Does it need a lot of light?

Yes, it thrives in full sun and requires high light intensity for optimal growth.

Is it easy to grow in pots?

It grows well in containers if they are large enough to accommodate the root system.

Plant guide

Cannabis.

Cannabis sativa

Pronounced kan-uh-bis suh-TEE-vuh

Also known as Grass, Hashish, Hemp, Hemp, Marijuana, Hashish, Hash, Marijuana, Mary Jane

Cannabis is a fast growing annual herb known for its distinct palmate leaves and aromatic resin. It thrives in sunny spots with rich, well draining soil. You will find it grows quite quickly during the warm summer months.

At a glance

Care level: Moderate
Plant type: Annual herb
Light: Full sun
Indoor light: Direct sun
Water: Every 2 to 4 days
Mature size: 150 to 300 cm
Growth rate: Fast
Hardiness: USDA 2 to 11
Bloom time: Late summer to early autumn

Care

Keep the soil consistently moist but never soggy to prevent root issues. Watch for yellowing leaves as a sign of nutrient deficiency or overwatering. Ensure good airflow to avoid mold on the dense flower clusters.

Watering: Water whenever the top few centimeters of soil feel dry to the touch.
Feeding: Apply a balanced fertilizer during the active growing season.
Pruning: Trim lower fan leaves to improve light penetration and airflow.
Repotting: As an annual, this plant completes its life cycle in one season and does not require repotting.
Soil: Loamy, nutrient rich, well draining
Soil pH: 6.0 to 7.0
Temperature: 15 to 30°C
Humidity: 40 to 60%
Drought tolerance: Moderate
Lifespan: Annual, typically 4 to 8 months
Fragrance: Strong
Deer and rabbits: Moderate

Signs it needs repotting

Roots growing out of the drainage holes.
Stunted growth despite adequate light and nutrients.
Water running straight through the pot without soaking in.

Safety

People: The plant contains psychoactive cannabinoids that can cause significant physiological and psychological effects.
Pets: Cannabis is toxic to cats and dogs if ingested.
Children: Keep this plant away from children due to the potential for accidental ingestion of psychoactive compounds.
Contact allergens: Handling the foliage can cause contact dermatitis in sensitive individuals due to glandular trichomes.
Airborne allergens: The pollen is highly allergenic and can trigger severe hay fever symptoms during the flowering season.
Edibility: Consumption of raw or processed plant material is subject to strict legal regulations and health risks in many jurisdictions.

How to identify it

Distinctive palmately compound leaves
Serrated leaf margins
Strongly aromatic resinous glands
Tall upright central stem
Small inconspicuous flowers

Height: 1 to 3m
Spread: 0.6 to 1.5m
Leaves: green, dark green, deciduous
Flowers: white, green, yellow, 1 to 5cm
Fruit: brown, tan, Autumn

Problems to watch for

AphidsCommon
Fungus GnatsCommon
Powdery MildewCommon
Spider MitesCommon
Bud RotUncommon
ChlorosisUncommon
Root RotUncommon
ThripsUncommon
WhiteflyUncommon

By symptom

Plant problems by symptom

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Growing it

Propagation: seed, cuttings
When to plant: spring
Overwintering: This plant is an annual and will die back naturally as temperatures drop in autumn.
In containers: It grows well in large containers, ideally 20 liters or more, to support its vigorous growth.

Seed germination

1. Soak seeds in water for 12 hours.
2. Place seeds in moist paper towels until they sprout.
3. Plant sprouted seeds in soil at 1cm depth.

Cuttings

1. Take a 10cm cutting from a healthy vegetative branch.
2. Dip the cut end in rooting hormone.
3. Place in a moist growing medium under high humidity.

Plant aromatic herbs nearby to help deter common insect pests through natural scent masking.

Grows well with

Basil · Its strong scent can help mask the plant's odor from pests.
Dill · It attracts beneficial predatory insects that help control pest populations.

Similar species

Japanese Maple · The leaf shape is often compared to this plant, though they are unrelated.

Science

Family: Cannabaceae
Genus: Cannabis
Order: Rosales
Class: Magnoliopsida
Native range: Central and South Asia
Conservation: It is widely cultivated and not considered endangered, though wild populations are often protected or managed.

It is a ruderal species that quickly colonizes disturbed soil and open areas.

Value to wildlife: pollen source
Pollinators: bees, butterflies
Uses: fiber production, seed oil, ornamental, medicinal research

Through the year

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Flowering

Fruiting

Foliage

Ecological indicators

Salinity: 2/9
Soil reaction: 6/9
Light: 8/9
Temperature: 7/9
Moisture: 5/9
Nutrients: 7/9

Taxonomy resolved against GBIF.

Questions people ask

Does it need a lot of light?: Yes, it thrives in full sun and requires high light intensity for optimal growth.
Is it easy to grow in pots?: It grows well in containers if they are large enough to accommodate the root system.

Where the name comes from

The name Cannabis is derived from the Greek word kannabis, while sativa means cultivated or sown.

Good to know

The plant is dioecious, meaning it has separate male and female individuals.
Hemp fibers are incredibly strong and have been used for rope and textiles for centuries.
It grows very rapidly during the long days of summer.

Also in

Plants toxic to cats and dogs

Keep your cannabis growing

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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.