Cannabis is very adaptable to soil and climatic conditions. It prefers a rich loamy soil with plenty of humus but it succeeds in ordinary garden soil and also in calcareous soils. When grown for fibre, it requires a mild temperate climate with at least 67cm annual rainfall, with abundant rain whilst the seeds are germinating and until young plants become established. Cannabis thrives on rich, fertile, neutral to slightly alkaline, well-drained silt or clay loams with moisture retentive subsoils, it does not grow well on acid, sandy soils. Of the many types of hemp, some are adapted to most vegetated terrains and climates. Cannabis is reported to tolerate an annual precipitation range of 30 to 400cm, an average annual temperature range of 6 to 27°C and a pH in the range of 4.5 to 8.2. Plants require little cultivation, except for weeding during early stages of growth. Hemp grows rapidly and soon crowds out weeds. After the plants are 20 cm tall, weeding is abandoned. Hemp tends to exhaust the soil of nutrients, though some nutrients are returned to the soil after plants are harvested. Hemp is commonly cultivated for its fibre, edible seed and oil in many areas of the world, it is also a socially acceptable drug in areas of Asia and the Middle East. However, it is illegal to grow in Britain and many other western countries (plus Australia and New Zealand) because it contains certain narcotic principles and is a commonly used narcotic drug. As Cannabis sativa has been cultivated for over 4,500 years for different purposes, many varieties and cultivars have been selected for specific purposes, as fibre, oil or narcotics. Drug-producing selections grow better and produce more drug in the tropics; oil and fibre producing plants thrive better in the temperate and subtropical areas. Many of the cultivars and varieties have been named as to the locality where it is grown mainly. However, all so called varieties freely interbreed and produce various combinations of the characters. The form of the plant and the yield of fibre from it vary according to climate and particular variety. Varieties cultivated particularly for their fibres have long stalks, branch very little, and yield only small quantities of seed. Varieties which are grown for the oil from their seed are short in height, mature early and produce large quantities of seed. Varieties grown for the drugs are short, much-branched with smaller dark-green leaves. Between these three main types of plants are numerous varieties which differ from the main one in height, extent of branching and other characteristics. At least one variety has been selected for its virtually insignificant content of the narcotic principles. This form is monoecious whereas most other forms are dioecious. There is also said to be a tall Chinese form that has no narcotic effect. However in 1999 even these varieties are illegal to grow in Britain without a special licence. Certain varieties do not form many side-shoots and these are the forms most commonly grown for their fibre. Plants grown in warmer climates tend to be best for medicinal use, whilst those grown in more northerly latitudes produce the better fibre. The seed is very attractive to birds and is often included in bird seed mixtures.

Seed - raw or cooked. It can be parched and eaten as a condiment or made into cakes and fried. The seed is quite tasty, but it is very difficult to separate from the husk. We have tried grinding the seed, husk and all, and eating it this way, but it does then have a very gritty texture. The seed contains about 27.1% protein, 25.6% fat, 7.4% carbohydrate, 6.1% ash. A nutritional analysis is available calculated on a zero moisture basis. A highly nutritious edible oil, rich in essential fatty acids, is obtained from the seed. Leaves. Used in soups. The leaves contain 0.215% carotene.

Seed - sow in early spring in the greenhouse. When they are large enough to handle, prick the seedlings out into individual pots and plant them out into their permanent positions in early summer. Seeds germinate well at low temperatures, but not below 1°C. The seed can also be sown outdoors in situ in mid spring.

Fluvial deposits on crags and stony slopes. It is occasionally found as a casual on waste ground in Britain. It is especially found as a weed of nitrogen-rich soils near human habitations