Do you nip with caution when pruning a plants Or do you
ruthlessly attack? No matter what approach you take,
sometimes you just have to prune your plants. Here are the
most basic pruning principles to follow for fruit-producing
plants, other deciduous trees and shrubs, and evergreens.
Use sharp tools no matter what type of plant you're
pruning. Sharp tools make cleaner cuts that heal more
quickly. Make cuts on an angle and just above a node, where
the leaf attaches to the stem.
If you want to encourage branching, use heading cuts to
shorten existing stems. If you want to open an area to
light and air, use thinning cuts to completely remove some
stems.
On any plant, if you find stems or branches that are dead,
diseased or damaged, always cut them down to healthy
tissue. That said, let's move on to pruning guidelines for
various categories of plants.
Pruning is most critical for fruit trees. Young fruit
trees need a strong framework on which to hang their fruits
and to ensure their branches bask in plenty of
sugar-producing sunlight. Pruning fruit plants lessens
disease problems and, by removing some fruits, pumps more
flavor and size into those that remain. With few
exceptions, prune fruit plants while they are dormant.
With a young fruit tree, preserve branches that are 6
inches apart and that make wide angles with the trunk. If
the tree is initially a single stem, at planting, cut back
that stem to 2 to 3 feet above ground level, then select
side branches as the plant grows.
If the tree already has branches, save those that are
wide-angled and in good positions, but remove all others.
Shorten those you save to a few inches.
Do no more pruning on a young tree than is absolutely
needed or you will delay fruiting.
Mature fruit trees need annual pruning. The amount to
remove depends on the size of the particular fruit and the
bearing habit of the tree. Cherries, for instance, are
small and are borne on older stems, so the plants need
little pruning. Peaches, in contrast, are large and are
borne only on 1-year-old wood, so they need severe annual
pruning to thin fruits and stimulate new shoots that can
bear the following year's crop.
Prune raspberries and other fruit bushes little or not at
all when they are young, then annually remove the oldest
wood and thin out the youngest wood. The younger the wood
on which most fruits are borne and the more new shoots that
grow each year from ground level, the more severe the
annual pruning will need to be.
At planting, cut grapes and other vines back to a few buds
to channel energy into growing a single stem (sometimes
two). From then on, training depends on the type of fruit
and the kind of trellis or arbor you provide.
New fruiting stems arise where old stems are cut back to
within a few buds of permanent branches or the trunk.
Pruning Deciduous Shrubs
Most deciduous shrubs look best growing as a fountain of
stems. Because they naturally send up new stems from ground
level each year, they can be pruned so that old, decrepit
stems are in a continual state of replacement by young,
vigorous ones. Do not prune at all when the plants are
young. Despite all that is said and written about roses,
they are just another deciduous shrub and can he pruned as
such with fine results.
Prune with hand shears or a Topper, not hedge shears. Use a
Topper to cut some of the oldest suckers to the ground or
down to low. vigorous replacement shoots. How much to cut
varies from shrub to shrub. The more new suckers a plant
makes each year, the more suckers you have to remove.
Forsythia and red-twig dogwood both need more pruning than
witch hazel or smokebush.
Shorten lanky stems that arch all the way to the ground and
remove any overcrowded stems in the center of the shrub.
Prune shrubs that flower early in the season right after
their blossoms fade. Prune shrubs that flower from summer
onwards just before spring growth begins.
Pruning Deciduous Hedges
A few deciduous bushes make nice hedges, although many look
best grown informally rather than sheared. In either case,
their lack of leaves in winter is offset by their dense
twigs. Cut back plants drastically when you plant, to
promote low branching and vigorous growth. For formal
hedges, shorten main and secondary stems just before the
plants begin their second season of growth.
Shape formal hedges so that planes are narrower at their
tops than at their bottoms.
This allows light to bathe all parts of the hedge so the
hedge doesn't thin out at its ankles. Shear mature, formal
hedges after their spring flush of growth, almost back to
where growth began for that season. Prune informal hedges
the same as individual shrubs: Each year, remove some older
stems at the plants' bases, thin out excess young stems and
shorten stems that are too long.
Pruning Deciduous Trees
Trees do eventually assert their individual character as
they age, but early training can be important for long-term
strength and beauty. Except for small trees that develop
multiple trunks, allow only one vertical shoot to become
the trunk, then the central leader (the main vertical
branch) running up through the tree. Bend down, cut back,
or cut off any competitors. Also use this strategy for
coniferous and broadleaf evergreen trees.
For scaffold branches — the future side limbs —
select stems that are thinner than the central leader and
spaced 1 to 2 feet apart. The height of the lowest scaffold
limb depends on how high a head you want. Scaffold limbs
will grow thicker, but their aboveground height never
changes.
Allow weak temporary branches to remain along the
developing trunk and central leader to help thicken and
protect the branches from sunburn. Remove these temporary
branches after a couple of years.
Prune the developing tree as little as possible. You want
growth, and any pruning stunts growth to some degree.
Use thinning cuts to reduce or maintain size and let light
and air into the crown of a mature or overgrown tree.
Pruning Coniferous Trees and Bushes
Generally, coniferous evergreens need little pruning when
being trained or after they mature, especially if you plant
one suited to the site. There are so many shapes and sizes
available for most kinds of conifers that it's often
possible to select a plant that will just fit its intended
space and require no pruning.
To contain growth or make a plant smaller, prune just
before growth begins, cutting stems back to side branches
within the plant. Conifers vary in their ability to regrow
from old wood, so know or test a plant's response before
any drastic pruning. To make a plant denser, shorten new
spring growth before the plant has fully expanded.
Pruning Broadleaf Evergreen Trees and Bushes
Like conifers, broadleaf evergreens need little pruning
— especially if you plant one suited to the site.
As with coniferous trees, prune just before growth begins,
and cut stems back to side branches. Broadleaf evergreens
vary in their ability to send out new shoots from old stems
that are cut back. To make a plant denser, pinch the tips
of growing shoots.
Once you get the hang of pruning and are pleased with the
results, you might want to learn even more about how this
procedure can help a tree develop the healthiest structure
possible. You also might want to experiment with some
specialized design techniques, such as using pruning to
create a pleached tunnel of ironwood trees or a living
fence of espalier currants.
This article is adapted from Lee Reich's
The Pruning Book. See
MOTHER'S Bookshelf, page 129 in this issue, to order.
Gradual Renovation of a Neglected Shrub
First Year:
Thin the youngest stems and cut away some of the oldest stems.
Second and Subsequent Years:
Repeat the first-year sequence.
New wood gradually replaces old wood, and growth fills in at the base of the plant.
