HeirloomContainer OK

Thai Basil

Ocimum basilicum

Large 2-3" long, turned-down leaves. This stunning basil is nearly black in color. Purple flowers and red leaves make an attractive garnish. Ht. 16-20".Edible Flowers: Use the flowers in any recipe that calls for basil, or to garnish drinks, salads, soups, pasta, and desserts. Flavor is of intense basil.

Harvest

74d

Days to harvest

📅

Sun

Full sun

☀️

Zones

10–10

USDA hardiness

🗺️

Height

0-3 feet

📏

Planting Timeline

Zone:

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

Start Indoors

Transplant

Harvest

Start Indoors

Transplant

Harvest

Showing dates for Thai Basil in USDA Zone 10

All Zone 10 herb →

Zone Map

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Thai Basil · Zones 10–10

What grows well in Zone 10? →

Growing Details

Difficulty

Easy to moderate

Spacing8-12 inches

SoilRich, well-drained soil with organic matter

pH6.0-7.5

Water1 inch per week, consistent moisture but well-drained

SeasonWarm season annual

FlavorStrong anise-licorice flavor with spicy, clove-like undertones

ColorGreen leaves with purple stems and purple flower spikes

Size2-3"

Zone-by-Zone Planting Calendar

Zone	Indoor Start	Transplant	Direct Sow	Harvest
Zone 10	January – January	February – April	—	April – December

Complete Growing Guide

Drainage: Good Drainage, Moist. Height: 0 ft. 4 in. - 3 ft. 0 in.. Spread: 0 ft. 4 in. - 1 ft. 2 in.. Spacing: 12 inches-3 feet. Growth rate: Rapid. Maintenance: Low. Propagation: Seed, Stem Cutting. Regions: Coastal, Mountains, Piedmont.

Harvesting

Bloom time: Summer

Edibility: Leaves and flowers in tea, as flavoring

Storage & Preservation

Fresh Thai basil keeps best at room temperature in a glass of water like cut flowers, lasting 7-10 days with daily water changes. Avoid refrigeration, which blackens leaves and diminishes the essential anise oils that make this variety special.

For preservation, freezing works exceptionally well—wash and dry leaves completely, then freeze whole leaves in single layers on baking sheets before transferring to freezer bags. Frozen Thai basil retains more flavor than dried and works perfectly in cooked dishes.

Drying Thai basil requires gentle heat—use a dehydrator at 95°F or hang small bundles in a dark, well-ventilated area. Properly dried leaves retain their purple-green color and concentrated flavor for up to one year. The flower spikes dry beautifully and make excellent additions to herbal teas. Oil infusions capture the complex flavor profile—pack clean leaves in neutral oil and store refrigerated for up to one month.

History & Origin

Origin: Tropical Africa and Asia

Advantages

+Edible: Leaves and flowers in tea, as flavoring
+Fast-growing
+Low maintenance

Companion Plants

Plant Together

Tomatoes

Thai basil repels hornworms and aphids while improving tomato flavor and growth

Peppers

Mutual pest deterrent, basil repels aphids and spider mites that attack peppers

Eggplant

Basil deters flea beetles and aphids that commonly damage eggplants

Oregano

Similar growing requirements and both herbs repel many of the same garden pests

Marigolds

Both plants repel nematodes and various flying insects, creating stronger pest control

Cilantro

Attracts beneficial insects like parasitic wasps that protect basil from harmful pests

Lettuce

Basil provides partial shade for lettuce while repelling aphids that damage leafy greens

Garlic

Natural fungicide properties help prevent fungal diseases that can affect basil

Keep Apart

Rue

Allelopathic compounds inhibit basil germination and stunt growth

Common Sage

Competes aggressively for nutrients and may inhibit basil's aromatic oil production

Cucumber

Different watering needs and cucumber's sprawling growth can overshadow and stress basil plants

Nutrition Facts

Calories

23kcal(1%)

Protein

3.15g(6%)

Fiber

1.6g(6%)

Carbs

2.65g(1%)

Fat

0.64g(1%)

Vitamin C

18mg(20%)

Vitamin A

264mcg(29%)

Vitamin K

415mcg(346%)

Iron

3.17mg(18%)

Calcium

177mg(14%)

Potassium

295mg(6%)

Per 100g serving. % Daily Value based on 2,000 calorie diet. Source: USDA FoodData Central (FDC #172232)

Pests & Disease Resistance

Resistance

Good resistance to fusarium wilt, better heat tolerance than sweet basil

Common Pests

Aphids, Japanese beetles, slugs

Diseases

Bacterial leaf spot, downy mildew in humid conditions

Frequently Asked Questions

How long does Thai basil take to grow from seed?▼

Thai basil takes 60-75 days from seed to first harvest, with germination occurring in 7-14 days under warm conditions. Indoor-started plants transplanted outdoors will produce harvestable leaves about 45-50 days after transplanting, while direct-sown plants need the full 60-75 days in most climates.

Can you grow Thai basil in containers?▼

Thai basil grows excellently in containers and actually prefers the controlled drainage pots provide. Use containers at least 8 inches deep and 10 inches wide, with high-quality potting mix. Container growing allows you to move plants indoors during cold spells and provides better control over soil moisture—critical for preventing root rot.

What does Thai basil taste like compared to sweet basil?▼

Thai basil has a completely different flavor profile from sweet basil—intense anise and licorice notes with spicy, clove-like undertones. It's much stronger and more complex than sweet basil's mild, slightly peppery taste. The flavor holds up better to cooking and actually intensifies in hot dishes, making it essential for authentic Asian cuisine.

Should you let Thai basil flower?▼

Unlike other basil varieties, you should allow Thai basil to flower. The beautiful purple flower spikes are edible, flavorful, and don't make the leaves bitter. Harvest the flowers for cooking or let them bloom for ornamental value—just pinch spent flowers to prevent excessive self-seeding unless you want volunteer plants next season.

Is Thai basil good for beginners?▼

Thai basil is moderately beginner-friendly once you understand its heat requirements. It's actually more forgiving than sweet basil regarding watering and humidity, but absolutely requires warm conditions. New gardeners in zones 8-10 will find it easier than those in cooler climates who must start seeds indoors and manage transplanting timing carefully.

When should I plant Thai basil seeds?▼

Start Thai basil seeds indoors 6-8 weeks before your last frost date, or direct sow when soil consistently reaches 65°F. In most areas, this means indoor starting in March-April for May transplanting, or direct sowing in late May to early June. Southern gardeners can direct sow earlier, while northern gardeners should stick to indoor starting for reliable results.