Rwanda Crop Calendar

Volcanic region with altitudes between 1,600 and 2,500m. Regular distributed rainfall, varying between 1,300 and 1,800mm and fertile, volcanic soils. The mean temperature is 17 ̊C.

Practices: Rich volcanic soils make this region suitable for cultivation of many high altitude crops. Soil depth is deep to moderate, but can be limited by bombs or lava, restricting these parts to forest, pasture or recreation. Apart from altitude, the main limitation for crop cultivation is shallow soil depth, which has been remedied by cultivation on small ridges created by ploughing or harrowing the fields. Main cultivated crops of this zone: potato, maize,beans and peas.

The central Plateau is characterized by hills and valleys. The eastern part distinguishes itself by the granitic parent rock material (Granitic Ridge). The Central Plateau is suitable for a wide range of crops adapted to the relatively low temperatures, however, soil conservation of the humus-bearing horizon is essential. Annual rainfall is between 800 to 1,200mm, with generally more rainfall in the West. Mean annual temperature 19-21 ̊C. Dry season lasts for two months, apart from the Southeast, where a dry season of three months is more common.

Practices: Population increases have resulted in pressure on the land, resulting in cultivation of small plots for most farmers. The soils of the Central Plateau have a high potential for a wide range of crops. Crop cultivation on the Granitic Ridge is mainly concentrated on the concave hillslopes, while the convex ridges are used for pasture and forest. In the Southeast, the soils are strongly variable, with humus-rich, gravelly soils on the upper slopes and more fertile and younger soils on the foot of the hillslopes. Slope gradients increase significantly in the South, where forestry is the only advised land use. Moderately deep soils. Main limitations are erosion risks and low water availability. Management for erosion prevention is usually required. Most important crops: sorghum, sweet potato, cassava and beans.

This zone is characterized by highlands with altitudes varying between 1,900 and 2,300m. The Congo-Nile Watershed Divide is a mountainous ridge in the West of Rwanda that divides rivers on the West to drain into the Congo watershed and on the East side to drain into the Nile watershed. Annual rainfall in the North ranges from 1,700 to 2,000mm and in the East from 1,200 to 1,600mm. The exceptions are the tops of the Nyungwe forest mountains in the South, where annual rainfall exceeds 2,000mm. The Buberuka highlands in the North of Rwanda consist of high altitude plateaus that reach elevations of 2,300m. Annual rainfall is approximately 1,200mm and the dry season lasts for one to two months (June-July). Mean temperatures are between 15-18 ̊C. The soils of the Buberuka highlands are considerably more fertile than those of the Congo-Nile Watershed Divide.

Practices: Mostly rainfed crop production. High population density has caused a shifting in land use from forestry to agriculture in the Watershed Divide. Livestock is an important wealth indicator. The main limiting factors in this zone are high altitude (hence, lower temperatures) and slope steepness. Soil fertility is low and erosion risk high. Steep hillslopes are solely suitable for forestry. Management practices such as terracing and fertilisation can greatly improve the suitability for crops. Most important crops: potato, maize, beans, peas.

Altitude varies between 1,250 and 1,600m. Annual rainfall is higher in the Eastern Plateau and Bugesera, ranging between 900 and 1,000mm, while in the Eastern Savanna annual rainfall remains below 900mm and is more erratic of nature. The average temperature is 21 ̊C and the dry season lasts for three to four months. Soils in the Eastern Plateau are humus-rich on the hill tops, but heavily eroded on the steep slopes that characterize the Eastern Plateau. The most suitable soils for agriculture in the Eastern Savanna are found in the large valleys that intersect the sloping landscape of the East.

Practices: Driest region of Rwanda, especially Eastern Savanna and central Bugesera. Eastern Savanna is mostly used for pasture. Main limiting factors are lack of rainfall and long dry seasons. Varying land use potentials, where the most suitable cropland is found in the eastern valleys and around the Muhazi lake. Careful management to prevent erosion and restore soil nutrient balance is required to ensure sustainable crop production. Irrigation techniques due to long dry season are necessary and drainage systems are required in valleys with poor drainage. Intercropping is a common practice. Most important crops: banana, cassava, beans and maize.

The Imbo is the smallest Agro-ecological zone of Rwanda, situated in the Southwest. It is located in the drainage basin of the Rubyiro river and comprises the alluvial valleys of the Rusizi and Rubyiro. This zone extends further South into the bordering country Burundi. It is the lowest region of Rwanda, with altitudes of 970 to 1000m and much of the area is covered by marshes. The average temperature is 24 ̊C and the dry season generally lasts for three months (June-August). Annual rainfall varies from 1,050mm in the South to 1,600mm in the North.

Practices: Very suited for gravitational irrigation. Relatively reduced cropping cycle because temperature and humidity are favourable for crops. Extensive zone for bovine grazing because of availability of natural pastures. Zone for cultivation of upland rice and oil palm without irrigation. Most important crops: cassava, banana, rice and beans.

This region, together with the Imbo zone, comprises the area between lake Kivu on the West and the Mountainous Watershed Divide on the East. Altitudes vary from 1,300m to 1,900m and annual rainfall from 1,150 to 2,000mm, which generally increases with altitude. The region bordering lake Kivu experiences less rainfall (up to 1,300mm), where the centre is significantly drier compared to the North and South. Annual temperature varies between 18 and 21 ̊C. Lake Kivu has a smoothing effect on the soil temperature, which can exceed 22 ̊C. Overall, the clayey soils are moderately to highly fertile and suitable for cultivation of numerous traditional and industrial crops. Dry season varies between 1 to 3 months (June-August).

Practices: The mild climate in the South in addition to the fine clayey soils in this region, creates good conditions for cultivation of many crops. Extending further North, moderately fertile soils on the gently sloping hillsides are alternated with strongly eroded, steep slopes. Erosion and loss of nutrients can be reduced with land management techniques, such as small terraces and intensive fertilisation. The main climatic limitations in this zone are leaching caused by intensive rainfall and heavily eroded soils on steep hillslopes. High population densities causes constraints to land availability and agricultural production. Most important crops: sweet potato, maize, groundnut, banana.