Oregano is a flowering plant in the mint family (Lamiaceae). It is native to temperate Western and Southwestern Eurasia and the Mediterranean region. Oregano is a perennial herb, growing from 20â80 cm (8â31 in) tall, with opposite leaves 1â4 cm (1â2â1+1â2 in) long. The flowers are purple, 3â4 mm (1â8â3â16 in) long, produced in erect spikes. It is sometimes called wild marjoram, and its close relative, O. majorana, is known as sweet marjoram.