Holy basil (Tulsi)

Ocimum tenuiflorum

Sacred plant in Hindu tradition and a major Ayurvedic adaptogen. Distinct from culinary basil — clove-scented foliage, small purple flower spikes.

Hardiness ratings

Holy basil (Tulsi) hardiness across the four zone systems
SystemRatingTemperature rangeHow to read it
USDA hardiness zone Zone 9–12 −6.7 °C to 15.6 °C Zones where it can be grown as an annual — not a frost-tolerance rating
RHS hardiness rating H3 −5 °C to 1 °C Plant needs at least this level of cold tolerance
Canadian plant hardiness zone Zone 9 −1 °C and warmer Zones where it can be grown as an annual — not a frost-tolerance rating
Australian (ANBG) zone Zone 5–7 5 °C and warmer Zones where it can be grown as an annual — not a frost-tolerance rating

As a tender annual, Holy basil (Tulsi) doesn't overwinter — the zone range shows where the growing season supports it. See the RHS rating for its actual cold tolerance.

About Holy basil (Tulsi)

Holy basil, or tulsi, is distinct from the sweet basil used in Italian cooking, both botanically and culturally. It holds a sacred place in Hinduism, where it is grown in courtyards and temple grounds and treated with religious respect rather than as a culinary herb. Its flavour is markedly different from sweet basil — clove-like and peppery, from a higher concentration of eugenol, the compound that dominates cloves. It is a short-lived perennial in warm climates but is usually grown as an annual elsewhere, and like other basils it is decisively stopped by frost rather than merely checked.

Growing notes

  • Three principal varieties — Rama (green), Krishna (purple), Vana (wild) — with subtly different aromatic profiles
  • Perennial in zone 9+, grown as a tender annual elsewhere
  • Always consult a qualified medical or herbal practitioner before using any plant medicinally

Categories

Related plants

Cross-check Holy basil (Tulsi) against your zones

Reference

Holy basil (Tulsi) on Wikipedia