejuvenating evergreen hedges is more difficult. As a rule, evergreens cannot stand the severe pruning described above. Arborvitae and yew are exceptions; other evergreen hedges may have to be replaced.
What tools should be used to trim hedges? The traditional pair of scissor-action hedge shears is still the best all-round tool. It will cut cleaner and closer than electric trimmers, which often break and tear twigs. Hand shears can be used on any type of hedge, while electric trimmers do poorly on large-leaved and wiry-twigged varieties, and sometimes jam on thick twigs. Hand shears are also quieter and safer, less likely to gouge the hedge or the operator. Hand pruners are useful for removing a few stray branches. Larger branches can be removed with loppers and/or a pruning saw.
Pruning RosesTop

All roses need some type of pruning. If roses are not pruned for a number of years, plants deteriorate in appearance, often develop more than the usual disease and insect problems, and the flowers become smaller and smaller.
Hybrid Tea, Grandiflora, and Floribunda roses require annual pruning in the spring, after winter protection has been removed. As a guideline, follow the old saying that roses are pruned when the forsythia blooms. If rosebushes are pruned too early, injury from repeated frost may make a second pruning necessary.
The only tools necessary are sharp hand pruners and gloves. If the rose collection is large, a small saw and loppers will also help. Loppers are used to cut out large dead canes.
Remove branches that are dead, damaged, diseased, thin, weak, growing inward, and cross or interfere with other branches. Proper pruning encourages new growth from the base making the plant healthy, attractive, and result in large blossoms. Cut at least 1 inch below damaged areas. Remove all weak shoots. If two branches rub or are close enough that they will do so soon, remove one. On old, heavy bushes, cut out one or two of the oldest canes each year.
Cut back the remaining canes. The height to which a rose should be cut will vary depending upon the normal habit of the particular cultivar. The average pruning height for Floribundas and Hybrid Teas is between 12 and 18 inches, but taller growing Hybrids and most Grandifloras may be left at 2 feet.
Make cuts at 45-degree angles above a strong outer bud. Aim the cut upward from the inner side of the bush to push growth outward and promote healthy shoots and quality flowers.
Other types of roses have special pruning needs:
A rose standard, or tree rose, is a Hybrid Tea, Grandiflora, or Floribunda budded at the top of a tall trunk. Prune tree roses as you do Hybrid Teas, cutting the branches to within 6 to 10 inches of the base of the crown in order to encourage rounded, compact, vigorous new growth.
Miniature roses are 6 to 12 inches high, with tiny blooms and foliage. Miniature roses do not need special pruning. Just cut out dead growth and remove the hips.
Old-fashioned Rambler roses have clusters of flowers, each usually less than 2 inches across. They often produce canes 10 to 15 feet long in one season. Ramblers produce best on year-old wood, so that this year’s choice blooms come on last year’s growth. Prune immediately after flowering. Remove some of the large, old canes. Tie new canes to a support for the next year.
Large-flowering climbing roses have flowers more than 2 inches across, borne on wood that is 2 or more years old. Canes are larger and sturdier than those of Ramblers. Many flower just once in June, but some, called ever-blooming climbers, flower more or less continuously. This group should be pruned in autumn, any time before cold weather sets in. First cut out dead and diseased canes. After this, remove 1 or 2 of the oldest canes each season to make room for new canes. The laterals, or side shoots, are shortened 3 to 6 inches after flowering. If the plant is strong, keep 5 to 8 main canes, which should be tied to the trellis, fence, wall, or other support. If it is not strong, leave fewer canes.
Pruning Shade TreesTop

Young shade trees may not need to be pruned to develop a good framework. Mature trees are generally pruned only for sanitation, safety, or reasons of size restriction. Trees can be pruned at any time of the year. A few trees bleed profusely when pruned in late winter. Among these are dogwood. The bleeding has no harmful effect, but is unsightly. In winter, an experienced tree professional can easily distinguish between live and dead wood. Winter pruning is often preferred because it is easy to visualize shaping when foliage is gone. Such work can also be done at lower cost in winter because fewer precautions are necessary to avoid garden and flower bed damage, and cleanup is easier.
Pruning Vines and GroundcoversTop

The pruning of ornamental vines is similar to the pruning of ornamental shrubs. Flowering vines are pruned according to flower production; those that flower on new wood are pruned before new growth begins, those that flower on last season’s growth are pruned immediately after flowering.
Vines that are grown for foliage are pruned to control growth and direction. Timing is less critical than for flowering vines.
Ground cover plants require very little pruning. Dead or damaged stems should be removed whenever observed. Some trailing ground covers, such as English ivy, may need pruning to prevent encroachment on lawn areas or other plants. With liriope, a grass-like ground cover, appearance is improved by an annual pruning. Before new leaves are an inch tall, remove the dead leaves from the previous year. For large liriope plantings, a lawnmower set to cut above the new leaf tips will speed this early spring job.

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