Thomas J. Story
Basil smells like summer. Take a deep whiff of its distinctive spicy-sweet scent and you can almost taste the juicy tomato slices waiting on your plate for a few flavor-filled leaves. No wonder basil is among our favorite annual herbs.
The essential oils that give sweet basil leaves their aroma are made of just a few compounds. Linalool is responsible for the light floral character; eugenol, the clove; and methyl chavicol, the anise.
But the ratio of these compounds is different in each type of basil, and consequently so is each variety's perfume. If you grow several kinds of basil, you can select whatever scent complements the food you're preparing.
Use standard sweet basils―the type most commonly stocked at supermarkets―for pesto or other Italian dishes; lemon basils with fish or poultry; anise basil for Thai or other spicy dishes; and red and purple basils for garnish or to add sparkle to salads.
But don't restrict yourself; experiment by growing several varieties to familiarize yourself with their fragrances and flavors. Plant basil soon for a summer harvest.
Six tasty basils
Sweet. A generic term for classic culinary basil. Large, smooth green leaves; white flowers. Scent combines mint, spice, citrus, and anise. 'Genovese', shown here, is a favorite for pesto.
Anise. Also known as licorice or Thai basil. 'Siam Queen' is shown here. Green leaves; purple flowers and stems. Both leaves and flowers have spicy anise scent.
Cinnamon. Pointed green leaves; reddish stems; lavender flowers. Strong cinnamon scent.
Lemon. Small light green leaves; white flowers. Sweet lemon scent plus traces of mint and spice. 'Sweet Dani', shown here, is the best-known variety; 'Mrs. Burns' has bigger leaves, stronger scent.
Purple-leafed. Burgundy- to plum-colored foliage; white to lavender flowers with dark bracts. Mild to peppery taste depending on variety. 'Red Rubin' is shown here. 'Dark Opal' and 'Purple Ruffles' are two other common varieties.
Bush. Also known as Greek or dwarf basil. Tiny leaves on 1-foot-tall plants; white flowers. Stems are soft and succulent, so you can chop up entire sprig, stem and all. Flavor and fragrance vary but tend to be spicy.
Planting and care
One strategy for making the most of the short basil season is to establish a quick crop by starting with seedlings; most nurseries carry at least a half-dozen varieties.
Wait until nighttime temperatures remain above 55° to plant seedlings or sow seeds directly in the ground. If you want to get a head start, sow seeds indoors four to six weeks before setting out.
Plant in a location that provides at least six hours of direct sun. (In hot locations, light afternoon shade is preferable.) Soil should be neutral (6 to 6.5 pH), rich, and well drained. Space plants 10 to 12 inches apart; seeds about 1 inch apart.
Water. Give plants about 1 inch of water per week. Feed with fish emulsion or a balanced fertilizer when you transplant, then fertilize once or twice during the growing season, such as after a heavy harvest.
Check for pests. Slugs and snails love basil. Encircle young seedlings with a barrier of copper flashing to deter pests.
Harvest generously and frequently. Basil tastes better before it flowers, and it will start flowering after producing about six pairs of leaves. Snip off growing tips often. Cut whole stems. When plants start to get ahead of you, cut them back to the bottom two leaves, and use your harvest to make pesto. Or use the flowering stems in bouquets; Thai basil is especially attractive.