‘Crape murder’ at its worst results in less-than-healthy trees. (Photo by Dan Gill)

For Release On Or After 03/07/14

By Dan Gill
LSU AgCenter Horticulturist

The term “crape murder” has been coined to describe the cutting back of crape myrtle trees. Although perhaps a little overly dramatic, it is in use by horticulturists across the Southeast wherever crape myrtles are a popular and common tree.

It seems you see crape myrtles being cut back all over the state. Perfectly beautiful crape myrtle trees are being disfigured and deformed for no good reason. In many cases, this annual pruning is needless work and expense that generates huge amounts of pruning trash that ends up in landfills. And it is not healthy for the trees in the long run.

Horticulturists are determined to educate the gardening public about this practice. One way to stop crape murder is to debunk the reasons why it is done.

Pruning misconceptions

This is the preferred or best way to prune a crape myrtle. Nothing could be further from the truth. For the overwhelming majority of situations, pruning only to enhance the natural shape of crape myrtles is most appropriate.

Crape myrtles bloom better when cut back. This is not accurate. The flower clusters may be larger on severely pruned trees. But the added weight on the ends of long branches causes them to bend over awkwardly, especially after a rain. These low-hanging flower heads can create problems and get in the way when a tree is planted near a driveway, sidewalk or path. And since the tree is smaller, it actually produces fewer flower clusters.

You can cut back a crape myrtle to change its shape. A wide variety of crape myrtle varieties are available today, and as you look around area landscapes you will see great diversity among them. Some grow tall and upright like a vase, while others are shorter and spreading, more like a mushroom. These shapes are controlled by genetics. You cannot make an upright-growing crape myrtle grow in the shape of a mushroom by cutting it back. So, if you want a crape myrtle that will mature the shape you desire, make sure you choose one that naturally grows that way.

Young crape myrtles should be cut back to make them look “fuller.” Young trees often appear more spindly and less substantial than older, well-established trees. But this is a matter of age, not something that needs to be corrected with pruning. Young crape myrtles are not supposed to look like older crape myrtles. Over time, young trees will attain the shapely, full canopies of older trees without drastic pruning.

You should cut back a crape myrtle to control its size. If the height of the crape myrtle is not causing a problem with a nearby structure or power lines, there is little reason to reduce a tree’s height. To cut a crape myrtle back for the vague reason of “it just seems too large” ignores the fact that these plants are trees. They are supposed to be relatively large. Nobody cuts back redbuds, silver bells, flowering cherries and other flowering trees just because they dared to grow into what they are – small trees. Why do we do it to crape myrtles?

Pruning properly

To prune a crape myrtle properly, first decide if it needs to be pruned. As with any pruning project, you must have a specific, valid purpose in mind before you begin. In other words, if you can’t come up with a good reason to prune your tree – leave it alone.

If you do see something that calls for pruning, study the tree carefully and determine what needs to be pruned to accomplish the specific purpose. If the problem is one branch is touching the edge of the roof, deal with that branch. Don’t cut back the whole tree.

Every crape myrtle will need some pruning in its life to grow properly and fit in well with its surroundings.

Over time, branches that are too low on a trunk will need to be pruned to raise the canopy to the desired height. We often need to remove weak, thin or vertical shoots from the inner part of the tree to produce a cleaner-looking tree.

Selected branches may need to be pruned back to a side branch or the trunk to create a shapelier tree and to eliminate crossed and rubbing branches. Generally, avoid cutting back or shortening branches much larger than your finger, although it’s fine to cut larger branches back to a side branch or to the trunk when needed.

Of course, you need to prune to remove suckers from the base of the trunk. This is especially important in younger trees.

You may also need to redirect the direction of a branch’s growth. This can be done by studying the branch carefully and looking for a side branch that grows in the desired direction. Prune back to that branch, and you have redirected the growth of the branch. This can be helpful where trees are too close to a structure, such as a house.

A common problem is crape myrtle trees being planted too close to a house – always locate trees at least 10 feet away from the house roof line. In situations where trees are close to a house and branches are hitting the roof, branches can be redirected to grow away from or up and over the roof by using this pruning technique.

We are so lucky to be able to grow these beautiful summer-flowering trees in our landscapes here in the South. Crape myrtle trees do not deserve to be butchered and disfigured by severe pruning. Help spread the word that cutting them back is not the right way to prune these trees, and maybe crape murder will not be so common.