Soil fertility replenishment takes off in east and southern Africa uri icon


  • Given the acute poverty and limited access to mineral fertilizers, an ecologically robust approach is discussed. It is a product of more than 10 years of agroforestry research and development efforts by the International Centre for Research in Agroforestry (ICRAF) and its many partners in East and southern Africa. Both research and development dimensions are discussed. Leguminous tree fallows accumulate 100-200 kg N/ha in their leaves and roots in 0.5-2 years. In addition to supplying N in a sensible way and drastically increasing maize yields, leguminous tree fallows provide multiple benefits such as fuelwood production in situ, recycling of other nutrients, deep nitrate capture, pest management, soil and water conservation and carbon sequestration. There are two options for mineral fertilizers: imported superphosphates and diammonium phosphates, or indigenous phosphate rock. The biomass transfers of tithonia from western Kenya are discussed. The impacts of leguminous fallows, tithonia and rock phosphates in crop production and soil fertility and productivity are also discussed

publication date

  • 2002