Troy Landry and the Crepe Myrtle Connection: What Southern Gardeners Can Learn From Swamp Country
Troy Landry is the Louisiana alligator hunter from the History Channel show “Swamp People‚” and he has never claimed to be a horticulturist‚ but his piece of the Atchafalaya Basin is really not all that different from a Tennessee backyard‚ horticulturally speaking․ They're both in a horticultural zone where crepe myrtles absolutely thrive‚ and that's really the thread worth pulling on here․
Often called the "King of the Swamp"‚ Landry has spent thousands of hours hunting alligators in the south Louisiana bayous with his two sons‚ Jacob Landry and Chase Landry‚ alligators in the 30-day south Louisiana alligator season and is known for reading water‚ weather and gator behavior better than almost anyone on television․ That instinct for understanding a landscape‚ and knowing what grows where and why‚ is the same instinct you need‚ whether you're working in the swamps or on a quarter-acre lot in Nashville․
Reasons for similarities between Louisiana and Tennessee plants․
The USDA hardiness zones for the Atchafalaya Basin in Louisiana are 9a and 9b․ It is a hot humid swamp․ Middle and West Tennessee hold USDA zones 6b-7b‚ considerably cooler but warm enough for most of these plants to survive‚ including various crape myrtles‚ which are best of all․ The tree has tolerated the hot and humid summers of southern Louisiana and the more temperate and still muggy growing season of Tennessee and done so without much fuss․
That range is rare․ Most zone 9 ornamentals freeze to death in a zone 6 winter․ Zone 6 ornamentals often do not perform in the humidity and heat index further south․ This is why crepe myrtles have become the flowering tree of choice in the mid-South and in the Gulf region․
Why crepe myrtles are so well-suited here
If a crepe myrtle is planted in the ground in Tennessee during April‚ it may bloom in the early to middle part of June and may continue blooming approximately until September for some cultivars․ Three or four months of blooms is more than almost any other flowering tree in this climate․
The most important thing for getting them established is:
Fall planting‚ during the months of October through early December‚ is the best time to plant a crepe myrtle‚ as the new root system has time for development during their winter dormancy․ However‚ these trees can also be planted in the spring if done early in the month of April‚ before summer heat begins to stress the new root ball․
Sun․ This tree will need six hours of direct sunlight each day․ The other thing is putting it in shade․ If you plant a crepe myrtle in half shade‚ you wind up with a leggy spindly tree that gets a fraction of the flowers․ This is the single most common mistake we see - anyone who plants a crepe myrtle under the edge of a tree canopy because it looks like a nice spot wonders why they never flower well․
Soil drainage․ Crepe myrtles‚ while loving moisture‚ do not do well when their roots remain wet for long․ The clay-like soil that covers most of the middle of Tennessee requires compost use to prevent standing water from heavy spring rains from rotting the plant's roots․
Size at maturity․ This varies enormously by variety and is where a lot of buyers get surprised․ Standard trees such as Natchez and Muskogee reach a typical height and spread of 20 to 25 feet․ Dwarf and semi-dwarf forms such as Pocomoke and Chickasaw grow to a height and width of 3 to 8 feet ‚ and are often used in foundation plantings and similar situations․
Prune during the dormant period in late winter (January through early March)‚ before the growing season․ Removing deadwood and any crossing branches and twiggy growth will usually encourage flowers‚ but hard spring pruning back to stumps is claimed by some‚ but debated‚ to be unnecessary and counter-productive‚ as it weakens the tree‚ resulting in weak and floppy flowers the following year․
Disease Resistance is Much More Important Than Many People Think
Older varieties of crepe myrtle are susceptible to powdery mildew‚ a white powdery fungus that can coat the leaves during the summer months‚ especially during humid conditions․ And‚ of course‚ if you are gardening anywhere in Louisi
