Cocoa, Theobroma cacao, is an evergreen tree in the family Malvaceae, grown for its seeds (beans) which are used primarily in the manufacture of chocolate. The cocoa plant is a branching tree with simple, pointed (lanceolate) leaves which can measure up to 61 cm (24 in) long and 10 cm (4 in) wide. The tree produces clusters of pale yellow flowers each with five petals and sepals. The cocoa pods (drupes) can be green-white, yellow, purplish or red in colour each of which contains 20–50 seeds, usually arranged in five distinct rows. The cocoa tree can reach 4–20 m (13-66 ft) in height and can live for up to 40 years although the commercial life of a cocoa tree is usually about 25 years. Cocoa may also be referred to as cacao, koko or Kacao and originates from upper Amazon region of South America.

Uses

Cocoa beans are primarily used in the production of chocolate, cocoa powder and cocoa butter for consumption. Cocoa butter is also used in the cosmetic industry.

Propagation

Basic requirements
Cocoa trees are tropical plants and grow best in humid conditions at temperatures between 18 and 32°C (65–90°F). It is typically grown in regions where daytime humidity reaches up to 100% and night time humidity is between 70 and 80%. The plants require a deep, fertile and well-draining soil with a pH of 5.0–7.5 for optimum development. Cocoa is usually grown in tropical lowland areas is sensitive to drought. It should typically not be grown in regions which experience less than 1 cm of rainfall for periods in excess of 3 months.

Seeds
Cocoa seeds from healthy, ripe pods remain viable for 3 weeks and are usually planted straight after harvest to produce new seedlings. Seeds should be planted in a fiber basket or plastic nursery bag filled with clean soil and placed in a shaded place protected from the sun to prevent scorching. Seedlings grow quickly and are ready to be transplanted after 4–6 months.

Vegetative propagation
Cocoa can also be vegetatively propagated via cuttings, marcotting and budding. Cuttings should have 2–5 leaves and 1 or 2 buds. Leaves should be cut in half before placing the cutting in a pot and covering with polyethylene to allow roots to develop. Marcotting is achieved by removing a strip of bark from a tree branch and covering the area with a layer of sawdust before covering it with polyethylene. The covered area will develop roots and can then be removed and planted. The final method, called budding, can be used to rejuvenate older plantings and involves excising a bud and positioning it under a flap of bark on another tree. The join is then sealed with raffia and waxed tape. Once the bud begins to grow the tree above the new growth should be removed.

Planting and shading
Seedlings are usually planted in the ground when they are 4–6 months old. The young trees are delicate and require some protection from strong sunlight and wind damage. Protection is usually provided by planting seedlings next to mother trees. This shading also helps to prevent the trees from growing too tall, keeping them at a manageable size for maintenance and harvest. Shade trees are usually other crops such as banana, plantain coconut or rubber. Cocoa seedlings should be planted 3–4 m (10–13 ft) apart and 3–6 m (10–20 ft) from the shade trees. The shading can be reduced once the cocoa trees have formed a closed canopy but some should be retained to reduce water stress and insect damage.

General care and maintenance
The cocoa nursery should be kept weed free while the seedlings established but generally do not require weeding after the trees have formed a closed canopy as the lack of light under the trees prevent any further growth. Cocoa should be supplied with additional nutrients by fertilizing, particularly when trees are grown on poor soils or without shade. Organic fertilizers are generally preferable to inorganic ones as they do not deplete the soil organic content and conserve soil structure. The amount of fertilizer required is dependent on many factors, such as the age of the tree and the amount of shading but mature cocoa generally requires at least 50–100 kg/ha of nitrogen, 25 kg/ha of phosphorus, 75 kg/ha of potassium and 15 kg/ha of magnesium each year.

Source: Plant Village.