A tropical perennial herb, hardy and resistant to attack by fungi or insects. It grows wild but now cultivated scientifically for ornamental and medicinal use. Flowers white or deep rose coloured; follicles long. Earlier civilisations knew about its use in medicine.

The plant originated from Malagasy (Madagascar), then spread to Mozambique, followed by several South East Asian countries viz., South Vietnam, Philippines and Australia, including India and Ceylon (Tiwari et al., 2011).