Now through early April is a good time to prune most leafy shrubs.  This pruning will “renew” the plants, keeping them young and vigorous.  It also helps plants to maintain their natural form.

Renewal Pruning

Once shrubs get about five years old, they will benefit from renewal pruning.  You can remove the oldest, thickest stems each year, cutting at ground level.

Keep in mind that pruning stimulates new growth wherever you make cuts.  By cutting at ground level, you will stimulate new growth from the base of the plant, thereby developing a fuller bush.  Try not to remove more than one-third of the growth during any single year.

Every situation is different, but usually it is best to prune out about 20% of the oldest canes every year.

New Shrubs

Young shrubs need very little pruning.  Only remove dead wood, broken branches, and branches that rub against one another.  After about five years, shrubs are well-established and require regular pruning.

Spring Bloomers

Lilacs, forsythia and other spring flowering shrubs are now loaded with flower buds.  You can prune them now, but you will be reducing your spring bloom.  Most gardeners wait to prune these shrubs immediately after they are done blooming.  Follow the same techniques described above under renewal pruning.

Overground shrubs

Sometimes it’s best to prune badly overgrown shrubs down to the ground.  This can be done for neglected forsythia, Annabelle hydrangea, honeysuckle, potentilla, privet and pink-flower spireas.  These plants will establish new growth quickly.  Severe pruning is best done during the dormant season.

Evergreen shrubs.

Evergreen branches can be removed during the dormant season.  Light trimming is best done after new growth begins in April or around the Fourth of July.  If you trim now, you may create wounds in the needles that will dry out and turn brown.