Growings On: Pruning woody ornamentals

Published 8:00 am Wednesday, September 6, 2023

Pruning your ornamental plants is a necessary tool in your lawn care toolbox. There is also an art to it, as it’s not always easy to do.

Different plants respond differently to both timing and severity of pruning. Start by having a clear objective of what you want to accomplish when pruning. Do you want to change the shape of that shrub, has it completely overgrown it’s assigned space, or do you just want to “pretty it up”?

There are only two types of pruning cuts: thinning and heading. Thinning cuts tend to open up the plant canopy by entirely removing limbs at their base, and replacement growth, if any occurs, won’t fill the opening you’ve created. Fruit growers may use thinning cuts to let light and air penetrate the canopy to improve fruit color.

You make heading cuts by cutting back portions of shoots/limbs. Where each shoot is headed, bud breaks create two, three or four shoots from the remainder of the shoot you headed so the canopy gets thicker. A formal hedge is a good example of heading cuts.

Never prune woody plants in late fall through January, ideally get it done early so that new growth has time to harden off before winter. Woody plants pruned in October, November, December and January are far more susceptible to cold injury than if pruned in other months. If spring flowering plants require pruning, do it right after they flower. Prune plants that bloom in summer, fall and winter before they start growing in the spring.

Dormant pruning is an invigorating process, reducing the top area that roots have support, once it starts growing again. On the other hand, late spring pruning tends to devitalize the plant somewhat. That’s because stored reserves in the shoots, trunk and roots were heavily used to produce the new spring growth. In effect, you’ve removed part of the food-producing foliage before it can “pay back” the shoots, trunk and roots with food reserves.

If you select the right plant for the right place, you won’t have to prune as often. A vigorous growing large plant cannot be kept small by pruning forever, a small plant would be a better fit in some areas. Many landscape plants can be full, with thick canopy, in the sun but are often open and leggy in the shade. Pruning can’t correct this problem either.

University of Georgia Extension offers many publications on pruning and woody ornamental plants so if you have any questions feel free to contact your local county agent to get more information.

Brenda Jackson is the agricultural and natural resources agent for Murray County Extension. She can be contacted at (706) 695-3031 or bljack@uga.edu.