Lagerstroemia indica (Crape Myrtle)


Michael's Opinion

“The ornamental bark looks especially beautiful in combination with a contrasting-coloured ground cover. The showy summer flowers, good autumn foliage colour, beautiful trunk coloration, and overall form endow this plant with a four-season appeal and worthy of a specimen tree status.” -Alex X. Niemiera, Professor, School of Plant and Environmental Sciences, Virginia Tech.

Botanical Information

FamilyLythraceae
GenusLagerstroemia
Speciesindica
CategoryWoody
TypeShrub (deciduous)
ReferencesDirr, M. A. (2009). Manual of woody landscape plants: Their identification, ornamental characteristics, culture, propagation and uses (6th ed.). Champaign, IL: Stipes. Wang, X., Chen, J., Zeng, H., Qiao, Z., Li, Y., Cai, N., & Wang, X. (2014). Lagerstroemia indica ‘Xiangyun’, a Seedless Crape Myrtle, HortScience horts, 49(12), 1590-1592. Retrieved Nov 13, 2021, from https://journals.ashs.org/hortsci/view/journals/hortsci/49/12/article-p1590.xml
OriginOriginated in the Himalayas of China, Japan, and Southeast Asia. It was introduced in 1747 and has now become naturalized in the United States of America from Virginia to Arkansas, Texas and Florida.
Ethnobotanical Uses
Disclaimer
Traditional uses of Lagerstroemia indica include tea making of the leaves to aid in the treatment of diabetes. Fresh leaves are used to make a tincture to treat fresh wounds and the leaves are also used as a diuretic and purgative. In the present day, the shrub is used purely as a specimen.

Details

USDA Hardiness Zone6b - 9
USDA Hardiness Ref.
Canadian Hardiness Zone6a
Canada Hardiness Ref.
RHS Hardiness ZoneH6 - H4
RHS Hardiness Ref.
Temperature (°C)-18 - 12C
Temperature (°F)0 - 10
Height5 - 8 m
Spread2 - 8 m
Flowering PeriodJuly, August, September

Description and Growing Information

General DescriptionLagerstroemia indica is an upright, multi-steamed, large deciduous shrub with a vase-shaped growth pattern. - Emily Harvey
ID CharacteristicThis shrub is upright vase-shaped, with elliptic to oblong-shaped leaves with short petioles. It has large flower panicles and smooth exfoliating bark in varying shades of greys and browns.
ShapeUpright, multi-stemmed, wide-spreading with vase-shaped growth pattern.
LandscapeIt is used as a specimen shrub and used in small group planting. Lagerstroemia indica is also used as an understory shrub under larger trees on the edges of forests. The smaller cultivars are used in mass planting, then pruned to create hedges.
PropagationPropagate by seed, soft wood cuttings and semi-hardwood cuttings. To propagate by seed, collect seed capsules as they are dehiscing in autumn, or until the seeds can be shaken free from the capsule. Dry at room temperature and place on paper until fully dry. Then place seeds in a container with well-moistened soil, with germination occurring in three to four weeks. Propagation taken by softwood and semi-hardwood cuttings should be taken in May, June, and July. Application of potassium salt indole-3-butyric acid for forty seconds is recommended but not required. Then placed into moist soil with rooting taking place in three to four weeks. Hardwood cuttings should be taken from October to April. The cutting should be taken with the heel of the older wood attached at the base of the stem, with ample food storage to support the cutting through the rooting process. Application of potassium salt indole-3-butyric acid for forty seconds is recommended but not required. Place the cutting in moist substrate until rooting takes place at roughly three weeks to four weeks.
CultivationThis shrub prefers well-draining, moist sandy to clay soils that have slightly acidic soil ranging from 5-6 pH. It prefers full sun to partial shade, is drought and frost tolerant even when young, and it can even tolerate street planting. It is a fast-growing shrub and pruning should be performed to encourage flowering as well as to control growth. It can be cut back to keep a shrub shape or trained into a small tree; it should be pruned when dormant back to stubs if you are looking for the shrub shape. It is prone to suckering, the suckers should be promptly removed at the base.
PestsIt suffers from quite a few ailments including, powdery mildew, Japanese beetle, black spot, tip blight, sooty mold, root rot, leaf spot, Botryosphaeria canker, Asian ambrosia beetle, aphids and Florida wax scale.
Notable SpecimensThe Norfolk Botanical Garden in Norfolk, Virginia, United States of America has approximately two hundred and fifty different species and cultivars in the Lagerstroemia genus including Lagerstroemia indica.
HabitatLagerstroemia indica is naturally found growing in open grasslands as well as along the forest margins at low altitudes.
Bark/Stem DescriptionThe bark is smooth, grey, and exfoliating which exposes the varied colours of the under-bark. The under-bark ranges in multiple shades of greys and browns.
Flower/Leaf Bud DescriptionSmall, solitary, sessile, oblong, with a slight elbow at the base of the bud. It is closely appressed along the stem, with two acute ciliate scales.
Leaf DescriptionThe leaves are 8 cm long, simple, elliptic to oblong shape with an extremely short petiole with a sessile at the base. It has an acute apex with a rounded base. The top of the leaf is glabrous and has a pilose on the midrib on the underside of the leaf, and margins that are entire. The leaf emerges from the bud a light green with a yellow to red tint, maturing into a dark green. In the autumn the leaves turn to yellow, orange, or red shades before falling to the ground.
Flower DescriptionThe flowers experience a long bloom period, lasting from July into September. The terminal flower panicle is large measuring, 15-20 cm tall: and 8-13 cm wide. Each panicle displays multiple crateriform, crinkled, six-petaled flowers 3 cm in diameter. The flowers display a range of colours from red to rose colour, the cultivars varying from purple, white, pink, mauve, and lavender.
Fruit DescriptionA broad spherical ellipsoidal, six valved dehiscent capsules containing small, winged seeds. It is dark brown in colour and 1 cm in diameter. The capsule stays on the branch of the shrub throughout winter.
Colour DescriptionThe flowers display a range of colours from red to rose colours, the cultivars varying from purple, white, pink, mauve, and lavender. The leaves upon emerging display a light green colour with hints of yellow to red tint, then maturing into a deep green. During the autumn the leaves turn to vivid colours of yellow, orange, and red. The exfoliating bark ranges in different colours of grey on the outer bark and browns on the inner bark. The seed capsule is a dark brown in colour.
Texture DescriptionIt has a medium texture throughout all seasons.

Photographs