There's no reason to be 'prunaphobic'
BY JOE LAMP'L DIY Network

Many people fear pruning and, more often than not, it's simply because they don't understand the concept of cutting something back to help it grow more! It's counterintuitive, and it once was that way for me, too. Why would you cut something back that looks perfectly healthy?

I've had any numbers of friends I'd describe as "prunaphobic" But a basic understanding of the following principles equipped them - and it will you, too - to prune with confidence.

First, why prune?

Pruning is done for several reasons: to control size or shape, to remove dead or diseased branches or limbs, to improve structure or to stimulate new growth or flowering.

Pruning also can improve the health and look of a plant by allowing more light and air into the center.

So, contrary to what many think, cutting or pruning a tree, shrub or plant can be good for it by stimulating healthy new growth.

When a terminal bud or growing tip is removed from the parent plant, a growth suppression hormone called auxin is removed as well. Auxin, which is located in the terminal buds, suppresses the growth of other buds, signaling them to remain dormant. By removing the tip, nearby buds are no longer suppressed and may grow rapidly in response.

This lack of auxin allows new buds or branches to begin to grow, quickly replacing the one removed. If leaf buds are present on both sides of the branch, you will likely get two or more new branches for each one that is cut.

Timing is everything, though.

As you consider whether to prune a particular plant, you should know that there are better times of the year to prune.

Early spring is generally the best time to prune, just prior to new growth starting to develop. Most plants and trees utilize stored energy from fall and winter and will produce new growth just below the pruning cut.

Late winter, before any new growth occurs, is the next best time. Although pruning does stimulate new growth, in winter plants typically will not break dormancy until temperatures signal the appropriate time, even if pruning has recently taken place.

Early to mid-summer, after full leaf expansion, is an acceptable time. However, much of a plant's stored energy has gone into producing the new growth of spring. If you cut this new growth off, you've wasted the plant's energy.

It will then be stimulated to put on new growth, but the normal reserves for this process may have become depleted. This extra demand can be stressful to the plant in summer when conditions are likely to be dry and hot.

The least favorable time to prune is in early to mid fall. Pruning at this time can signal the plant to produce new growth, just as it is sending nutrients and energy into reserves for the cold months ahead. Not only can valuable reserves be diverted back into new growth, new growth can be damaged or killed by colder temperatures. This is especially true for evergreens. Any damage at this point could also create access points for over-wintering pests and diseases.

Special considerations should be given flowering shrubs.

I'm often asked why someone's flowering shrubs aren't blooming. In most cases it comes down to only one of two reasons. Either the plant isn't getting enough sunlight, or it's been pruned at the improper time.

Proper timing of pruning needs to be considered for flowering shrubs. Certain shrubs bloom on new wood. These shrubs produce flowers on the current season's growth. They can be pruned in late winter and still produce flowers the same year. Examples include butterfly bush, abelia and clethera.

(Distributed by Scripps Howard News Service.)