How to Grow Holy Basil (Tulsi)

Growing guide

Overview

Holy basil, also called tulsi, is a tender perennial herb grown as an annual in most of North America. Its leaves have a clove-and-pepper flavor used in Indian cooking, teas, and Ayurvedic medicine. It needs full sun, moderate water, and well-drained soil, and it grows well in a 3-gallon container on a sunny balcony or windowsill.

Soil & planting prep

Use loose, loamy or sandy soil that drains well. A slightly acidic to neutral pH between 6.0 and 7.0 is ideal. If planting in the ground, space plants 12 to 18 inches apart and sow seeds just 1/8 inch deep, barely covering them.

When to plant

Start seeds indoors 4 weeks before your last frost date. Transplant seedlings outdoors only after the last frost has passed and nighttime temperatures stay above 50°F. In zones 10a–11b, where holy basil is perennial, you can also plant directly outdoors in spring once the soil warms.

How to plant

1. Fill seed trays with moist seed-starting mix and press seeds 1/8 inch deep, then cover lightly.
2. Keep trays at 70–75°F in bright light; seeds germinate in 7–14 days.
3. Harden off seedlings over 7–10 days by gradually exposing them to outdoor sun and wind.
4. After last frost, plant in full sun, spacing 12–18 inches apart in the ground or one plant per 3-gallon pot.
5. Water gently after planting and keep soil evenly moist but never soggy.

5 common mistakes to avoid

• Planting outdoors before the last frost: holy basil is frost-tender and will blacken and die; wait until nights stay above 50°F.
• Letting plants flower: once flower buds form, leaf flavor turns bitter and production drops; pinch off buds as soon as you see them.
• Overwatering in heavy clay: tulsi roots rot in soggy soil; amend with compost or grow in raised beds or containers.
• Growing in too much shade: full sun is required for strong oils and bushy growth; fewer than 6 hours of direct sun gives spindly, bland plants.
• Harvesting only the large lower leaves: this slows regrowth; instead, snip stem tips just above a leaf node to encourage branching.

Harvesting & storage

Begin harvesting 45–60 days after planting, once plants are 8–12 inches tall. Snip stem tips just above a leaf pair, never taking more than one-third of the plant at once. Use leaves fresh, or dry them in a warm, dark place and store in an airtight jar for up to a year.

Companion planting

Holy basil grows well with tomatoes, peppers, and oregano. Avoid planting it near rue or fennel, which can inhibit its growth.

Growing in containers

Holy basil is container-friendly and thrives in a 3-gallon pot with drainage holes. Use a quality potting mix and place the pot in full sun; bring it indoors before the first frost in cold climates.

Pro tips

Start indoors 4-6 weeks before last frost. Grow in a sunny window year-round in cold climates. Harvest before flowering to maintain flavour. Pinch flower buds regularly. Three varieties worth growing: Rama (mild), Krishna (purple, spicier), Vana (wild-type, very aromatic).