News from Bob's Market & Greenhouses, Inc.

Now is the time to prune spring-flowering shrubs like forsythia. However, for many, pruning can be a daunting task. I know I've had the experience of staring at a plant wondering what to cut. Here are some helpful tips to follow as you prune.

General maintenance
- Small branches that do not conform to the natural shape can be remove as needed. Deciduous plants are normally grown for their flower display. The best flowers are produced on vigorous new shoots while older branches produce few or no flowers. Removal of the oldest branches can be achieved by making thinning (removing an entire branch) and heading cuts (removing part of a branch). Plants vary in the frequency that older branches should be removed. Forsythia should be pruned annually while viburnum and witch hazel may not need this type of pruning more than once every five to six years.

Severe pruning- Older shrubs that have out grown their location may need a more severe pruning to reduce plant size. If they are healthy and receive adequate sunlight they should respond to renewal pruning. Pruning all the branches at or near the ground is the simplest procedure. An excessive number of new upright shoots may develop from the base by mid-summer. After these shoots have reached their full length, some of the shoots should be removed and some should be headed back. Prune to outward growing buds so the inner portion of the plant will not become overly dense.

An alternative is to selectively remove up to fifty percent of the branches at the base. This would include the removal of older, unproductive wood, inward growing branches, and any other growth that detracts from the natural form of the plant. Any extremely vigorous, unbranched suckers also would be removed. Examine the remaining branches and head back those that detract from the intended size or appearance. By mid-summer, new shoots should have developed. Some of the new basal shoots should be removed. A less dramatic method is to annually remove one-fourth to one-third of the oldest branches for several years until all of the old branches are remove. This method will also require the removal of excessive basal shoots in mid-summer.