The winter months are the ideal time to correctly prune crape myrtles, for maintenance purposes and for reversing the damage caused by topping or "crape murder". One of New Garden's core principles is to practice correct and beneficial horticultural techniques, and improper crape myrtle pruning is one incorrect technique that our maintenance crews see and must correct frequently. Let's look at how this practice has claimed the potential beauty of thousands--even millions--of innocent crape myrtles.
Crape Myrtle is the most popular flowering tree in the American south. It is showy, tough, drought tolerant, and subject to few plant pests. It's most destructive pest is probably the gardener or landscaper who, through unawareness (forgivable) or plain old habit (not so forgivable), continues the destructive pruning technique of crape murder.
Why has the practice continued in this enlightened age? Most likely it's self-perpetuating; people see it done everywhere so they assume it's the right thing to do for their crape myrtles. Sadly, it is not. A naturally growing, correctly pruned crape myrtle has a beautiful vase-shaped form with gently arching branches and lovely cinnamon- and silver-grey mottled bark. That beautiful bark and the elegant trunk and branches that show it off do not develop to the fullest potential when "murdered". Crape myrtle flowers can last for up to three months, and while it's true that crape murder does result in larger (but fewer) flowers, the thin branches that result from improper pruning cannot support them. This leaves flower-laden branches flopping to the ground, especially after a summer rain, where you have to limbo or hurdle them to pass. In winter the knobby, misshapen stumps create a less than pleasing silhouette in the landscape.
In reality, proper pruning of crape myrtle involves little if any cutting of the main trunk, focusing instead on removing thin and poorly placed branches and opening up the center for better air circulation. A well pruned crape myrtle should not look like it has been "pruned" at all. Branches removed should be removed back to the larger branch or trunk, leaving no stump. Here are the basics:
- Remove all suckers from the base.
- Remove side branches from the main trunk up to four feet or so.
- Remove higher branches that grow inward toward the center of the tree instead of outward, and any crossing or rubbing branches.
- You can remove seed pods if you don't like the look of them, but it will not affect flowering the following year. Plus it's a tough job on a larger crape myrtle tree. However, removing green seed pods immediately after summer bloom can encourage a second flush of flowers.
Stand back and look at the tree. Are there any dead branches, or branches growing in a weird direction that should also be removed? No? Good-you're done. And your crape looks great!
What if it's too late and your crape is already murdered? Is there any hope? Rest easy-in most cases you can repair previous poor pruning. It will take a few years to reverse the damage but here's what to do: Prune off the knobs, leaving clean trunks. For a more natural look, vary the height of the cuts a bit. In spring the trunks will sprout new growth. Select one or two sprouts per trunk only and prune off the rest. Let those shoots develop into strong new trunks, and maintain them as described above. Remove any small sprouts that develop near the base of the shoots you chose to keep. In a few years the new sprouts will have thickened to nearly the size of the original trunk.
If crape murder is necessary because the tree is too tall if left to its own devices, you have to face the hard truth that the cultivar that's been planted is too large for the spot it's in. In part this may be because when the "newer" cultivars were developed they were introduced to market before the original plants had matured, and the stated heights were a guess based on the heights of the parent plants. In the landscape these cultivars got larger than anticipated. It may be necessary to remove the too-large crapes and replace them with a variety of a more suitable size.
As is frequently the case, nature knows how best to grow a tree, and our job is to guide it to its full beauty, not change the inherent nature. Hopefully you now recognize the signs of crape murder, and will become a valiant defender of defenseless crape myrtles everywhere.