By Trey Pitsenberger, co-owner
Pruning plants is for many people so intimidating
that they never do it. While this rarely causes a plant
to fail, it means that for some plants their full beauty
is not revealed. You have the power to direct the growth
pattern of trees, flowers, and shrubs.
The energy in a
plant constantly flows to the terminal buds throughout
the plant. By pinching out terminal buds you can direct
the growth of the plant. Pinch out buds on the right
side of the plant and, until new terminal buds are
formed, energy flows to the left side and to the top.
To be successful at pruning requires some study of
the growth of plants, and some experimental pruning.
The reaction to pruning differs between different kinds
of plants. With some plants pinching out a tip is followed
by a quick growth of buds just below the cut; in other
plants tip pinching is followed by growth of many lateral
twigs all along the tipped branch. It’s
a good idea to test the reaction to pruning by making
a minor cut or two before you attempt to change the structure
of the plant.
You can also direct growth when you cut
back a stem to a bud; the position of the bud determines
the direction of new growth. If the bud is on the right
side the new branch will grow to the right. You can make
a shrub more open or denser by selecting the position
of the buds below the cut.
Directing the growth of annuals and perennials
is a common practice. When planting annuals and perennials
such as zinnias, petunias, marigolds, geraniums, etc.
pinch out the tips, or terminal buds, for full, many
branched plants. Snapdragons should be pinched when they
have only 4 or 5 sets of leaves, marigolds and zinnias
when the first flower bud is formed. You direct the growth
again when you remove faded flowers. Annuals direct their
energy to seed production. To stop seed production and
increase the flowering, remove the faded flowers. When
pinching out faded flowers be sure to pinch below the
seed case and not just pulling out the blossom.
When pruning deciduous
shrubs and trees you are pruning for renewal. When
a portion of a dormant plant is removed, the remaining
parts of the plant will receive a larger share of the
food stored in the roots, trunk, and limbs. You don’t
stimulate root growth by pruning out top growth. The
new growth in spring is supported by food manufactured
in the previous summer. In late summer and fall, large
amounts of the food manufactured by the leaves are
stored in the roots, trunk, and limbs. Many deciduous
shrubs are pruned for gradual renewal by thinning out
old wood. Every year or two you take out a few of the
oldest canes at ground level. Removing old wood opens
the top to let light and air into the center of the
plant encouraging growth from the base that will eventually
renew the top.
shrubs are pruned in the dormant season. The flowers
are formed on new wood developed in the spring. Spring
flowering shrubs are pruned right after flowering as
their flowers are formed on last year’s
wood. If pruning is needed to keep plants in scale for
landscaping effects, do it in spring just before the
new growth starts. Prune to retain the natural form of
the plants. Selective thinning and heading back will
These are some of the basics of pruning.
When you are unsure of the right way to prune talk to
your favorite landscape professional for advice. Remember
it is better to prune a little less than needed than
to prune more than needed. Keep a light hand with pruning
until you become more confident.