Oregano; scientific name Origanum vulgare) is a common species of Origanum, agenus of the mint family (Lamiaceae). It is native to temperate western and southwestern Eurasia and the Mediterranean region.
Oregano is a perennial herb, growing from 20–80 cm (7.9–31.5 in) tall, with opposite leaves 1–4 cm (0.39–1.57 in) long. 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. The flowers are purple, 3–4 mm (0.12–0.16 in) long, produced in erect spikes. It is sometimes called wild marjoram, and its close relative O. majorana is known as sweet marjoram.
Oregano is the anglicised form of the Italian word origano, or possibly of the medieval Latin organum; this latter is used in at least one Old English work. Both were drawn from the Classical Latin term origanum, which probably referred specifically to sweet marjoram, and was itself a derivation from the Greek (origanon), which simply referred to “an acrid herb”. The etymology of the Greek term is often given as oros “mountain” + ganos “brightness”.
Description and biology
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, as it often does not survive the winter. Oregano is planted in early spring, the plants being spaced 30 cm (12 in) apart in fairly dry soil, with full sun. It prefers a hot, relatively dry climate, but does well in other environments.
Many subspecies and strains of oregano have been developed by humans over centuries for their unique flavours or other characteristics. Tastes range from spicy or astringent to more complicated and sweet. Simple oregano sold in garden stores as Origanum vulgare may have a bland taste and larger, less-dense leaves, and is not considered the best for culinary use, with a taste less remarkable and pungent. It can pollinate other more sophisticated strains, but the offspring are rarely better in quality.
The related species, Origanum onites (Greece, Turkey) and O. syriacum (West Asia), have similar flavors. A closely related plant ismarjoram from Turkey, which differs significantly in taste though, because phenolic compounds are missing from its essential oil. Some varieties show a flavor intermediate between oregano and marjoram.
Oregano is an important culinary herb, used for the flavor of its leaves, which can be more flavorful when dried than fresh. It has an aromatic, warm, and slightly bitter taste, which can vary in intensity. Good-quality oregano may be strong enough almost to numb the tongue, but cultivars adapted to colder climates often have a lesser flavor. Factors such as climate, season, and soil composition may affect the aromatic oils present, and this effect may be greater than the differences between the various species of plants. Among the chemical compounds contributing to the flavour are carvacrol, thymol, limonene, pinene, ocimene, and caryophyllene.
Oregano’s most prominent modern use is as the staple herb of Italian-American cuisine. Its popularity in the U.S. began when soldiers returning from World War II brought back with them a taste for the “pizza herb”, which had probably been eaten in southern Italy for centuries. There, it is most frequently used with roasted, fried, or grilled vegetables, meat, and fish. Oregano combines well with spicy foods popular in southern Italy. It is less commonly used in the north of the country, as marjoram generally is preferred.
The herb is widely used in cuisines of the Mediterranean Basin, the Philippines, and Latin America.
In Turkish cuisine, oregano is mostly used for flavoring meat, especially for mutton and lamb. In barbecue and kebabrestaurants, it can be usually found as a condiment, together with paprika, salt, and pepper.
The dried and ground leaves are most often used in Greece to add flavor to Greek salad, and is usually added to the lemon-olive oil sauce that accompanies fish or meat grills and casseroles.
Oregano is used in the southern Philippines to eliminate the odor of carabao or water buffalo when boiling it, while simultaneously imparting flavor.