How to Grow Basil Plants

Sweet Basil in pot against white wall background
Liz Whitaker/The Image Bank/Getty Images

Basil plants are one of the most popular herbs to grow and also one of the easiest. Basil is a member of the mint family. It is closely identified with Italian cooking, although it is originally from India. The extremely aromatic leaves also have a delightful variety of flavors, from the slightly lemony-mint of sweet basil to cinnamon, and licorice. Leaf colors span from rich green to deep purple, with smooth or crinkled leaves.

The flowers are insignificant but very popular with bees.

All types of basil grow easily in warm, sunny weather. The leaves are commonly used in cooking, but the flower buds are also edible.

Botanical Name

Ocimum basilicum

Common Name

Basil

Hardiness Zones

Basil plants can be grown as perennials in USDA hardiness zones 10 and above, but for most of us, it is a tender annual that only lasts until the first frost and must be replanted every season.

Mature Plant Size

The size of your plant will depend on the variety, the growing conditions, and how much you harvest. "Sweet Basil" can reach 6 ft. tall, but grows to about 2 - 3 ft. for most gardeners. Continually pinching and using your basil will coax it into becoming bushy, with more leaves. There are also short 6-inch dwarf varieties, which work especially well in pots.

Sun Exposure

Basil grows best in full sun. You will have fewer disease problems and sturdier plants.

Days to Harvest

Basil is ready to start harvesting in about 60 - 90 days, from seed. Frequent harvesting or pinching of the leaves will keep your basil plants producing fresh leaves longer. You can pinch off individual leaves or take the tops off of a large plant if you need a large amount.

You'll want to prevent your basil from blooming for as long as possible, by harvesting or pinching off the top sets of leaves as soon as the plant reaches about 6 inches in height.

If the plant sets flowers, it is on its way to going to seed and will not grow bushy and fill out with a lot of tasty leaves. Once a basil plant goes to seed, the existing leaves begin to lessen in flavor, so don't be afraid to cut and use it, as soon as possible . The flowers are edible, too, so don't despair if a few plants get ahead of you.

Cooking with Basil

Basil can be used in cooking, generally added at the end to keep its fresh taste and color. Basil can also be used fresh in salads, on sandwiches or even as a wrap, for instance around cheese cubes.

The Best Ways to Preserve Basil

Basil can be dried or frozen, for use after harvest. Dried basil is convenient, but loses some of its flavor. Frozen basil has a stronger basil flavor than dried, but you've lost the texture. Use it in cooked dishes.

Using Basil in Your Garden Design

Basil is traditionally planted alongside tomato plants. It's said they help each other grow, but it may just be for convenience in harvesting. However, basil does not need to remain in the vegetable or herb garden. Some of the shorter, purple varieties, like "Spicy Globe," actually make nice edging plants in the ornamental garden, if you don't have problems with animals eating them.

And any type of basil can easily be grown in containers. Give each plant at least a 12-inch pot in a sunny site and it should do very well.

Basil Growing Tips

Basil is a heat lover. Don't bother planting it until the daytime temperatures remain in the 70s F. and night temperatures are above 50 degrees F. Seeds can be started indoors 3 - 4 weeks before your last spring frost date. Unlike many Mediterranean herbs, basil likes a somewhat rich soil and doesn't like to be kept dry.

Space plants about 10 inches apart. They will bush out. Begin pinching the tops off once the plants reach about 6 inches in height. If you don't pinch or harvest, the plants will grow tall and gangly, with few leaves, and will bolt to seed.

Basil is very sensitive to frost and will be one of the first plants to go in the fall.

You can extend the season slightly by covering your plants with row covers when frost is threatened. Don't let the row cover touch the leaves. Frost on the outside of the row cover is enough to damage the tender leaves and will likely turn them black.

If you live in a frost-free area, you might want to allow some basil plants to set flowers and self-seed in your garden. Not all varieties will do this successfully.

Growing Basil Indoors

You can grow basil indoors, from seed, seedling or cuttings from your vegetable garden plants. Provide direct sunlight and warmth and feed monthly. An underfed basil plant, indoors or out, will have pale green leaves.

Suggested Basil Varieties to Grow

  • "Genovese": Larger leaves than 'Sweet Basil', with all the flavor.
  • "Cinnamon" or "Mexican Spice": Green foliage, purple flowers, with a spicy, cinnamon scent.
  • "Finissimo Verde a Palla" & "Spicy Clove": Quick growing compact plants that are great for containers and edges.
  • "Lemon": Gives a fresh lemony tang to pesto. Small leaves can be harder to harvest. The cultivar "Sweet Lemon Dani" or "Sweet Dani" has a lemon flavor and larger leaves.
  • "Red Rubin": Keeps purple color throughout the season with great flavor. Wonderful for flavoring vinegar.

Pest and Problems of Basil

Aphids are the biggest basil pest, especially if grown indoors. Beetles and slugs can be a nuisance outdoors, creating holes in the leaves.