Crape myrtles are among the most popular plants for landscaping in the South because they are easy to grow, hard to kill, and produce explosions of blooms that add a pop of color to any yard. But they’re not maintenance-free, and knowing how to prune crape myrtles properly is key to ensuring they bloom long and hard and that they grow gracefully and fully.
We’ll tell you how to nip and tuck to get the most out of your crape myrtle.
In this article:
- What is a crape myrtle
- Pruning, step by step
- Benefits of pruning
- When to prune
- When not to prune
- Crape murder
- Frequently asked questions
What is a crape myrtle?
The crape myrtle is a hardy deciduous plant that thrives in warm climates. It is common in the Southern regions of the United States. There are about 50 distinct species of crape myrtle, although only a handful widely appear in landscaping in the U.S. Among those, Natchez, Tuscarora, Muskogee and Tonto and a few others are considered high-performing varieties.
One of the appeals of the crape myrtle is that it can bloom for long periods, generally from mid July to early September. It produces dense canopies of colorful flowers in white and hues of red, purple, pink and more.
Its many branches and shoots and fast growth rate make it an easy plant to train and shape, provided that you do it correctly.
How to prune a crape myrtle in six steps
These are some of the horticulture basics to follow when pruning crape myrtle. Following these rules will help your trees become strong and beautiful.
Assemble the pruning tools. You need:
- Eye protection
- Hand pruner or shear for small branches
- Pole pruner for tall trees
- Tree saw
- A pair of loppers
- A ladder for tall trees
When pruning, always start from the bottom of the tree and work your way up to the canopy. Remove the old and thick branches that are less productive. Doing so will also increase air circulation and open the interior to sunlight, reducing the infestation of pests and diseases.
There are two basic pruning techniques that master gardeners use on crape myrtles. They are:
Renewal pruning is a more aggressive pruning approach that involves removing branches that are bowing out. It is done by cutting them at the point where they emerge from the trunk.
You need a tree saw or loppers because they are hard, and the hand pruner or shear may not get the job done.
As the name suggests, selective thinning involves removing some of the smaller lateral shoots from the main branches to reduce clutter and eliminate shoots that cross, rub or touch.
Remove the old, dormant, damaged, and sick limbs from your crape myrtle. It is hard for the damaged branch to recover, so it is better to chop it off. Inspect the limbs to see if they are sooty or infested with aphids that suck the tree sap. When removing the diseased branches, ensure you disinfect the pruner to avoid spreading the disease to other parts of the plant.
Prune all the weak and thin branches at their collars ( the transition point of the junction of the main branch and the trunk of the emerging branches) because they will not produce good flowers.
Then, remove the limbs that cross and rub and the large branches that grow toward the interior of the tree.
Pro Tip: You should remove less than 25 percent of the total shrub volume. Removing more than that may reduce flowering that year.
Prune all the dead flower heads from the previous season by about 15 centimeters. Remove the clusters with seed pods to allow new growth and increase the flowering rate.
Avoid shearing the exterior tips of the crape myrtle shrub. The plant will respond by creating multiple new stems at the point of a cut, leading to the formation of hedges. The hedges will block the sun from penetrating to the plant’s interior.
Benefits of pruning a crape myrtle
Like all trees, crape myrtles require periodic trimming. The key is to not simply lop off large sections, although many people do. That approach is euphemistically known as “crape murder” by most arborists and just harms the plant in the long run. More on that later in this article.
Crape myrtles have a beautiful natural growth pattern. The key is to aid this pattern by pruning just what’s needed.
Proper pruning is good for the plants’ health and their visual appeal. These benefits include:
- Removing diseased, damaged limbs promotes healthy growth.
- Pruning allows you to train and shape the canopy of the plant.
- Trimming rejuvenates the plant and encourages new growth.
- Eliminating excess branches allows the plant to receive more sunlight and increases air circulation.
- Preserves the plant’s natural shape.
When to prune a crape myrtle
You can prune away dead or diseased branches or twigs any time. But the very best time to prune is winter and early spring to promote new growth in your tree when the spring and summer roll around.
Pruning in late winter when the crape myrtle is ready to come out of its dormant stage will result in the best size and shape, and the most blooms. Pruning during this time will also help reduce the amount of sap lost.
When not to prune a crape myrtle
Pruning during the fall promotes new growth, which freezes during winter and damages the branches.
Don’t prune during summer, either, because it may lead to new growth when the plant should be hardening. The plant will also lose a lot of sap, which may weaken or kill it.
Don’t prune in late spring or you could interfere with the new growth.
What is ‘crape murder?’
It would be tempting to just “top” your crape myrtle (cut it down to its trunk). Many people do after the growing season, but it’s not good for the plant and ultimately results in a poor shape, fewer blooms and an unhealthy tree. Tree experts call this crape murder.
This approach involves a severe cut to a random height on the tree instead of pruning to another branch, stem, or bud. Bare stems can start to decay, causing irreversible damage to the tree. New branches will, indeed, sprout next growing season, but they will be too weak to support flower buds adequately and can even snap off in strong winds.
This approach also results in less bloom time because end shoots produce only one primary flower cluster instead of several.
Three words: Don’t do it.
Frequently Asked Questions. (FAQs)
The crape myrtle has varieties of cultivars. They can be of different heights, from dwarf to medium and tall trees. They require pruning to keep them in good shape. They thrive in warm climates, and have a moderately fast growth rate.
Topping a crape myrtle – or dramatically cutting it down after the growing season – is a common but misguided approach that weakens the tree overall, promotes weak new growth and reduces the amount of time the tree blooms in the spring and summer.
Pruning your crape myrtle judiciously promotes new growth and flowering and increases aeration. If you need somebody to take care of your crape myrtle, you can contact our Lawn Love lawn care professional for help.
Main photo credit: Alabama Extension / Flickr / Public domain