In Ethiopia, coffee grows at various altitudes, ranging from 550-2,750m above sea level. However, the bulk of coffee arabica is produced in the eastern, southern and western parts of the country, which have altitudes ranging from 1,300 – 1,800 masl.
Annual rainfall in the coffee-growing regions of the country varies from 1,500-2,500mm. Where precipitation is less, as in the eastern part of the country, which has only 1,000 mm per annum, it is supplemented with irrigation. It is not only the total rainfall which is important for good production but also its eight-month distribution. Rainfall distribution in the southern and eastern parts of the country is bi-modal, and in the western part is mono modal. These distribution patterns enable the country to harvest coffee at different times of the year, ensuring a supply of fresh beans all year round.
Coffee arabica grows best in the cool, shady environment of the forests of the Ethiopian highlands. The ideal temperature for coffee arabica is considered 15-25ºc. This temperature prevails in most of the country’s coffee-growing areas.
- Planting Material
Because the country is the center of origin of coffee arabica, the variability of the plant character is very wide, making possible planting materials which are disease-resistant, high-yielding and of top quality. This is nature’s gift to Ethiopia in particular and to the world in general, and it requires special care and proper utilization.
The soils in the southern and western parts of the coffee-growing regions of Ethiopia are of volcanic origin, with a high nutrient-holding capacity for clay minerals. The Mesozoic layer, made up of sandstone and calcium carbonate, is found in the eastern part of the coffee-growing region. All the coffee-growing regions have fertile, friable, loamy soils, with a depth of at least 1.5m. The topsoil is dominantly dark-brown or brownish in color, with a PH ranging mostly from 5-6.8 (water extract). One outstanding characteristic of the soil is that its fertility is maintained by organic recycling, i.e., through litter fall, pruning and root residue from the perennial, coffee and shade trees.
In addition, the small coffee farmers, who are the major producers, use organic fertilizers to supplement the natural fertility of the soil. Most buyers know that the bulk of coffee produced in Ethiopia qualifies as organically-grown.