Lagerstroemia

Crape myrtle is a genus of 49 species and many cultivars of perennial, deciduous and evergreen shrubs or small trees with showy summer to fall blooms in the Loosestrife family. These species and cultivars vary in height (from 3 feet to more than 20), flower color, growth habit, and bloom season. Most cultivars are hybrids (the most common being a cross of Common Crape Myrtle with Japanese Crape Myrtle). The genus is named after the 18th century Swedish botanist Magnus von Lagerstroem who directed the Swedish East India Company and was a friend of Linnaeus. The common name refers to the crepe-papery inflorescences and the myrtle-like (Myrtus communis) features of the bark and foliage.

Crape myrtle does best in full sun and average medium moisture, well drained soil. The plant will tolerate loamy, clay soils with good drainage, but overly fertile soils tend to produce lush foliage at the expense of flowering. Water roots deeply, particularly in dry spells, but avoid wetting the foliage. Crape myrtle tends to do well in warm, Southern climates, but it may be wise to plant in a protected location and apply a winter mulch. If the plant fails, it is usually due to the lack of summer heat to encourage vigorous growth and harden the wood.

Crape myrtle, in general, are tough and cold hardy. In warmer areas many can be grown as trees, but in colder climates they may be killed to the ground and resprout to be grown more as shrubs. The plant can be hard pruned, but such pruning tends to produce poor form, fewer flowers, and poorly attached stems and shoots that tend to break off. If pruning is needed, it is best to do it by late summer to enable new growth to establish itself before winter.

The Clemson Cooperative Extension Home & Garden Information Center has a factsheet on common pests and diseases.

Insects, Diseases, and Other Plant Problems:  Aphids and scale are occasional insect pests.  Powdery mildew and fungal leaf spot are common disease problems. Bark scale can infest bark, twigs, and leaves, but infected limbs can be removed to control the pest. If planted in alkaline soils, the leaves will show chlorosis (yellowing). Winter injury, particularly to top growth, may occur in USDA Zones 5 and 6.