How dull our summer streetscapes would be without the luscious blossoms of crape myrtles. Be they white, purple, pink or almost red, the plump clusters of blooms set off visual fireworks from April into October.
After the flowers have faded, interest continues, as many members of the Lagerstroemia genus have leaves that turn brilliant hues in autumn. Add to these attributes exfoliating bark that creates tonal patterns on their trunks, and it is easy to understand why crape myrtles are ubiquitous in our region.
Lagerstroemia indica is the species most often seen in New Orleans and surrounding areas. Although it grows as a multitrunked shrub in its natural state, most often it is trained into a single-trunked tree form.
It’s important to remove suckers and growth from the bottom as the tree matures. Little additional care is needed, however, because the plant is hardy to Zone 7, temperatures that are rarely experienced in south Louisiana. On the opposite end of the spectrum, crape myrtles are happy roasting in the sun even when the rest of us are not.
Although crape myrtles are nearly carefree in our environment, some issues are common. Powdery mildew (a fungus) can occur when nights are cool and humid, followed by days that are warm and dry. It coats leaves with a grayish white substance, reduces flowering and causes leaves to deform. Powdery mildew can be controlled with a fungicide.
In prolonged periods of warm, wet days, the cercospora lythracearum fungus can produce spots on the trees’ leaves, which then turn yellow and fall off in midsummer. Although the appearance of a defoliated tree can be alarming, the tree should not suffer in the long run.
Likewise, infestations of aphids can reduce flowering by sucking out the sap from tender new growth. They also produce honeydew that results in sooty mold on the leaves. Aphids can be eliminated by a single application of imitacloprid, an insecticide found in commercially available products.
When choosing a crape myrtle for your home landscape, keep in mind the size the tree will reach at maturity. If you have room for a large crape myrtle (20 to 30 feet tall), your choices include Arapaho (red), Basham’s Party Pink (pale pink to light lavender), Biloxi (light pink), Carolina Beauty (deep red), Miami (dark pink), Natchez (white) and Tuscarora (dark pink) among others.
Medium-sized crape myrtles grow anywhere from 10 to 20 feet tall. Recommended varieties include Catawba (violet purple), Cheyenne (bright red), Choctaw (bright pink), Comanche (coral pink), Osage (clear pink), Seminole (vibrant pink) and Twilight (purple).
Many dwarf and weeping varieties have been introduced and range in size from 1 to 10 feet tall. They include Acoma Semi-dwarf (white), Baton Rouge (red), Chickasaw (purplish pink), New Orleans weeping (purple) and Zuni (violet).
“Crape murder” is a term used widely to refer to the practice of pollarding crape myrtles, or cutting back new growth every year to the same node, thereby forming a pollard head.
The practice has been employed in Europe for hundreds of years to manage the size of trees. Tree experts lament that “crape murder” or pollarding crape myrtles has become fashionable here, for they prize the natural form of the trees.
Their argument is a good one: If you have chosen your crape myrtle well for its location, there will be no need to control its size.
So is pollarding really “crape murder” or simply an alternative pruning method aimed at controlling size and yielding a certain “look”? That is a question for the experts to decide.