Taxonomy
Many subspecies and strains of oregano have been developed by humans over centuries for their unique flavors 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 uses, 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. heracleoticum (Italy, Balkan peninsula, West Asia), have similar flavors. A closely related plant is marjoram from Turkey, which, however, differs significantly in taste, because phenolic compounds are missing from its essential oil. Some varieties show a flavor intermediate between oregano and marjoram.
Notable subspecies are:
- Origanum vulgare gracile (= O. tyttanthum) is originally from Kyrgyzstan, and has glossy green leaves and pink flowers. It grows well in pots or containers, and is more often grown for added ornamental value than other oregano. The flavor is pungent and spicy.
- Origanum vulgare hirtum (Italian oregano, Greek oregano) is a common source of cultivars with a different aroma from those of O. v. gracile. Growth is vigorous and very hardy, with darker green, slightly hairy foliage. Generally, it is considered the best all-purpose culinary subspecies.
- Origanum vulgare onites (Cretan oregano, Turkish oregano, rigani, pot marjoram) is a tender perennial growing to 18 inches tall, with pale green to gray-green woolly rounded foliage. It has a strong, intensely spicy flavor.
- Origanum vulgare syriacum (= O. maru, Syrian oregano, Lebanese oregano, za'atar) has larger leaves that vary in colors ranging from pale green to grayish. Their taste is pungent and similar to Greek oregano.
Example cultivars are:
- Aureum – Golden foliage (greener if grown in shade), mild taste
- Greek Kaliteri – O. v. hirtum strains/landraces, small, hardy, dark, compact, thick, silvery-haired leaves, usually with purple undersides, excellent reputation for flavor and pungency, as well as medicinal uses, strong, archetypal oregano flavor (Greek kaliteri: the best).
- Hot & Spicy – O. v. hirtum strain
- Nana – dwarf cultivar
Cultivars traded as Italian, Sicilian, etc. are usually hardy sweet marjoram (O. ×majoricum), a hybrid between the southern Adriatic O. v. hirtum and sweet majoram (O. majorana). They have a reputation for sweet and spicy tones, with little bitterness, and are prized for their flavor and compatibility with various recipes and sauces.
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