The genus name Orthosiphon Benth. was coined from two Latin words, “Iorthos” and “siphon”. The word “Iorthos” referred to straight while “siphon” meant tube-like or cylindrical. These two words actually referred to the upright or straight tube-like flowers that were produced by the Orthosiphon spp. and this was considered as one of the main characteristics of the Lamiaceae family, while “aristatus” means bearded.
Orthosiphon aristatus is a herb or undershrub that can be reach 1–2 m tall and spread to a meter wide. It is erect and highly branched with a tendency to touch the ground and root easily. The leaves are simple, opposite, glabrous to puberulent on both surfaces and lanceolate-shaped with coarsely serrated margins. The inflorescences are thyrsoid and the cymes are sessile, that are 10–20 cm long. The flowers are bisexual, the calyx are zygomorphic, posterior lip rounded, broad, 2 lateral lobes deltoid, 2 anterior lobes subulate and the corolla are zygomorphic, strongly 2-lipped, posterior lip 4-lobed, anterior lip horizontal and concave. The stamens are 4, c. 5–6 cm long, declinate, long-exserted and the stigma are capitate-clavate. The fruit has a mericarp of 4 dry nutlets. Three cultivars of O. aristatus are distinguished: one with bluish-violet and two with white flowers. The white-flowered cultivar with reddish stems, petioles and leaf veins appears to possess the best diuretic qualities.
In Malaysia, the plant called “misai kucing” or “kumis kucing” in Malay, cat’s whiskers or java tea. The species is planted as an attractive ornamental garden plant. It is also popularly used as a traditional and medication herb, especially in Malaysia and Indonesia to treat diabetes, kidney or renal stones and urinary disorders, high blood pressure, rheumatism, arteriosclerosis, nephritis and gout. It is also reportedly effective for anti-fungal and anti-bacterial purposes. Dried leaves can be brewed as a herbal tea or a tasty drink with honey or milk.
The species is widely distributed from India, Indo-China and Thailand, through Malesia to tropical Australia. As a wild plant, it occurs throughout Malesia, but is apparently rare in Borneo, Sulawesi and the Moluccas. It is now grown in South-East Asia, Africa, Georgia and Cuba. In the wild, the plant can be seen growing along forest borders in shaded not too dry localities, along roadsides and ditches, and in teak and bamboo forests, in rubber estates, among sago palms, in grassland, in regrowths and old garden land, from sea level to c. 1000 m altitude. The plants flower throughout the year.
