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Crape Myrtles
Few plants are as connected with the south as crape myrtles. These plants thrive in heat and humidity and have the potential to bloom all summer long with relatively little care. Lagerstroemia indica or as most know it, the common crape myrtle, was introduced from China and Korea in 1747. Widespread cultivation of the plants started in Charleston, South Carolina in 1786. Today, through hybridization and plant breeding the family of crape myrtles includes a diverse mix of plants, from ground cover forms which are no taller than 8-10 inches up to standard varieties which can grow thirty feet tall or more. Flower colors range from red, pink, purple or white. They are a staple in Arkansas landscapes. The common crape myrtle was already entrenched in southern landscapes when the Japanese crape myrtle, Lagerstroemia faurei, was brought to the United States in the 1950's. This cold-hardy crape myrtle had beautiful red bark and was resistant to powdery mildew - a common disease of the crape myrtle. The only downside to the new introduction was it only came in one color - white. Dr. Don Egolf , plant breeder extraordinaire at the National Arboretum in Washington, D. C., began an extensive breeding program on crape myrtles, crossing the L. faurei with L. indica. The goal of the breeding program was to combine the beautiful bark color, cold hardiness, and disease resistance of the Japanese crape myrtle with the variety of flower colors of the common crape myrtle. Egolf made thousands of crosses between the two species and came up with many new forms of crape myrtles. Thanks to these efforts, the National Arboretum has released more than 29 varieties into the nursery trade. The University of Arkansas also has released several varieties of crape myrtles including 'Centennial', 'Hope', and 'Victor.' The most popular variety from Egolf's trials was 'Natchez.' This standard crape myrtle can grow 30 feet tall or more and has outstanding cinnamon-colored bark with white flowers. The first true miniature was discovered in 1989, and named 'Chickasaw.' This pink flowering plant grows no taller than 20 inches and spreads 26 inches wide. Today, new varieties and forms of crape myrtles hit the market annually.
Trying to keep up with what is available can be difficult. The National
Arboretum has compiled a chart as a quick guide to differences between their 29
released crape myrtles: including descriptions of flower color, bark color, fall
color, plant size, and growth habit. You can view it at:
http://www.usna.usda.gov/PhotoGallery/CrapemyrtleGallery/ While crape myrtles are easy plants to grow, they do have their problems. No.1 is the gardener in charge of pruning them. "Crape murder" is a common refrain and visible signs of this dot our landscapes - usually more commonly seen when the plants are devoid of leaves. Repeatedly cutting standard, large growing forms back to large knobby growths in the winter, is a common practice gardeners use to keep the plants the size they want them. If the plant is getting too tall each year, and you have to prune them to keep them out of the eaves of your house, then you planted the wrong variety. With proper selection, you can choose plants that at maturity fit the size you need. Trying to tame a tree into a shrub is a constant battle.
When choosing plants you really should read the tag and determine how tall the plant is predicted to grow at maturity. Choosing a plant that fits your location can greatly reduce your maintenance chores and give you a better-looking plant. What is the problem with heavy pruning annually? Luckily for the crape myrtle, it doesn't seem to cause them any harm, as they bounce back annually from devastating haircuts. Severe pruning actually encourages faster new growth. Instead of having three to five main trunks with beautiful exfoliating bark, you typically get five or six sprouts on each trunk and the plants become a large shrub instead of a stately small tree. The sheared plants grow fast and give you plenty of dense foliage growth. If you have an older variety that is susceptible to powdery mildew, all of that dense growth can increase your chances and severity of the disease. Masses of foliage reduce air low and keep the humidity level higher inside the plant, leading to more disease. Rapid new growth also produces large flower heads. While that may seem like a benefit to hard pruning, the large flower heads are borne on tender weak stems that can't support the weight of the bloom, so you end up with weeping crape myrtles instead of upright plants. Crape myrtles thrive in full sun. They will live in the shade, but don't expect any flowers. They are very drought tolerant once established, but will do well with a little extra water if it gets dry. They are not heavy feeders.
Don't be alarmed if your plants start having peeling bark. This is a sign that your plant has "come of age." The peeling outer bark showcases beautiful rich red, tan or gray colored wood. Once you have large, established forms, annual pruning is not needed; however, thinning or removal of suckers is common. If you allow the suckers to grow at the base, you will lose the tree form. Don't use herbicides to control these suckers, just prune them off. If you can reach the flower heads as they fade, deadheading or removing the spent flowers during the summer will encourage more flowers on your trees. Aphids tend to attack crape myrtles when it is hot and dry. These insects
suck sap out of the leaves and excrete a sweet substance called honeydew. Where
the honeydew falls on the leaves, a black sooty mold will form. While it can
detract from the overall beauty of the plant, it doesn't hurt them. A strong
spray of water or insecticidal soap can help to control the insects. You might be surprised to know that the Arkansas Champion crape myrtle is located in the front yard of a home in Pulaski County, and is 43 feet tall, with a 47 feet spread - so be aware that some species can get large. With proper selection and location crape myrtles give you beautiful flowers in the summer, outstanding fall foliage and beautiful bark in the winter. Related Links
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