is an important maintenance practice for some evergreens. However,
pruning can be kept to a minimum by the wise use and proper placement
of plant materials in the landscape design. Evergreen plants can
be divided into two broad categories: (1) Narrowleaf (needled) evergreens
such as pines, junipers and yews; (2) Broadleaf evergreens such
as rhododendrons, hollies and box. The narrowleaf evergreens are
generally grow more rapidly than broadleaf evegreens, include many
tree forms and are commonly grown for their foliage only. Broadleaf
evergreens include many shrub forms and are often grown for their
flowers and fruit as well as for their foliage.
Limit the pruning of most evergreens to the removal of dead, diseased
and mechanically injured wood and to the maintenance of the natural
shape of the plants. Formal effects such as clipped hedges, topiary
and espaliers require regular attention and special equipment.
Dead, diseased and broken wood can be removed at any time of year.
The best time for general pruning is in late winter or early spring,
immediately before growth resumes. Narrowleaf evergreens may be
pruned a second time in June before the new growth has matured.
It may be necessary to give particularly fast-growing plants an
additional light pruning or two during the growing season. Good
judgment must be exercised when pruning flowering evergreens so
as not to drastically reduce the amount of next season's flowering
woodÜany pruning should be done as soon after flowering as possible.
Severe pruning can usually be avoided if pruning is done annually.
It is important to have the necessary tools in proper working order
for pruning your plants. These tools include a hand pruner, lopping
shears, hedge shears and a curved pruning saw. Narrowleaf evergreens
are characterized by growth that is either whorled or random (non-whorled).
When pruning pines, make cuts just above the needle whorls. Most
new lateral growth is stimulated at these points rather than along
the stems between the whorls.
pruning most other needled and broadleaf evergreens, cuts can be
made at any point along the branch, but care should be taken not
to cut too far back into the older wood, because new growth is not
as readily produced from such wood. When selectively pruning, it
is a good practice to cut the growth back to a side shoot. Some
evergreen species withstand relatively heavy pruning. This is true
of such plants as Japanese yew, box and evergreen privet. These
plants can be sheared, which involves the uniform removal of new
growth to make a plant conform to a prescribed shape. Because shearing
encourages the formation of additional lateral growth, a more dense
habit of growth is created. The amount and manner of pruning depend
to a large extent on the type of plant, its location and the particular
tastes of the homeowner.
Prune in early spring. Make cuts just above needle whorls. Additional
pruning may be done before new growth hardens in June. Pines normally
require little pruning.
Spruces & Firs
Cuts may be made at any point along the younger portions of the
branches. The best time to prune spruces and firs is in the early
spring. Pruning is necessary to maintain the natural shape of the
Juniper, camaecyparis and arborvitae
This group consists of many tree, shrub and prostrate forms. These
species can withstand relatively heavy pruning and many may be trained
into various forms by shearing. Early spring pruning is best, but
additional light pruning later in the season may be necessary.
Yew and hemlock
It is preferable to allow these plants to retain their natural form,
but both respond well to heavy pruning and shearing. Yews are able
to withstand exceptionally severe pruning into the older wood. Early
spring is the best time for pruning, although occasional light pruning
later in the season may be necessary.
Rhododendron, azalea, pieris and mountain laurel These
plants generally require very little pruning, as they are slow-growing.
Old flower clusters should be removed immediately after flowering.
Prune out only dead, diseased, weak or wayward branches.
Box, evergreen privet, barberry and pyracantha
With the exception of box, these species grow rather rapidly. All
these plants will stand heavy pruning, which is best done in early
spring. Because they are generally quite vigorous, additional trimming
during the growing season may be advisable.
These plants include both tree and shrub forms. American holly may
be pruned in December for Christmas greens. Chinese holly is also
a source of attractive greens and may be trimmed in the early spring.
When pruning American holly, always make the cut at a node, just
above a lateral bud. Prune so as to maintain the natural shape of
the tree. The shrubby Chinese and Japanese hollies can be more severely
pruned and may require some additional light pruning during the
Mahonia and leucothoe
These are rather slow-growing plants which require little annual
pruning--if pruning is necessary, do it immediately after these
plants flower in the spring.
from the Delaware Cooperative Extension, 2000