Does it need full sun?

Yes, it thrives with at least six hours of direct sunlight daily.

Can I grow it indoors?

It grows well indoors if placed in a very sunny window or under grow lights.

Plant guide

Holy Basil.

Ocimum tenuiflorum

Pronounced OSS-ih-mum ten-yoo-ih-FLOR-um

Also known as Holy Basil, Krishna Tulsi, brush-leaf-tea, sacred basil

Holy Basil is a sacred and aromatic herb often grown for its medicinal properties and spiritual significance. It thrives in warm, sunny spots and brings a lovely fragrance to any garden. You will love how easy it is to keep this plant happy with just a little attention.

Another photo of Holy Basil — Photo by Navaneeth Sini George (CC BY) via gbif

At a glance

Care level: Easy
Plant type: Herbaceous perennial
Light: Full sun
Indoor light: Direct sun
Water: Every 2 to 4 days
Mature size: 2 to 3 feet
Growth rate: Fast
Hardiness: USDA 10 to 12
Bloom time: Mid to late summer

Care

Keep your plant in a warm area with plenty of sunlight to encourage bushy growth. Watch for wilting leaves, which usually signal that your plant needs a drink. Pinch back the tips regularly to help the plant stay full and prevent it from getting too leggy.

Watering: Keep the soil consistently moist but never soggy.
Feeding: Use a balanced liquid fertilizer once a month during the growing season.
Pruning: Regularly pinch off the top sets of leaves to encourage branching.
Repotting: Repot when the roots begin to crowd the container.
Soil: Well draining, fertile soil
Soil pH: 6.0 to 7.5
Temperature: 10 to 35°C
Humidity: 40 to 70%
Drought tolerance: Moderate
Lifespan: Short lived perennial, typically 1 to 3 years.
Fragrance: Strong
Deer and rabbits: Moderate

Signs it needs repotting

Roots growing out of the drainage holes.
Water running straight through the pot without soaking in.
Stunted growth during the active season.

Safety

People: This plant is generally safe for human consumption in culinary amounts.
Children: The plant is non toxic, but the small seeds and stems could pose a minor choking hazard if ingested by very young children.
Contact allergens: Some individuals may experience mild skin irritation from the essential oils in the leaves.
Airborne allergens: The pollen can trigger mild reactions in highly sensitive individuals during the peak flowering season.
Edibility: While commonly used in teas and traditional medicine, consult a healthcare professional before regular consumption if you are pregnant or taking blood thinners.

How to identify it

Opposite, oval shaped green leaves
Slightly serrated leaf edges
Small purple or white flowers
Strong, spicy, clove like scent
Hairy stems and foliage

Height: 0.3 to 0.6m
Spread: 0.3 to 0.45m
Leaves: green, purple, evergreen
Flowers: pink, purple, white, 0.5 to 1cm
Fruit: brown, Late summer to autumn

Problems to watch for

AphidsCommon
BoltingCommon
Root RotCommon
Downy MildewUncommon
Powdery MildewUncommon
Spider MitesUncommon
WhiteflyUncommon

By symptom

Plant problems by symptom

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Growing it

Propagation: seed, cuttings
When to plant: spring, early summer
Overwintering: Bring containers indoors before the first frost. Keep in a bright, warm spot and reduce watering during the winter months.
In containers: It is an excellent container plant, thriving in pots with good drainage and a minimum size of 20 centimeters.

Seed Sowing

1. Fill a tray with moist seed starting mix.
2. Sprinkle seeds on the surface and lightly cover with soil.
3. Keep warm and moist until germination occurs in 1 to 2 weeks.

Stem Cuttings

1. Take a 10 centimeter cutting from a healthy stem.
2. Remove lower leaves.
3. Place in a glass of water until roots appear.
4. Pot into soil.

Planting near tomatoes may improve their overall vigor and flavor.

Grows well with

Tomato · They are classic companions that grow well together in the garden.
Pepper · Both plants enjoy similar soil and light conditions.

Similar species

Sweet Basil · A close relative commonly used for pesto and culinary dishes.

Science

Family: Lamiaceae
Genus: Ocimum
Order: Lamiales
Class: Magnoliopsida
Native range: Indian subcontinent and tropical regions of Southeast Asia.
Conservation: Not of conservation concern, though wild populations are sometimes overharvested for medicinal trade.

It grows as an annual or short lived perennial in tropical climates, often colonizing disturbed soils.

Value to wildlife: nectar source
Pollinators: bees, butterflies
Uses: culinary herb, medicinal tea, ornamental container plant, spiritual offering

Through the year

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Flowering

Fruiting

Foliage

Ecological indicators

Salinity: 2/9
Soil reaction: 6/9
Light: 8/9
Temperature: 8/9
Moisture: 5/9
Nutrients: 6/9

Taxonomy resolved against GBIF.

Questions people ask

Does it need full sun?: Yes, it thrives with at least six hours of direct sunlight daily.
Can I grow it indoors?: It grows well indoors if placed in a very sunny window or under grow lights.

Where the name comes from

The name Ocimum comes from the Greek word for fragrant, while tenuiflorum refers to its slender flowers.

Good to know

It is a staple in Ayurvedic medicine.
The leaves have a distinct clove like scent.
It is often referred to as Tulsi.
It grows best in full sun.

Keep your holy basil growing

This page is a general guide. Save your plant in Pocket Botanist and you get care reminders timed for this plant, plus a care history that shows what worked.

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This guide was generated with AI on September 26, 2026 and checked against GBIF taxonomy. It is general information, not horticultural or veterinary advice. Read about how we build these guides.