Here's a step-by-step guide.
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Colorful Crepe Myrtle
Credit: Southern Living

Pruning crepe myrtle trees is a bit of a mystery since it should only happen on rare occasions. To prevent "crepe murder," or the destruction of your beautiful trees for the sake of shape, adhere to the policy that less is more. Avoid "topping" off the branches to make a uniform cut around the tree and instead focus on pruning select branches. In the South, this is particularly important as additional branches will provide a buffer during the colder winter months to allow your plant to show healthy growth in the spring. Here are step-by-step instructions for properly pruning crepe myrtles.

Considerations Before Getting Started

Your Pruning Goals

Before you prune anything, it's good to know what you're trying to accomplish. After all, you can always go back and cut more. My objective was to maintain well-spaced main trunks with handsome bark and thin out the center to permit accessible sunlight and air penetration. The branch spacing is correct if a bird can easily fly through the center of your crepe myrtle.

Pruning Tools

To correctly prune a mature crepe myrtle, you need three tools. The first tool is a hand pruner to clip twigs and branches less than a half-inch thick. Next, you'll need loppers to cut branches a half-inch to 1½ inches thick. Finally, use pole pruners or a pruning saw to cut branches more than 1½ inches thick.

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Factors To Consider When Pruning Crepe Myrtles

When To Cut

Late winter is the best time to prune a crepe myrtle because it's leafless, and you can easily see all the branches. It also blooms on new growth, so pruning now won't reduce blooming. It may increase it.

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What To Cut

Remove branches in the following order. Start with the branches coming up from the base. Move next to all side branches growing from the main trunks up to a height of at least four feet. After, prune all higher branches growing inward towards the tree's center—remember to cut all crossing, rubbing, and dead branches.

Another pruning consideration is branches that grow at awkward angles that detract from the tree's appearance. Always cut back to a larger trunk branch—don't leave stubs. Removing seedheads on the end of branches is optional. Leaving them doesn't reduce blooming—I keep mine.

When To Buy Crepe Myrtles

Select these trees while they are in bloom. Remember, they can vary significantly in size and bloom colors. Choose the right size for your landscape to help avoid the ultimate Southern gardening sin, "crepe murder" (severely pruning your tree to just a few sticks and ruining its natural form). Large selections (more than 20 feet tall) include 'Natchez' (white) and 'Miami' (pink). Medium selections (less than 20 feet tall) include 'Near East' (pink) and 'Regal Red' (deep red). Dwarf forms (less than three feet tall) include 'Centennial' (purple) and 'Chickasaw' (pink). Select a sunny location, and remember to mulch and water well to ease your tree into the landscape. Container-grown trees are easy to transport and transition into the garden well.

How To Prune Crepe Myrtles

Pruning Tips for Crepe Myrtles

Remove branches that are too close, cross, or rub each other. It is important not to prune the tops of crepe myrtle trees to make them bloom. Topping may yield larger flowers but does not increase the overall volume of blooms. Extreme topping often weak growth, bending, and breaking in summer rains.

You know how a crepe myrtle typically sprouts a thicket of suckers at the base each spring? Reach down now, and pull them off at ground level. That will keep your crepe myrtle from turning into a thick, unkempt shrub.

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Why do you need my advice? Because many of you take guidance from your unaware neighbors who prune their crepe myrtles to look like this.

Pruning Mistakes To Avoid

This novice practice is what I call "crepe murder." I didn't invent the term. The gardening term "crepe murder" turns beautiful trees into ugly stumps and prevents the formation of pretty, mottled bark on mature trunks. This mistake also creates a forest of skinny, whiplike shoots sprouts from the end of each ugly stump. These whips are too weak to hold up the flowers, so the branches often bend to the ground.

Another reason people butcher crepe myrtles is that they say their plants get too big—but you chose the wrong plant for the spot. Most popular crepe myrtle varieties ('Natchez,' 'Miami,' 'Sioux,' 'Dynamite,' Muskogee,' and 'Watermelon Red') grow at least 25-30 feet tall. Plant them out in the yard—not in front of your bay windows, or go for compact, lower-growing kinds, like 'Acoma,' 'Centennial,' 'Hopi,' 'Prairie Lace,' 'Victor,' and 'Zuni,' which are from the Petite Series from Monrovia.

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More on Crepe Murder

It's a high crime of horticulture–the senseless, annual chopping back of beautiful crepe myrtles. Drive through any Southern neighborhood in early spring.

Why do well-intentioned gardeners keep repeating this crime? Some people think they must prune off old seed heads to have blooms the following year. This idea is false. Others hack back these plants to keep them from getting too big. These folks must remember crepe myrtles are small trees, not foundation shrubs. The tree is planted in the wrong place if the plants seem to need pruning every other week to keep them from covering the windows. Finally, crepe murder is a copycat crime. Many people engage in it because they see their neighbors doing it.

People shorten crepe myrtles by six feet, turning beautiful trunks into thick, ugly stubs. Repeated pruning to the same point creates gnarled, knobby "knuckles" on the ends of the trunks—a thicket of long, weak, whiplike branches sprouts from each knuckle. These whips are too weak to support the flowers and hang straight down like cooked spaghetti.

Find out the mature height of a selection before planting it. If your crepe myrtle grows too big for its spot, move it to where it has more room. Or replace it with a dwarf or semidwarf selection. Prune only to maintain natural form. Select four or five well-spaced main trunks—remove any others at ground level. Train these trunks to grow upward and outward from the base of the plant. As they grow taller, gradually remove all side branches up to four to five feet. This growth exposes the smooth, handsome bark. Early each spring, remove weak, spindly growth and all the branches growing in toward the center of the plant. Prune large branches back to a crotch. Never leave thick stubs.

How To Care for Crepe Myrtles Throughout the Seasons

Crepe Myrtles in the Fall

Blaze into autumn with summer's favorite tree. When people think of crepe myrtles, they envision warm summer days and pink, red, lavender, and white flower clusters sagging in the sun. But look at these classic trees in fall, and you might be surprised. Orange, red, and yellow foliage replaces the brilliant blooms for an outstanding autumn show.

Color Through Other Seasons

Crepe myrtles have rounded, light green leaves that emerge in the spring. As the weather warms, the foliage hardens off and turns dark green. Then, when the temperatures drop in the fall, leaves gradually transform from green to sparkling fall hues. Many gardeners select crepe myrtles by bloom colors, but you can also choose a plant by its fall foliage (see chart below).

Plant these beautiful trees in many colors and sizes to fit your needs and space. 'Chickasaw' and 'Victor' are dwarf trees that grow three to five feet tall, making them perfect for small gardens. 'Acoma,' 'Hopi,' and 'Zuni' are small trees and will grow seven to ten feet high. These can be planted in tight areas where you want a tree but have little space. Medium ones, such as 'Centennial Spirit,' 'Tuskegee,' and 'Yuma,' grow 15 to 20 feet tall and work well around sidewalks and terraces but can still be planted close to the house. Big crepe myrtles, such as 'Dynamite,' 'Natchez,' and 'Tuscarora,' will grow 20 feet or more. They make excellent street trees or to use in large yards. If you live in the Upper South, choose cold-hardy selections, such as 'Acoma,' 'Centennial Spirit,' or 'Hopi.'

Selection

Size

Fall Color

Bloom

‘Acoma'

10 feet

Purple-red

White

‘Centennial Spirit'

20 feet

Red-orange

Dark red

‘Chickasaw'

3 to 5 feet

Bronze-red

Pink-lavender

‘Dynamite'

20 or more feet

Red-orange

Cherry red

‘Hopi'

7 feet

Orange-red to dark red

Pink

‘Natchez'

30 feet

Orange-red

Pure white

‘Tuscarora'

25 feet

Red-orange

Dark pink

‘Tuskegee'

20 feet

Bright orange-red

Deep pink to red

‘Victor'

3 feet

Reddish yellow

Dark red

‘Yuma'

15 feet

Yellowish to brownish red

Medium lavender

‘Zuni'

9 feet

Orange-red to dark red

Medium lavender

How to Plant a Crepe Myrtle with Success: Step 3
Fill in around the roots with excavated soil, using your foot to firm it. Spread mulch 2 inches deep over the top. Water thoroughly using a hose, not a sprinkler.
| Credit: Photo: Van Chaplin

Growing Conditions

Crepe myrtles need full sun to perform well. They will grow in the shade, but blooms will be sparse, and plants will get leggy. These hardy trees have few pest or disease problems and require little water and fertilizer.

Also, crepe myrtles need minimal pruning. Some gardeners top them annually, which ruins their natural shape and beauty. Remove the sucker growth that sometimes appears around the base. Only prune to shape trees or to take out any cross branching. In the winter, you can remove old seedpods by clipping the tips of branches.

Summer blooms and fall colors make crepe myrtles a garden favorite. As the leaves disappear in winter, beautiful exfoliating bark will emerge, which decorates their gracefully sculpted trunks. For year-round interest, remember this Southern classic. Plant one now, and watch your tree change with the seasons.—Charlie Thigpen

Alkaline Soil and Crepe Myrtles

Not all soils in the South pass the acid test. Some turn oak trees yellow and cause the leaves of azaleas and gardenias to become yellow between the veins. These soils do this because they're alkaline.

What's alkaline soil? It's soil with a pH above the neutral point of seven (a pH below seven is considered acid). It typically occurs in regions with sparse rainfall, such as West and North Texas and western Oklahoma. But it also happens where beds of ancient limestone lie just beneath the surface. People often refer to alkaline soil as "limy" or "chalky." Limestone deposits occur in every Southern state except Louisiana. The soil in many parts of Missouri, Texas, Kentucky, Tennessee, and Florida is alkaline.

Alkaline soil affects plants by increasing the availability of some soil nutrients while holding back on others. For example, alkaline soils supply plants with plenty of calcium and magnesium. But it's stingy with zinc, manganese, and sulfur. These shortfalls can stunt certain plants. The primary nutrient most commonly deficient in high pH soil is iron. Lack of iron causes chlorosis (yellow leaves with green veins). Severe chlorosis eventually kills plants.

To determine for sure whether your soil is alkaline, have it tested. You'll find simple soil-test kits at garden centers, nurseries, and home supply stores. If you discover your soil is indeed alkaline, you have two options. The first is to replace the existing soil with acid soil entirely so that you can grow acid-loving plants. But this is laborious and expensive and seldom succeeds over time. A far better solution is to select plants that like alkaline soil. There are lots to choose from, and many are carefree, drought-tolerant native plants.

Try crepe myrtle or chaste tree if you need a small tree with showy summer blooms. Both tolerate drought and are easy to grow.