Thai Basil Care Tips: How to Grow Thai Basil

Thai basil is a variety of a broader species known as sweet basil (Ocimum basilicum). Some gardeners and chefs refer to it by the common names chi neang vorng, licorice basil, and anise basil. A member of the mint family, Thai basil can be recognized by its distinctive purple stem, decussate green leaves, and pink and purple flowers that appear in the late summer.

Basil leaves are one of the most ubiquitous ingredients in Thai cooking and can be found in a wide array of Thai food. Thai basil can also be found in kitchens throughout Southeast Asia. Many regional dishes in Vietnam, Cambodia, and Laos all feature Thai basil.

Thai basil is one variety of sweet basil, a plant that’s more commonly used in Italian cooking. Beyond regional cuisine differences, there are a few ways to tell Thai basil and sweet basil apart.

• Color: Thai basil plants have purple stems and dark green leaves, while sweet basil plants have green stems and bright green leaves.
• Leaf shape: Thai basil leaves are thin and small, while sweet basil leaves are large and oval-shaped.
• Flavor: Thai basil leaves have a distinctive flavor with bold notes of licorice and spice. True to its common name, sweet basil has a sweeter flavor and more peppery notes.
• Varieties: Three types of basil appear in Thai cooking. Beyond standard Thai basil, chefs also use lemon basil (which, true to its name, offers hints of citrus) and Thai holy basil (which is spicier and almost recalls the taste of cloves). Notable cultivars of sweet basil include lettuce leaf basil (Ocimum basilicum 'Crispum'), cinnamon basil (Ocimum basilicum 'Cinnamon'), and dark opal basil (Ocimum basilicum 'Dark Opal').

You can grow Thai basil from seed, or you can start with a young seedling purchased from a nursery. In either case, consider these general guidelines for growing Thai basil.

• Outdoors: Thai basil grows natively in tropical regions of southeast Asia. In North America, it does best in USDA hardiness zone ten. Thai basil grows well alongside rosemary, which is a fellow member of the mint family. When growing Thai basil in your garden, keep the soil consistently moist but not wet. A garden bed with slightly acidic soil is ideal.
• Indoors: Thai basil can thrive as an indoor houseplant when placed in a warm, sunny window—ideally a south-facing window. Give your potted plants well-draining soil and ample sun exposure. Water them frequently in their first year to help them take root.

Once your Thai basil plant is established, practice the following care tips.

1. 1. Water your plant lightly and frequently. Thai basil needs consistent watering, but if you overdo it, the plant's leaves will turn yellow and fall to the ground. You can avoid overwatering your plant by giving it small amounts of water frequently.
2. 2. Fertilize Thai basil in the growing season. Use a seaweed-based or fish-based fertilizer two to three times during the plant's growing season of spring and summer.
3. 3. Trim the flowers before harvesting. The purple flowers of a Thai basil plant look charming, but they require energy and nutrients. Clip off these flowers several days before harvesting the leaves so that the plant can direct water and nutrients toward the leaves themselves.
4. 4. Harvest the leaves properly. To keep your plant consistently producing new leaves, avoid leaving too much stem exposed. Use clean, sharp shears to cut off a bunch of leaves directly above a growth point so new leaves are encouraged to grow.

Grow your own garden with Ron Finley, the self-described "Gangster Gardener." Get the MasterClass Annual Membership and learn how to cultivate fresh herbs and vegetables, keep your house plants alive, and use compost to make your community—and the world—a better place.

Thai basil is a variety of a broader species known as sweet basil (Ocimum basilicum). Some gardeners and chefs refer to it by the common names chi neang vorng, licorice basil, and anise basil. A member of the mint family, Thai basil can be recognized by its distinctive purple stem, decussate green leaves, and pink and purple flowers that appear in the late summer.

Basil leaves are one of the most ubiquitous ingredients in Thai cooking and can be found in a wide array of Thai food. Thai basil can also be found in kitchens throughout Southeast Asia. Many regional dishes in Vietnam, Cambodia, and Laos all feature Thai basil.

Thai basil is one variety of sweet basil, a plant that’s more commonly used in Italian cooking. Beyond regional cuisine differences, there are a few ways to tell Thai basil and sweet basil apart.

• Color: Thai basil plants have purple stems and dark green leaves, while sweet basil plants have green stems and bright green leaves.
• Leaf shape: Thai basil leaves are thin and small, while sweet basil leaves are large and oval-shaped.
• Flavor: Thai basil leaves have a distinctive flavor with bold notes of licorice and spice. True to its common name, sweet basil has a sweeter flavor and more peppery notes.
• Varieties: Three types of basil appear in Thai cooking. Beyond standard Thai basil, chefs also use lemon basil (which, true to its name, offers hints of citrus) and Thai holy basil (which is spicier and almost recalls the taste of cloves). Notable cultivars of sweet basil include lettuce leaf basil (Ocimum basilicum 'Crispum'), cinnamon basil (Ocimum basilicum 'Cinnamon'), and dark opal basil (Ocimum basilicum 'Dark Opal').

You can grow Thai basil from seed, or you can start with a young seedling purchased from a nursery. In either case, consider these general guidelines for growing Thai basil.

• Outdoors: Thai basil grows natively in tropical regions of southeast Asia. In North America, it does best in USDA hardiness zone ten. Thai basil grows well alongside rosemary, which is a fellow member of the mint family. When growing Thai basil in your garden, keep the soil consistently moist but not wet. A garden bed with slightly acidic soil is ideal.
• Indoors: Thai basil can thrive as an indoor houseplant when placed in a warm, sunny window—ideally a south-facing window. Give your potted plants well-draining soil and ample sun exposure. Water them frequently in their first year to help them take root.

Once your Thai basil plant is established, practice the following care tips.

1. 1. Water your plant lightly and frequently. Thai basil needs consistent watering, but if you overdo it, the plant's leaves will turn yellow and fall to the ground. You can avoid overwatering your plant by giving it small amounts of water frequently.
2. 2. Fertilize Thai basil in the growing season. Use a seaweed-based or fish-based fertilizer two to three times during the plant's growing season of spring and summer.
3. 3. Trim the flowers before harvesting. The purple flowers of a Thai basil plant look charming, but they require energy and nutrients. Clip off these flowers several days before harvesting the leaves so that the plant can direct water and nutrients toward the leaves themselves.
4. 4. Harvest the leaves properly. To keep your plant consistently producing new leaves, avoid leaving too much stem exposed. Use clean, sharp shears to cut off a bunch of leaves directly above a growth point so new leaves are encouraged to grow.

Grow your own garden with Ron Finley, the self-described "Gangster Gardener." Get the MasterClass Annual Membership and learn how to cultivate fresh herbs and vegetables, keep your house plants alive, and use compost to make your community—and the world—a better place.