Cannabis. View of a hemp or marijuana plant Cannabis sativa, which contains an intoxicating drug. The Cannabis plant, seen amongst household plants, is native to central Asia. It is grown for its fibrous stems, its seed oil and the drug it contains. This fast-growing annual plant is a common weed in northern India. In good conditions it can grow to over five metres tall with numerous side branches. Male and female flowers are borne on different plants, the females being most potent. The drug is produced in minute resin glands on the plant surface, including the leaves, but is most concentrated in female flowers. Cannabis is a banned plant in many countries.