This herbaceous perennial is native to Southeast Asia.
Its edible leaves are traditionally used in Southeast Asian cuisines and offer a spicy, licorice-like flavor and aroma.
In the United States, Thai basil plants are hardy in zones 10-11 but are typically grown as annuals.
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How to Plant Thai Basil
Likesweet basil, Thai basil plants are easy to grow.
Start seeds indoors about six weeks before your last frost date in the spring.
Plant or thin Thai basil seedlings to put about 12 inches between plants.
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you’ve got the option to also plant Thai basil seeds or seedlings in containers.
Thai basil plants bloom in mid-to-late summer, depending on your region.
Pinch back the tiny purple flowers to keep the plant from setting seed and encourage leaf growth.
The Spruce / Jayme Burrows
Soil
Plant Thai basil in rich, well-drained soil that holds moisture well.
Water
Keep your Thai basil plant’s soil consistently moist with regular watering during periods without rain.
Temperature and Humidity
Thai basil prefers the warm, humid conditions of its native region.
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Temperatures below 50 degrees can stunt the plant’s growth.
Fertilizer
If you plant Thai basil in rich soil, it shouldn’t need any fertilizer.
This is especially beneficial when you’re pinching back plants to promote growth or harvesting frequently.
Harvesting lower on the plant can inhibit growth.
Frequent harvesting, as often as every other day, will encourage more vigorous regrowth.
Keep the glass at room temperature, as refrigeration damages basil leaves.
Change the water every few days and use as needed.
How to Grow Thai Basil Plants in Pots
Thai basil grows well in containers.
Put a single plant in a 12-inch deep pot with drainage holes and rich, loose potting mix.
Do this on subsequent branches and use the leaves in recipes.
You’ll need sharp scissors or pruners, a small glass or jar, and water.
Space rows about 18 inches apart.
Thin seedlings to eight to 12 inches apart to give mature plants adequate airflow and room to grow.
Pick off Japanese beetles and drop them in a bucket of soapy water.
Use insecticidal soap to treat aphids and diatomaceous earth or slug baits to kill slugs.
Plant diseases like fusarium wilt and bacterial leaf spot can affect Thai basil plants.
The best way to avoid these is by watering the soil directly to avoid getting the leaves wet.
Yes, Thai basil is easy to grow in the right conditions.
The main consideration after planting is keeping the soil moist in the heat of summer.
Thai basil plants are perennial in tropical climates and come back each year.
