Thai Sweet

Family: Lamiaceae Herb

Fragrant as a warm evening garden—Thai Sweet basil releases a bright, sweet-anise perfume with a gentle clove lift as soon as you brush its leaves.

The foliage is tender and lush, with a smooth, medium-fine texture and an aromatic sweetness that makes it a standout for fresh garnishing, fragrant sauces, and quick pickling-style preserves. Grow Thai Sweet for a steady harvest at about 50 days, when plants are vigorous and richly leafed for repeated picking.

Light: Full SunMaturity: 50 DaysHabit: Upright

Planting schedules and alerts are optimized for Columbus (Zone 6b).

Crop Dates

Milestone	Date
Start Indoors	Mar 21st
Last Frost	Apr 25th
Transplant / Sow Outdoors	Jun 6th
Harvest Begins	Jul 26th
Harvest Ends	Oct 16th

Crop Details

Trait	Value
Days to Maturity	50
Sun Requirements	Full Sun
Growth Habit	Upright
Support Needed	None
Planting Depth	Normal
Germination Temp (°F)	75
Min Soil Temp (°F)	60
Min Night Temp (°F)	50
Harden Off (days)	10

Culinary Notes

Chef's Note

Thai Sweet basil is all about timing: add it late so the leaf stays tender and the sweet-anise aroma doesn’t turn dull. Its clove lift plays especially well with salty fish sauce and bright lime—like a fragrant top note over heat and fat.

Best Uses

torn-leaf garnish for hot bowls (pho, curry, brothy noodles) so the aroma hits before it cools
quick wok or pan-stir sauces—basil goes in late to keep that anise-sweet edge
Thai-style basil stir-fry with salty fat (use sparingly at the end for maximum fragrance)
sweet vinegar quick pickling of basil stems/leaves for punchy, aromatic snacking

Flavor Profile

sweet-anise perfume gentle clove-like lift tender, lush leaf texture aromatic sweetness that stays bright in warm cooking

Kitchen Pairings

fish sauce lime juice garlic chili coconut milk brown sugar

Frequently Asked Questions

What pest or disease commonly affects Ocimum basilicum (Thai sweet basil), and how can I fix it?

Thai sweet basil (Ocimum basilicum var. thyrsiflora) is especially prone to downy mildew and leaf spot in humid weather. Improve airflow by spacing plants well and watering at the soil line (not the leaves), then remove badly infected leaves promptly to slow spread. If conditions stay humid, use an approved downy mildew treatment labeled for basil and follow the label timing before symptoms worsen.

How often should I water Thai sweet basil during peak growth?

During active growth (roughly weeks 2–8), keep the root zone consistently evenly moist, not soggy. Water when the top 1 inch of soil feels dry; in warm Full Sun, this is often about 1–2 times per week depending on your soil and container size. Aim for thorough soaking each time so moisture reaches the basil’s shallow roots, and avoid frequent light sprinkles that leave the soil surface wet but the roots dry.

How do I know when Thai sweet basil is ready to harvest?

Harvest when plants are about 8–12 inches tall and before flowering starts—around 45–50 days from sowing for best flavor and tenderness. Pinch or cut above a leaf pair to encourage branching, and take small harvests early in the morning for the most aromatic leaves. Once flower buds form, leaf quality drops, so harvest regularly until you see flowering clearly.