Prune Your Shrubs

The recent warm weather notwithstanding, January and February are usually the correct time to prune shrubs.  Pruning shrubs encourages them to grow, and so it’s best to wait for consistently cold weather before pruning them so they don’t put out new growth that cold weather will kill.  The weather forecast indicates that cooler weather will arrive later this week, and I hope the poor confused plants will remain dormant.  However, the honeybees enjoyed the weather and the blooms on my Mahonia over the weekend, and I have enjoyed the fragrance of my tea olive. 

According to my own experience and according to the Columbia Garden Club’s book “Gardening Notes for South Carolina,” January and early February are a good time to prune trees and shrubs that do not bloom in the spring such as evergreen shrubs and crape myrtles.  Do not commit “crape murder” by rounding off the top of the tree; crape myrtles are attractive trees both in the summer and in the winter as long as you allow them to retain their natural form.  I prune mine by cutting off branches that cross or are diseased or broken, but I leave the long graceful form of the branches alone.  I also thin the tree by cutting off branches at the trunk.  Thinning the tree allows air to circulate and helps prevent mold. 

“Prune after bloom” is a good rule of thumb, so do not prune forsythia, hydrangeas, azaleas, and camellias, among other spring-blooming shrubs, until after they bloom.  If you prune them before they bloom, you will cut of the flower buds and will have to wait until next year for blossoms. 

Because shrubs are dormant now, you can prune them without worrying that the pruning will spur new growth that the frost might kill.  On any shrub or tree, at any time of the year, you can remove dead, diseased, or broken branches.  You may have difficulty determining whether branches on deciduous trees or shrubs are dead or just dormant.  Bend the branch gently; if it is pliable, it is alive and if it snaps, it is dead.  Also, you may gently scratch the bark with your fingernail; a live branch is green inside and a dead branch is gray or brown.

Use hedge trimmers to shape boxwoods and hollies into squared-off shapes, if you prefer it, but please do not prune azaleas, camellias, forsythia, loropetalum, and other shrubs with graceful, flowing branches into little squares or balls.  Flowering shrubs are much more attractive, and easier to maintain, if you allow them to maintain their natural form.  Reduce size by cutting off entire branches with loppers, not by giving them a haircut with hedge trimmers. 

If you must prune shrubs several times a year to keep them under control, the repeated chore is a sign that you have a shrub in the wrong place.  It may be too big for its spot, or it may have an unruly nature in a place where you would like a neat shrub.  I prune most of my shrubs once a year.  The only shrubs that require trims that are more frequent are my ligustrum topiaries, but I expected the high maintenance when I purchased them.  Now is the best time to move any shrubs or trees; dig up as big a root ball as possible when you remove it, and water the shrub well throughout the winter and the coming summer.  I have moved large shrubs with success.