Clove basil

Clove basil (Ocimum gratissimum) is an aromatic herb or small shrub of the mint family (Lamiaceae), 0.5–2 m tall, with square, branching, finely hairy stems. The leaves are opposite, ovate to lanceolate, 5–13 cm long, with shallowly toothed margins and hairs on both surfaces; when crushed they release a strong clove-like scent. The small white or creamy-white flowers are borne in branched terminal clusters; the calyx and corolla are two-lipped, typical of the mint family, and are insect-pollinated. The fruit is a small nutlet with dark-brown seeds. The whole plant yields a fragrant essential oil whose main component is eugenol.

Clove basil is native to India and tropical Africa and is widely cultivated across South and Southeast Asia and other tropical regions. In Vietnam it grows wild and is planted around homes, commonly called white hương nhu (Ocimum gratissimum) to distinguish it from purple hương nhu (Ocimum tenuiflorum). The plant is widely used in traditional and folk medicine: the leaves and young shoots are boiled for steam baths to relieve colds, fever and headache; a decoction is taken for coughs, stomach ache and diarrhoea; the leaves are also used as a spice. The essential oil, rich in eugenol and thymol, is antibacterial, antifungal and anti-inflammatory and is used in fragrances and cosmetics.