Africa Soil Health Consortium: Handbook for Integrated Soil Fertility Management

The continent of Africa continues to grapple with many episodes of hunger and low crop productivity in multiple locations. With the ever-growing population in the continent, farmers continue to grow crops on the same land year after year. Under such continuous use, soil fertility declines if nutrients removed in crop products are not returned to the soil. To deal with this problem mineral fertilizers are essential. But as fertilizers are more expensive in Africa than anywhere else, most farmers use none at all. In response, many countries have subsidized fertilizers, yet often ignore supportive agricultural practices, institutions and policies. Increasing the productivity of smallholder farmers requires a good understanding of yield gaps (i.e. differences between actual, obtainable and potential yield under prevailing economic conditions) as well as biophysical and socio-economic factors constraints that hinder the closing of exploitable gaps.

Integrated soil fertility management, commonly referred to as ISFM, is presented in this handbook as a key contributor to Africa's low soil and crop productivity and especially for the main staples in the continent that include maize, beans, rice, cassava, bananas, sorghum, millet and other crops. In this context ISFM is defined as a set of soil fertility management practices that include the integrated use of mineral fertilizers, organic inputs and improved germplasms combined with the knowledge on how to adapt these practices to local conditions which are aimed at optimizing efficient agronomic use of the applied nutrients and thereby improving crop productivity. In this definition, all inputs need to be managed following sound agronomic and economic principles. ISFM cannot work if not supported by governments that are responsible for fertilizer imports, an enabled extension service that is critical to delivering the technology to the farmers, as well as a vibrant agro-dealer private sector that ensures efficient fertilizer and seed availability and distribution.