The soil in which coffee is grown must be rich, moist, and absorbent enough to accept water
readily, but sufficiently loose to allow rapid drainage of excess water.
The best soil is composed of leaf mold, other organic matter, and disintegrated volcanic rock.
Although coffee trees are damaged easily by frost, they are cultivated in cooler regions.
The growing temperatures range from 13° to 26° C (55° to 80° F).
Altitudes of coffee plantations range from sea level to the tropical frost level,
about 1800 m (about 6000 ft). Robusta coffee and Liberian coffee grow best at altitudes below
900 m (3000 ft); Arabian coffee flourishes at the higher altitudes.
The seeds are planted directly in the field or in specially prepared nurseries.
In the latter case, young selected plants are transplanted later to the fields, this
promotes the growth of stronger, healthier trees with heavier yields.
The coffee tree produces its first full crop when it is about five years old.
Thereafter it produces consistently for 15 or 20 years. Some trees yield 0.9 to 1.3 kg (2 to 3 lb)
of marketable beans annually, but 0.45 kg (1 lb) is considered an average annual yield.
Our method of harvesting is based on selective picking the fruit. Beans picked by this process
ensures that only the best and, the ripest beans are picked. Washing and drying the beans, then
removing the outer coverings is next. The final product, called green coffee, is sorted by hand
to remove defective beans and extraneous material and is then graded according to size.
The beans are heated in
rotating, horizontal drums that provide a tumbling
action to prevent uneven heating or scorching.
Temperatures for roasting range from about 193° C (about
380° F) for a light roast, through about 205° C (about
400° F) for a medium roast, to about 218° C (about 425°
F) for a dark roast. The roasted beans are cooled
rapidly to preserve quality and flavor.