Crapemyrtles are among the most beautiful trees in the urban forest. They come in many shapes, sizes, and floral colors. But, there is a misconception that severely pruning a crapemyrtle is a good tree care practice. Wrong! Just about every landscape horticulturalist or arborist will tell you that topping Crapemyrtles is not only bad for the plant, but is a waste of your time and money.
How Crapemyrtle Respond to Severe Pruning
The University of Florida actually looked at the effects different types of pruning have on several cultivars of Crapemyrtles. These pruning types included topping, tipping, and pollarding. They then compared the results with Crapemyrtles that where left unpruned. Here's what they learned. With some cultivars, radical pruning delayed flowering up to one month as compared to unpruned crapemyrtles. On some cultivars, topping and pollarding actually shortened the length of time each tree flowered. With some cultivars, the number of flowers decreased as pruning severity increased.
But, perhaps the most harmful result of a severely pruned crapemyrtle is the effect on tree health. There are three important facts to consider when pruning a tree. First, all pruning cuts will injure a tree, except with deadwood removal. Second, pruning cuts impact a tree’s life functions, such as the flow of plant hormones, solutes, and sugars that are essential to the tree's growth and health. Third, the larger, more severe, and numerous the cuts, the greater the risk for decay organisms to take root and to destroy healthy wood.
The bottom line is this. Topping or severely pruning a Crapemyrtle can reduce the number of flowers, delay the time blooming normally begins, and shorten the period they bloom. And on top of that, topping causes severe injuries to the plant and its functions!
How to Prune a Crapemyrtle
If a crapemyrtle is the right size and in the right place, it needs little or no pruning. There are occasions, though, when pruning may be necessary. Reasons include:
· removing branches that pose a risk to people or property
· removing crossed or rubbing branches
· removing dead, damaged, or diseased braches
· improving tree structure
Correct pruning should be done late during dormancy. All cuts should be made at the end of the branch collar. Don’t flush cut or leave long stubs.
To learn more, search “Crapemurder” online for articles, papers, and reports by universities, state natural resource agencies, and reputable professional institutions.
Credit Line: Village Trees, LLC (Nashville, Tennessee)