Oregano and marjoram are often confused; both oregano and marjoram belong to the same plant family and, to add to the confusion, oregano is also known as marjoram.
The common herb oregano (Origanum vulgare) belongs to the plant family Lamiaceae, as does the herb sweet marjoram (Origanum marjorana); however, both herbs are often confused with each other. Oregano is alternatively known by the synonym wild marjoram, indicating the importance of identifying a plant by its Latin name or through the plant classification system.
Description of Oregano and Marjoram
Oregano is a hardy, bushy perennial plant which has purple, hairy stems, oval leaves and pink-purple flowers; sweet marjoram is also a bushy perennial plant but is not as hardy as oregano. Sweet marjoram may be cultivated as an annual in colder climes; it has oval leaves, a hairy stem and small gray-white flowers which grow in clusters. Both herbs are very aromatic.
Distribution of Marjoram and Oregano
Oregano grows wild (hence its name wild marjoram) in Europe, central Asia and the Mediterranean region; in the Mediterranean, it is known as oregano rather than wild marjoram but should not be confused further with Spanish marjoram (Thymus mastichina) or Spanish oregano (Thymus capitatus). Sweet marjoram is native to Egypt, North Africa and the Mediterranean region.
Early Historical Use of Marjoram and Oregano
Early herbalists used both herbs, oregano and marjoram, for their powerful antiseptic properties. In China, oregano has been used to treat fever, itchy skin, diarrhea and vomiting; sweet marjoram is a more gentle herb, and has traditionally been used both as a folk remedy and as a culinary herb. It is known for its soothing and warming properties and has been used to treat respiratory problems, nervous tension, menstrual and digestive difficulties.
Sweet Marjoram Essential Oil
Sweet marjoram produces an essential oil which is used in aromatherapy; it is analgesic, antiseptic,anti-viral, carminative, sedative, laxative, bactericidal and a tonic. The essential oil of sweet marjoram is used to treat arthritis, rheumatism, asthma, bronchitis, constipation, headaches, migraines, insomnia, PMT, flatulence and stress and nervous tension; it should not be used in pregnancy.
Oregano Essential Oil
Oregano also produces an essential oil but it is not commonly used in aromatherapy; the essential oil of oregano should not be used during pregnancy and it is a skin irritant and dermal toxin, making it unsafe to use in direct skin contact. It is more common for Spanish oregano (Thymus capitatus) to be sold as ‘oregano’ oil, although it too has little use in aromatherapy due to its actions as a skin and dermal irritant.
Marjoram and Oregano Species
The botanical classification of the marjoram and oregano species is very confusing; some species are produce essential oils too. There are over thirty varieties including, in addition to those already mentioned:
Greek marjoram (Origanum heracleoticum)
Mexican oregano (Lippia graveolens)
Syrian oregano (Origanum maru)
French or pot marjoram (Origanum/Marjorana onites).