Lagerstroemia speciosa Seeds | Queen’s Crape Myrtle
LATIN NAME: Lagerstroemia speciosa
COMMON NAME: Queen’s Crape Myrtle
Plant Profile
Lagerstroemia speciosa is the tree-sized crape myrtle, and it is grown for a mass of pink-purple flowers that open at the top of the crown in early summer. The flowers are crinkled, like crepe paper, in a large panicle, and they are followed by woody capsules that persist through winter. The leaves are large, oval and leathery, and they turn red before they fall.
The species grows in the moist forests of tropical Asia, from India to the Philippines, and it is planted across the tropics as a street tree and as an ornamental. It reaches twenty metres with a broad, rounded crown, and the bark peels in patches, leaving a smooth, mottled surface that is one of the tree’s attractions.
Science & Biotechnology
The leaf contains corosolic acid, a triterpene that has been studied for its effect on blood glucose, and the tree is the source of banaba, a herbal preparation sold for diabetes. The evidence is limited: small trials have shown modest effects, and the products are not standardised, so it is not a substitute for treatment.
The timber is hard, strong and durable, sold as pyinma in Myanmar and as banaba in the Philippines, and it is used for furniture, for flooring and for railway sleepers. The tree is also a host of the lac insect, and the bark is used for tanning. In the Philippines the leaf is also used to wash hair, and the bark is used as a fish poison in some districts, a practice that is now discouraged because it kills everything in the pool.
Uses & Benefits
The tree is grown as an ornamental and as a street tree, and the timber is used for furniture and for construction. The leaf is used to make a tea, both as a folk remedy and as a commercial herbal product, and the root and the bark are used in local medicine.
In Ayurveda the bark and the seed are used for diarrhoea and for stomach complaints, and the leaf is used for diabetes. The tree is planted in parks and along roads for the flowers and the shade, and it is one of the most common street trees of tropical Asia.
Growing from Seed
Seed germinates readily. Sow it at 25 to 30 degrees in spring, and seedlings appear in two to four weeks. Cuttings of half-ripe wood also root, and selected forms are propagated that way.
The tree wants full sun and a deep, moist soil, and it tolerates heat and short drought. It is tender below about zero. It grows fast and can be pruned hard, which is why it is used as a street tree, and it flowers best in full sun with a warm, wet summer. Mulch in spring and water through the first two dry seasons, then leave it.
Our Take
A big crape myrtle for a tropical street or garden, with useful timber and a leaf that has become a diabetes remedy of uncertain value.
Related Reading
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