(L.) Roth
Description
Ipomoea purpurea, the common morning glory, is a neotropical species of Mexican and Central American origin now thoroughly naturalised worldwide; GBIF records exceed 36,000 occurrences spanning the Americas (US, MX, BR, EC, PE, AR, BO, CO), Europe, southern Africa, eastern Asia and Australia. In the Himalaya it persists as an escaped ornamental and weed of disturbed ground, hedgerows, field margins and roadsides. The plants noted at Barron Chatti in Garhwal at 2300 m in June and along the Mo-Chu in Bhutan at 1550 m in October illustrate its tolerance of a broad warm-temperate to subtropical elevation range and its long, monsoon-spanning flowering season.
It is an annual twining herb with slender, retrorsely hairy stems climbing by means of left-handed coiling. The leaves are alternate, long-petiolate, broadly ovate-cordate and usually entire, acuminate at the apex with a deep basal sinus. Flowers arise in axillary cymes of one to several; each has a hairy, lanceolate-lobed calyx and a showy funnelform corolla 4 to 6 cm across, varying from purple and violet-blue to pink, magenta and white, with a paler throat and five faint interplical bands. The five stamens are unequal and included; the superior ovary ripens into a globose, three-locular capsule releasing several glabrous, dark trigonous seeds.
The species is taxonomically straightforward within Ipomoea but horticulturally polymorphic, with numerous colour cultivars. Its self-compatible, bee-pollinated flowers and prolific hard-coated seed make it a successful colonist and, in warm regions, an agricultural weed. It is of no conservation concern; rather, its capacity to naturalise warrants monitoring in ruderal habitats.
Author: (L.) Roth · Sources: POWO (Kew), GBIF, Flora of China Vol. 16, Flora of Bhutan Vol. 2, Flora of Pakistan, A Monograph of the Convolvulaceae (Ipomoea)