Cultivating White Crepe Myrtle: Tips for Growth, Care, and Pruning
A tiger swallowtail enjoys nectar from a white-flowering white crepe myrtle bush.
White crepe myrtle, a renowned tree in U.S. states like Georgia and South Carolina, can also be cultivated in some parts of the North, albeit with lower expectations. The variety you select matters, based on the size, bloom color, and fragrance preferences.
Taxonomy and Botanical Information
The scientific classification of white crepe myrtle is Lagerstroemia x Natchez. This widely grown landscaping tree is a hybrid resulting from crossing L. indica and L. fauriei. Originally from Asia, Lagerstroemia is naturalized in the Southeastern U.S., and Natchez is its cultivar name.
White crepe myrtles are deciduous shrubs or small trees.
Understanding Common Names
The plant’s leaves are similar to those of true myrtles (Myrtus communis), which explains the “myrtle” part of the common name. The “crepe” portion refers to the flower petals’ crinkly texture, which is reminiscent of crepe paper.
USDA Plant Hardiness Zones
White crepe myrtles can be grown in zones as cold as planting zone 6. In the northernmost parts of their range, colder climates keep the plants in shrub form. They are considerably more popular in the South, where they grow more vigorously.
In the North, the plant may put on its best flowering display during unusually hot summers. Some years, it may barely bloom at all. The cold winters may not kill the plant, but little of it will remain alive above ground.
In the South, white crepe myrtles grow as trees and can reach heights of over 30 feet. The foliage turns reddish-orange in autumn. Their reddish-brown bark peels similarly to birch trees (Betula spp.), providing winter interest. These trees produce white blooms.
The flowers are the primary attraction, growing in eye-catching clusters with a display lasting from mid-summer to fall. Butterflies are drawn to the flowers, which yield brownish fruits that persist through winter.
Avoid over-fertilizing white crepe myrtles, as excessive fertilization can diminish blooming and increase leaf growth. This can result in winter injury and reduced visual appeal. Brown leaves are a common issue, with various potential causes.
Sun and Soil Requirements
White crepe myrtle prefers full sun and well-drained soil. Full sun exposure can help prevent disease in less mildew-resistant varieties. Soil pH should range between 5.0 and 6.5.
These plants make excellent specimens and, when grouped, can create decorative borders or privacy hedges. They are often used for street plantings in the South due to their adaptability to confined spaces.
Numerous crepe myrtle cultivars have been developed and marketed, including:
- Bicolor (pink; dwarf form, 2-4 feet)
- Cherokee (red; 10 feet)
- Acoma (white; 15 feet)
- Seminole (pink; 17 feet)
- Tuscarora (coral pink; 23 feet)
- Choctaw (pink; 27 feet)
Lagerstroemia fauriei, the parent of the Natchez variety, is a 10-foot shrub that grows in zones 6 to 9. This type of crepe myrtle is unique for its fragrant flowers and strong resistance to powdery mildew.
Disease and Pruning
White crepe myrtles, like L. fauriei, are highly resistant to mildew. Pruning branches that cross over others can promote airflow and reduce susceptibility to mildew. Aphids can also be an issue, as their honeydew drops can create a mess on plants, cars, decks, and patios.
These trees often produce multiple main stems. Some people severely prune crepe myrtle trees in winter to restrict growth to one main stem, but this can damage their appearance. Instead, opt for dwarf varieties or limit pruning to thinning for better airflow. Prune in early spring, as these shrubs bloom on new wood.
Remove spent flower heads throughout summer (deadheading) to encourage continuous blooming. Remove any suckers that appear. Volunteer seedlings may also sprout in your lawn, which can be a nuisance or an opportunity for transplanting.
By following these care, pruning, and growth tips, you’ll be able to cultivate and maintain a healthy and beautiful white crepe myrtle tree that thrives in your landscape.