Cannabis is a flowering plant in the hemp family (Cannabaceae) that people have grown for fibre, seed and its resin for thousands of years. It was first domesticated in East Asia in early Neolithic times. The plant contains more than 560 known compounds, including THC, which is intoxicating, and CBD, which is not. Low-THC varieties grown for fibre, seed and CBD are called hemp.
Key facts
- Botanical name
- Cannabis sativa L.; many botanists regard indica and ruderalis as subspecies or varieties of one species
- Origin
- First domesticated in East Asia in the early Neolithic (Ren et al., 2021)
- Compounds
- More than 560 identified, including over 100 cannabinoids, terpenes and flavonoids
- Plant type
- Annual herb, usually with male and female flowers on separate plants
- Hemp
- Low-THC cannabis; UK licences only cover approved seed types with no more than 0.2% THC (Home Office, as of October 2026)
- UK status
- Cannabis is a Class B drug; growing any cannabis plant needs a Home Office licence
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What is the cannabis plant?
Cannabis is an herbaceous annual. Most plants are either male or female, although some cultivars carry both kinds of flowers on one plant (Canadian Food Inspection Agency). The female flowers carry most of the resin, which is where the plant makes its cannabinoids and terpenes.
A genome study of 110 plants from around the world found that cannabis was first domesticated in East Asia in early Neolithic times, and that today's hemp and drug-type cultivars all descend from an ancestral gene pool now represented by wild plants and landraces in China (Ren et al., 2021).
What are the types of cannabis plant?
Three names come up most often. How to classify them is debated: many botanists recognise one variable species, Cannabis sativa, while others separate indica and ruderalis as species or subspecies (McPartland and Small, 2020).
| Sativa | Indica | Ruderalis | |
|---|---|---|---|
| Typical shape | Tall, narrow leaflets | Compact, broad leaflets | Small, few branches |
| Flowering | Triggered by shorter days | Triggered by shorter days | Often flowers with age (autoflowering) |
| Main uses | Hemp for fibre and seed; drug-type cultivars | Drug-type cultivars, breeding | Breeding of autoflowering cultivars |
| Our guide | Cannabis sativa | Cannabis indica | Cannabis ruderalis |
These labels describe how a plant looks, not reliably what it contains. A study of more than 100 samples found that "sativa" and "indica" labels did not match genome-wide differences (Watts et al., 2021). Most plants grown today are hybrids.
What does the cannabis plant contain?
More than 560 constituents have been identified in cannabis (ElSohly et al., 2017), of which about 125 are cannabinoids (Radwan et al., 2021). The main groups are:
- Cannabinoids, found almost only in cannabis. THC causes the high; CBD does not.
- Terpenes, the aromatic compounds behind the smell, such as myrcene, limonene and pinene.
- Flavonoids and other plant compounds.
Cannabinoids act on the body's endocannabinoid system, a signalling network with two main receptors, CB1 and CB2. THC binds strongly to CB1 receptors in the brain, which is why it intoxicates.
What is the difference between cannabis, hemp and marijuana?
They are the same plant. "Hemp" means cannabis varieties with very little THC, grown for fibre, seed and CBD. "Marijuana", "weed" and "ganja" are everyday names for cannabis grown for its THC-rich flowers. In the UK, the Home Office only licenses hemp cultivation from approved seed types with no more than 0.2% THC, and the leaves and flowers remain controlled. Our article on cannabis, marijuana and hemp explains the differences in detail, and What is hemp? covers the crop itself.
How are cannabis plants grown?
Cannabis grows from seed through a leafy vegetative stage to flowering. Most varieties start to flower when the days get shorter. Hemp for fibre and seed is usually a field crop. Flower crops are also grown in greenhouses or indoors, where light and climate can be controlled.
In the UK it is an offence to grow any plant of the genus Cannabis without a Home Office licence, and that includes hemp. Our guide How is hemp grown? describes how licensed hemp farming works.
Is cannabis legal in the UK?
No. Cannabis is a Class B drug under the Misuse of Drugs Act 1971. Only the mature stalk, the fibre from it and the seeds are excluded from the legal definition (Home Office, 2024). Pure CBD is not a controlled drug. Our page Is CBD oil legal in the UK? explains what that means for CBD products.
From our production
Our hemp is grown in Central Switzerland. Many customers still believe CBD and hemp products are illegal, and many journalists don't know the difference between cannabis and hemp. It misleads consumers.
— Robin Roy Krigslund-Hansen, co-founder and CEO
Frequently asked questions
What is cannabis?
Cannabis is a flowering plant in the hemp family. It contains more than 560 known compounds, including THC, which is intoxicating, and CBD, which is not. Low-THC varieties are called hemp.
Is cannabis the same as weed or marijuana?
Yes. "Weed", "marijuana" and "ganja" are everyday names for cannabis, usually meaning plants grown for their THC-rich flowers. Hemp is the same species bred to contain very little THC.
Are CBD and cannabis the same?
No. CBD (cannabidiol) is one compound found in the cannabis plant. It does not cause a high, and pure CBD is not a controlled drug in the UK, while cannabis itself is Class B.
What are the different types of cannabis plants?
The names used most are Cannabis sativa, Cannabis indica and Cannabis ruderalis. Botanists disagree on whether these are separate species, and the labels do not reliably predict what a plant contains.
Can you grow cannabis plants in the UK?
Not without a Home Office licence. Growing any cannabis plant, including low-THC hemp, without one is an offence. Hemp licences only cover approved seed types with no more than 0.2% THC.
What are the long-term effects of cannabis?
Research links frequent, heavy use of THC-rich cannabis with problems with memory and attention, dependence and a higher risk of psychosis in some people. Our guide to THC summarises the studies.
Related guides
This article is general information about the cannabis plant, not medical or legal advice. It makes no claims about Formula Swiss products, which are cosmetic products for use on the skin. See our full disclaimer.
Last reviewed:
Sources
- Ren G, Zhang X, Li Y, et al. Large-scale whole-genome resequencing unravels the domestication history of Cannabis sativa. Sci Adv 2021. doi:10.1126/sciadv.abg2286
- Canadian Food Inspection Agency. The biology of Cannabis sativa L. (cannabis, hemp, marijuana).
- McPartland JM, Small E. A classification of endangered high-THC cannabis (Cannabis sativa subsp. indica) domesticates and their wild relatives. PhytoKeys 2020. doi:10.3897/phytokeys.144.46700
- Watts S, McElroy M, Migicovsky Z, et al. Cannabis labelling is associated with genetic variation in terpene synthase genes. Nat Plants 2021. doi:10.1038/s41477-021-01003-y
- ElSohly MA, Radwan MM, Gul W, et al. Phytochemistry of Cannabis sativa L. Prog Chem Org Nat Prod 2017. doi:10.1007/978-3-319-45541-9_1
- Radwan MM, Chandra S, Gul S, ElSohly MA. Cannabinoids, phenolics, terpenes and alkaloids of cannabis. Molecules 2021. doi:10.3390/molecules26092774
- Home Office. Drug licensing factsheet: cannabis, CBD and other cannabinoids. Updated 3 October 2024.
- Home Office. Low THC cannabis (industrial hemp) licensing factsheet. Updated 18 December 2025.
