Oregano is a shrub-like herb that grows upright or in a creeping manner, depending on the variety. It is native to the Mediterranean basin at the crossroads of Europe, Africa, and Asia. Origanum is its genus name; in Greek, that means, “joy of the mountain.” Oregano thrives in a mountain habitat of dry, rocky, calcareous soil formed from the decaying shells and bones of sea creatures. The hotter and dryer the climate, the stronger the herb’s aroma and flavor will be. It will also develop a bountiful display of striking tubular flowers. Oregano has the strongest flavor profile of any Mediterranean herb. Several species have become naturalized in North America.
From Magic to Medicine
The mythological Greek goddess Aphrodite created spicy, pungent oregano to signify joy, and she planted it in her garden on Mt. Olympus. It was Greece’s herb of happiness, used in love potions and marriage rituals. Oregano’s close relative marjoram is associated with the corresponding Roman goddess, Venus, who cast a magic spell to give the herb a pleasing sweet scent.
Early evidence of oregano was found on 4,000-year-old stone tablets from ancient Anatolia. Greek physician Hippocrates prescribed oregano to relieve gastrointestinal distress and to protect against respiratory ailments. Hot oregano tea with honey cured asthma and colds. The Greco-Roman culture also embraced oregano as a food, which provided antioxidants and other health-giving benefits.
Origanum plants have been used as natural medicines since antiquity. Ongoing scientific studies and rich historical evidence strongly support many traditional uses. Active compounds in their essential oils are known to possess antiviral, antifungal, and antimicrobial properties. Purdue University scientists recently announced research on an anti-cancer compound in oregano and thyme that can suppress tumor development.
Origanum Spells Confusion!
The genus Origanum belongs to the Lamiaceae, or mint, family with 57 accepted species and nine subspecies. Extensive hybridization occurs between the species, and many plants have multiple common names and synonyms, which are alternative scientific names.
Oregano (Origanum vulgare) and marjoram (Origanum majorana) are closely related. Similar in appearance, their histories are deeply entwined, and sometimes it’s difficult to differentiate between the two. To further complicate matters, plants from entirely different families are called oregano and have similar flavor profiles.
This can be confusing for botanists, commercial growers, gardeners, and cooks. One garden writer laments that the task of sorting them out is a “deeply tangled taxonomic thicket.” Oregano and marjoram are culinary twins with a noteworthy difference — one is robust and feisty; the other is mild-mannered and sweet.
A word on marjoram: introduced to 16th century England, sweet marjoram became associated with the English cottage garden. It was widely grown as a potherb in Colonial America. Thomas Jefferson requested it for his garden in 1794. Oregano isn’t listed in the 1943 printing of The Joy of Cooking, but marjoram is. The sweet herb was commonly included in American cookbooks until after World War II, when service members returned from the Mediterranean with an appetite for oregano and pizza. Oregano became everyone’s favorite herb, supplanting marjoram and sage — another Colonial favorite.
O. vulgare is the wild Mediterranean herb; its species epithet vulgare means “common.” It’s called oregano in the United States but wild marjoram in Britain. The flavor isn’t as nuanced as Greek oregano. The creeping rootstock is invasive. Eye-catching pink flowers attract insect pollinators and dry well for lasting floral arrangements. The dried commercial herb may be blended with Turkish or Mexican oregano or marjoram. Herb expert Dr. Arthur O. Tucker advises, “Think of oregano as a flavor rather than a genus or species.”
O. Vulgare subsp. hirtum (synonym O. heracleoticum) is the true Greek oregano — the kind that gives special savor to pizza and spaghetti sauces. It’s essential in Greek and Italian cuisines. The high amount of essential oil contains carvacrol, a creosote-scented phenol that is a main flavor component in oregano. The fresh herb’s intense flavor requires restraint in the kitchen; too much can overpower a dish. Not as invasive as mint, it produces white flowers; its oil is a natural insect repellent.
Origanum x majoricum (Sicilian oregano or hardy sweet marjoram) is a hybrid of oregano (O. vulgare) and sweet marjoram (O. majorana). It can overwinter in the Midlands in sunny, well-drained soil; seeds may germinate in sandy soil. The appealing aroma and mildly spicy bite will enhance any dish. One of the few oregano scents used by perfumers, it offers hints of warm cardamom and nutmeg.
O. onites, also called rigani (Greek), pot marjoram, or Cretan oregano, is abundant in the Greek islands, especially Crete. It grows beautifully in terra cotta pots, even indoors. A high, essential oil content gives the herb a bright, strong flavor; it is tasty even when flower heads form. Butterflies love it too. Use in Greek, Turkish, and Italian cuisines. McCormick Spices imports Turkish and Mexican oreganos.
O. syriacum (O. maru or Egyptian marjoram) is an herb that’s called za’atar in areas of the Middle East with a taste like an oregano, marjoram, and thyme blend. Syrian oregano is a key ingredient in the Arabic seasoning also called za’atar. Scholars believe this is the biblical “hyssop” mentioned in the Old Testament. Add to soft cheese, salads, yogurt, flatbread, popcorn, herbal tea, and spice pastes for roasted meat and poultry.
Lippia graveolens is Mexican oregano or red brush lippie from the Verbenaceae family with lemon verbena. The herb offers citrus and floral notes; the oregano-like aroma has licorice undertones. Rich in flavonoids, it grows in Mexico and the American Southwest. It’s added to earthy chili powder seasoning for Mexican and Tex-Mex dishes. Blend equal parts dried Mexican oregano, paprika, garlic powder, and ground cumin; add heat with cayenne.
Hot & Spicy
O. vulgare ‘Hot & Spicy’ is bred to be extra spicy. Add to Mexican foods and other robust dishes. Use half the amount of this oregano unless you prefer a chile-hot flavor.
Dittany of Crete
O. dictamnus, or hop marjoram, has soft, down-covered leaves and loves to grow in rock gardens and hanging baskets. The ancient herb is known to have important medical properties; Aristotle was a fan. It’s also used for flavoring vermouth. The herb grows well in the Midlands and is best harvested just before flowering. The leaves have a mild oregano flavor; use for cooking or for a restorative tea.
O. majorana (knotted marjoram) is the tender, perfumed species that is true marjoram. Indigenous to Cypress and Turkey, the herb is cultivated worldwide. It shines in the French Herbes de Provence. Sweet marjoram has delicate, citrusy notes that complement fish, venison, German sausage, and vegetables such as green beans, mushrooms, and winter squash, fresh pasta, egg dishes, peaches, and custards. It grows as an annual in the Midlands.
Birds of a Feather …
Plants flock together too! Origanum herbs make good companion plants. Beware of invasive ones (O. vulgare) that crowd out their orderly neighbors; continuous snipping controls growth. Tall herbs make an attractive backdrop for low-sprawling varieties. Ornamental herbs grace gardens and flower bouquets, but some taste bland so offer little culinary value. Origanums love sun; their aromas and flavors weaken if the soil is too rich and moist.
Purchase plants from reliable sources. Propagate by root divisions from robustly flavored plants. Stems can be rooted in water or moist potting soil. A great deal of variation can be found in the aroma and flavor of different species, varieties, and cultivars; let your nose be your guide. Rub a leaf between your fingers, then decide if the scent appeals to you. Taste it if you can.
Dried or freeze-dried oregano and marjoram are more aromatic with deeper flavors. They stand up well to long cooking. Americans tend to be spice and herb hoarders. For optimum flavor, replace dried herbs after two years, sooner if their aroma and flavor disappear. A lasting relationship with culinary herbs does not mean squirreling away a 10-year-old supply.