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.
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
|Peaked and rounded tops hinder snow
||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
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
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.
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
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
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
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 years choice blooms come
on last years 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
Pruning Shade Trees
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 Groundcovers
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 seasons 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
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