What is Basil?

An herb is a plant whose leaves, seeds, or flowers are used for flavoring food or in medicine. Other uses of herbs include cosmetics, dyes, and perfumes. The name derives from the Latin herba, meaning "green crops." Basil, also known as Sweet Basil, is a member of the Lamiaceae family, which also includes mint, oregano, catnip, rosemary, and sage. Most of the culinary varieties are of the genus Ocimum basilicum, while the related and also popular lemon basil is Ocimum xcitriodorum.

History. The name comes from the Greek word for king, basileus. Basil may have originated in India, but it has since spread to many Asian and Mediterranean countries, as well as Africa and Central and South America, and is cultivated commercially in California. Many traditions about the herb's powers have to do with love and the afterlife.

Description. Ocimum basilicum, sometimes referred to as Mediterranean basil to distinguish it from other varieties, particularly Thai, is noted for its variety. Leaves are varied in size; either thin and elongated or rounded; smooth-edged or serrated; green, purple, or variegated. Flowers may be white or purple in color, and the plant itself can vary from 8 in. to 3 ft. (about 20 to 91 cm) in height.

Ocimum xcitriodorum is a small plant with white flowers, smaller leaves than Ocimum basilicum, and a characteristic lemony fragrance. Other fragrances, such as cinnamon, anise, and licorice, are also available; and other varieties grow in Thailand, India, and Africa. New species are often created.

Gardening. Though perennial in warmer climates, basil is a frost-sensitive annual in much of the United States. It can be planted from seed or rooted from cuttings. Since lemon basil does not seed, propagation by cutting is the only option.

Pruning encourages bushy growth, and basil should be pruned and deadheaded regularly. Some gardeners treat it as an ornamental, as well as a culinary plant. Basil can sometimes be successfully transferred indoors for the winter.

Food and other uses. Fresh Mediterranean basil leaf is a principal component of pesto alla Genovese (green pesto) and also appears in pesto rosso (red pesto), which includes tomatoes as well. The leaf is also used as a seasoning in tomato sauce, pizza, Insalata Caprese, salad dressing, and cooked vegetable dishes. Dried leaf is found in the mixed spice called "Italian seasoning," and sometimes is a component of bouquet garni. Thai basils, which differ from Mediterranean varieties, are used in Thai green curry and as a garnish.

Basil is also used in desserts, including ice cream and sorbet, custard and zabaglione. The seeds are used to thicken the consistency of certain Thai foods. The essential oil is used in perfumes.

Preservation. Basil should be harvested periodically to encourage regrowth, but it is especially important to do a final harvest before the temperature drops, as the plant is not hardy. After harvesting, many gardeners prefer to freeze the herb, rather than dry it, because the flavor and color are better preserved. One can simply strip, clean and freeze the leaves on baking sheets before transferring them to bags.

Alternatively, chop the leaves with olive oil and, if you like, the other pesto Genovese ingredients except the cheese, and freeze in bags. You can also process the leaves with olive oil or a little water and freeze initially in ice cube trays, then transfer them to bags. To dry basil, bind stems of several plants together and hang in a dark, dry place.