Crape Myrtle Grow Guide
Crape Myrtles (Lagerstroemia indica), often referred to as the “lilacs of the South”, are among the favorites of the South due to their showy flowers, colorful autumn black foliage, and, in many cases, their attractive bark. Let us not forget the other wonderful features they possess, such as crape myrtles being drought tolerant, fast growing and deer not usually being interested in them. Crape myrtles can be used as a large deciduous hedge or screen, if planted together, or as a distinctive focal point framing a gate warmly welcoming visitors. Does great framing a driveway or a fence! While growing crape myrtles is not an issue in areas they are hardy to, for your crape myrtle to truly flourish we’ve created this guide to steer you in the best route. They are slightly cold tolerate for some southern states.
Selecting the right crape myrtle for your landscaping needs means you have to take more than just the color into consideration. When choosing your crape myrtle, make sure to pay close attention to the plant’s mature height and width and if that fits the look you hope to achieve. This step will save you backaches and heartaches in the future. How fast do crape myrtles grow, do you ask? Check out this chart below for each cultivars specifics. Take note that the black diamond crape myrtle growth rate is about the same even though they are mostly bush-like trees.
Days of Flowering
|Arapaho||20′||10′||Cinnamon Brown||Orange||120+||Upright||Showy flowers|
Pest & disease resistant
Fast growth rate
|Miami||8-12′||10-12′||Chestnut Brown||Orange to Dark Russet||100||Upright||Grows like Natchez|
Attracts butterflies & hummingbirds
|Muskogee||25-30′||15-25′||Light Gray||Crimson Red-Orange||100||Broad-spreading||Disease resistant|
Blooms all summer
|Natchez||25-30′||15-25′||Cinnamon Brown||Crimson Red-Orange||100||Broad-spreading||Attractive white blooms|
Exfoliating, cinnamon colored bark
|Sioux||15-20′||10-15′||Coral Pink||Maroon||90||Upright; narrow||Showy pink flowers|
|Tonto||8-15′||6-10′||Taupe||Bright Maroon||75||Compact globose||Showy flowers|
|Tuscarora||18-25′||15-18′||Light Brown||Red-Orange||70||Vase; broad crown||Showy flowers|
|Red Rocket®||20-30′||10-15′||Gray/Cinnamon||Bronze Red||120||Bush-like||Showy red flowers|
|Black Diamond® Pure White™ Crape Myrtle||10-12′||8′||Light Gray||Black foliage||90||Bush-like||Uniquely colored foliage|
Bright white blooms
Great size for smaller gardens
|Black Diamond® Best Red™ Crape Myrtle||10-12′||8′||Light Gray||Black foliage||90||Bush-like||Deep red blooms|
Uniquely colored foliage
Great size for smaller gardens
|Black Diamond® Shell Pink™ Crape Myrtle||10-12′||8′||Light Gray||Black foliage||90||Bush-like||Uniquely colored foliage|
Bright pink blooms
Great size for smaller gardens
Check out this video on the Black Diamond Crape Myrtle varieties!
Choose the best place in the landscape for your new crape myrtle. Consider the ultimate size of the tree and note if there might eventually be problems with overhead wires, poles, structures or other desirable trees or shrubs. Perfect Plants’ Black Diamond crape myrtles get only 10-12 feet tall and spread just 8 feet across, but some of the older cultivars (such as ‘Natchez’, ‘Red Rocket’ and ‘Tuscarora’) get considerably larger. Crape myrtles do best in full sun – the sunnier the spot, the better, but they should get at least 6 hours of sun each day. Crape myrtles bloom poorly in partial sun and may not bloom at all in a mostly shady location. Crape myrtles like a soil that is relatively moist but still well drained. Once established, however, they do well in dry, sandy soils. Crape myrtles do not tolerate soils that stay waterlogged for extended periods.
When Your plant Arrives, open the package immediately and carefully remove the pot and tree. Inspect the tree for damage and if it’s in good shape (they almost always are!) water the soil if it is dry and place the pot in a shady or partly shady spot until you can plant it.
When planting your new tree, thoroughly water the soil in the plant’s pot before starting. Dig a hole larger than the pot, twice as wide if possible. Place the pot on its side and slide the plant out. If the plant is stuck, you can slip a long-bladed knife around the inside edge to loosen it. Gently loosen some of the roots along the sides and bottom, and pull them outward so they are not encircling the root mass. It shouldn’t be necessary to prune any of the roots.The exception is large root(s) wound around the circumference of the pot. In this case the offending root should be shortened so that when it is in the ground it will grow outward and not continue growing in a circle.
Build up a mound of soil in the middle of the planting hole. Place the new tree’s root crown on top of the mounded soil so that the stem will be at the same depth as it was in the pot. Spread the side roots out over the mounded soil while backfilling the hole. Work the soil in and around the roots. When the hole is half filled, give it and the roots a good soaking of water. When the water has drained, readjust the depth of the stem if necessary and finish filling the hole. Gently tamp the soil down with your hands.
Use your hands to build up a 3-6 inch high dike of soil around the outside of the root zone. This will help impound water over the roots while it sinks into the soil. Water thoroughly. Spread 3-6 inches of an organic mulch over the root zone to help hold in soil moisture. You can use hay, straw, leaves, pine needles, or grass clippings.
You may need to stake the new crape myrtle until its roots become established enough to keep it from falling over in strong wind. Drive 2 or 3 stakes into the ground 2-4 feet out from the trunk and use wire or twine to hold the trunk upright. Cover the wire where it attaches to the trunk with a section of old garden hose, cloth or other material to prevent it from damaging the bark. The attachment on the trunk should be loose enough to allow some movement; if the trunk is not allowed to move a little in the wind it will become weak. The supporting stakes are just to make sure the young plant doesn’t fall over completely. Supports usually can be removed after the first year.
Keep the young tree well watered during its first growing season. If planted in the winter months, you can water once a week. Planted during the growing season, a crape myrtle should get watered every 2 or 3 days for 3 or 4 months. If you’re having a dry spell, or your soil is sandy, you should water every day for the first 3 or 4 months. The most common reason for a newly planted tree to die is lack of enough water.
Once established (after a year of growth), crape myrtles can tolerate dry spells and should not need any supplemental watering in climates that average at least 20 inches of rain per year (which is all of the eastern US and much of the West). Crape myrtles benefit from an annual application of fertilizer, such as Nutricote Total Controlled Release Type 360 Fertilizer 18-6-8. Follow label directions and don’t over-fertilize, as this can result in excessive leaf growth, production of unsightly suckers and fewer flowers.
Some varieties of crape myrtle tend to produce suckers, slender fast growing shoots, at the base of the tree. If your desire is for a standard tree shape, the suckers should be pruned off as they appear. Otherwise, the crape may take on the shape of a bushy shrub. Crape myrtles bloom on their new growth each year, so any pruning of the main tree (as opposed to removing basal suckers) should be done during late winter when the tree is not growing. If you cut off new growth in spring, you cut off developing flowers. If you prune in autumn, the tree could begin new vigorous growth that will then be susceptible to freezing which could kill the tree. When it comes to pruning crape myrtles, there are two distinctly different schools of thought:
- Some like to cut them back all the way to a few of the largest limbs, leaving just a stubby skeleton. When growth resumes, these trees sprout numerous shoots from each stub and develop a rounded, lollipop-like shape that is covered in flowers. Crapes pruned this way are good for borders and hedges where uniform a height is desired. However, this “crape murder”, as some call it, results in thin, arching stems and destroys the architectural beauty that characterizes a free-growing crape myrtle.
- Most gardeners prefer to allow their crapes to grow into a more natural form, and very little pruning is ever needed. Limbs that cross and branches that are too long or too crowded can be pruned out to maintain a desirable shape. Cut the unwanted branch back to a branch that has at least 1/3, but preferably 1/2 or more, the diameter of the one you are cutting. This is called a thinning cut. If you merely lop off a branch anywhere (a heading cut), the plant will respond with numerous weak and unsightly shoots just below the cut. Pruning all the way back to a branch at least 1/3 the diameter allows the remaining branch to grow normally.
Either way you prune your crape myrtle, you will still be awarded with flowers. Some varieties of crape myrtle will produce a second or even third flush of flowers if the spent flowerheads are cut off soon after they have finished blooming.
Crape myrtles are sometimes attacked by aphids, and then sooty mold often grows on the aphid excrement. This gives the dark leaves a gray or brownish coating that is not harmful, but can be unsightly. Sometimes an aphid infestation becomes so extreme that the leaves are damaged and flowering may be impaired. You can control aphids by spraying with a soapy water solution. Chemical controls for aphids include insecticides that include malathion, diazinon, or ultra-fine horticultural oil. Follow label directions explicitly.
During warm humid weather that persists for several days and nights, crape myrtles sometimes are attacked by a fungus called powdery mildew. This looks like a grayish powdery fuzz on the leaves. It occurs especially on crape myrtles growing in damp and shady locations, where air circulation is poor. Powdery mildew is not fatal but can cause deformation of the leaves and stunted growth. It goes away when conditions become less hot and humid. The best way to control powdery mildew is to prevent it. If your crape myrtle is in full sun, and not crowded next to other plants, powdery mildew, which abhors fresh air and direct sun, should not be a problem. Some varieties of crape myrtle are resistant to powdery mildew. ‘Natchez’, ‘Sioux‘, ‘Tonto‘ and ‘Tuscarora‘ all have very good resistance to powdery mildew. If you decide you need to do something about powdery mildew on your crape myrtle, you can treat the foliage with a fungicide labeled for the purpose. Choose a copper-based fungicide, or one that contains myclobutanil, propiconazole or thiophanate-methyl. Follow the label directions exactly.