One of my biggest pet peeves in driving around the Shoals of NW Alabama is improper pruning of crepe myrtle trees. Crepe Myrtles are trees that many owners treat as shrubs. It is the most planted tree in the US and is available in white, purple or lilac, red and pink colors.
With the large number planted, many home owners as well as lawn services improperly prune them so that they form a Medusa head when new growth starts. Some are so drastically cut back, using a technique called Crepe murder or castration; it’s amazing that they grace the owner with growth. It’s like the pruner has turned into Barney Fife around a moonshine still with a great big axe. The growth that does result is a scantily clad shrub. It takes the crepe myrtle half of the summer to recoup, while the properly pruned one is in full bloom. The Medusa form of pruning results in a short pom pom growth. A properly pruned tree will flower sooner that one that has been castrated. One of the worse cases of castration I’ve notices has been at Tuscumbia Utilities in my home town. Are you a Crepe myrtle murderer? Don’t go Lizzie Borden on your crepe myrtles.
If you have one that has the Medusa heads, cut off the medusa heads and allow one or two branches to come back out in the spring. It may mean pinching off several times during the year to prevent the Medusa heads from reforming. Extremely large trunks with Medusa heads may mean just starting over and trimming the tree down to the ground and allow two or three nice branches to come back out.
Another issue is planting a large crepe myrtle tree close to the building. A crepe myrtle is a tree. The result when the tree gets too large is crepe murder to control its size. There are various sizes of crepe myrtles available. Dwarf (3-5 feet) varieties include Centennial, purple in color, Victor a dark red, and Ozark Spring a lavender. Some semi dwarf (5-10 ft) varieties are Acoma a white variety, pinks Caddo, Hopi, Pecos and Prairie Lace; Zuni a lavender, Tonto a red. My favorite color are the reds.
The prettiest presentation of crepe myrtle in trimming it in a tree form choosing 2 or 3 main trunks and cutting off all growth up the trunk for several feet and exposing the beautiful bark of the crepe myrtle. If you must prune, only trim any branches or limbs a pencil width or less in size and the seed heads. Stand and look at the tree, then walk around it looking at it like it is a painting. Before just lopping, take a good look at your tree and decide which of the limbs need to remain in your painting, and trim the rest.
Diseases such as powdery mildew, black spot, sooty mold, tip blight, leaf spot, and root rot can be prevented by planting crepe myrtles in full sun with good air circulation.