Oregano ( Origanum vulgare ) is a flowering plant in the famous mint (Lamiaceae). It is native to temporal Western and Southwestern Eurasia and the Mediterranean region. Oregano is a perennial herb, growing from 20–80 cm tall, with opposite leaves 1–4 cm long. The flowers are purple, 3–4 mm long, produced in erect spikes. It is sometimes called wild marjoram, and its close relative, O. majorana, is known as sweet marjoram. Oregano is related to the herb marjoram, sometimes being referred to as wild marjoram. Oregano has purple flowers and spade-shaped, olive-green leaves. It is a perennial, although it is grown as an annual in colder climates, it often does not survive the winter. Oregano is planted in early spring, the plants being spaced 30 cm apart in fairly dry soil, with full sun. Oregano will grow in a pH range between 6.0 (mildly acidic) and 9.0 (strongly alkaline), with a preferred range between 6.0 and 8.0. It prefers a hot, relatively dry climate, but does well in other environments.