Declining soil fertility is a major challenge to crop production in Sub-Saharan Africa (SSA) countries though the degree of depletion varies from country to country and within localities. The causes are diverse and complex and vary from country to country. In general, continuous cropping, abandoning of traditional soil fertility restoration practices, crop nutrient removal, depletion of organic matter and soil erosion are universal causes of soil fertility decline in Africa. The problem can be addressed to an appreciable extent through the applications of inorganic fertilisers. Indeed, dramatic increases in the yields of several crops have been reported in Africa due to the use of this input. However, the use of this important input is increasingly being limited by skyrocketing costs. Though the use of farm yard manure (FYM) and compost could be alternatives to fertiliser use, there are a number of factors that limit their use as organic fertilisers. Thus, there is a need to develop easy to use, relatively affordable, locally available and sustainable methods of soil fertility improvement technology for increased crop production in smallholder farming systems in Africa.

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