A Basil Harvest

Enlarge Image Image Gallery Polenta with Anise Basil Tomato Sauce (recipe on page 38) stars portabella mushrooms, Parmesan cheese, and good things from the ­garden.

BASILS ARE THE ESSENCE of the summer herb garden and culinary icons with a large and devoted following. These beautiful herbs, which belong to the genus Ocimum, display surprising aromatic subtleties due to their ability to hybridize across species lines, resulting in an almost infinite variety of aromas and tastes. The gene pool creates a plethora of clear, gemlike scents that range through lemon, camphor, cinnamon, clove, and anise. It is this diversity of aromas that both cooks and gardeners find so appealing. Like other herbs, basils are little chemical factories, producing aromatic essential oils that are contained in microscopic sacs on the leaves and stems. When a plant is brushed or chewed, the sacs are ruptured and the fragrance released.

The genus name, Ocimum, comes, appropriately, from the Greek word okimon, meaning “smell”. There are 30 to 150 basil species, depending on who’s counting, and numerous cultivated varieties. The species name of the most common culinary basils, basilicum, is the Latin translation of a Greek word meaning “king”. Basils are members of the mint family (Lamiaceae), a large amalgam of plants characterized by square stems and opposite leaves. Many are aromatic; thyme, oregano, rosemary, and lavender are other familiar herbs in the same family. A few basils are perennial in their native tropical habitats, but most are annuals, which die after flowering and setting fruits.

The genus Ocimum is like a huge extended family, filled with doting parents, favorite aunts and uncles, even the occasional oddball cousin. Your taste will determine what kind of basils you like to grow—spicy, minty, citrus, sweet, pungent, take your pick—and how much you use. Here are some general guidelines to help you get the most from your plants, preserve your harvest, and use it in the kitchen.

Growing

Basils’ cultivation needs are few but important. The semitropical and tropical regions to which Ocimum species are native offer some obvious clues: warm, sunny weather and plenty of moisture. Basils do well where hot-weather vegetables such as tomatoes, peppers, and eggplants flourish; their finest growth occurs during periods when night temperatures are above 60°F. In most areas of the United States, basils thus have a limited period of rapid growth. In the mid-Atlantic states, where we live, they grow well for about 140 days, beginning in late May or early June and ending in October.

Basils grow best in a site with daylong sun, but most varieties can subsist on as little as three to four hours of direct sunlight. They will tolerate a wide range of soil conditions but will grow best in a well-drained, loamy, nearly neutral soil (pH 6 to 6.5) that is well endowed with nutrients. Good air circulation discourages fungus diseases.

Most basil species can be ­propagated from seed. (Certain cultivars are so unstable that they must be grown from stem cuttings; purple-leaved types are notoriously difficult for breeders to tame.) Seeds may be sown directly into the garden after the frost-free date, or they may be started indoors four to six weeks earlier, which gives the gardener a head start and permits additional harvests. Space transplants or thin seedlings to 12 to 18 inches apart.