Impact of Alternative Soil Fertility Management Options on Maize Productivity in Malawi’s Smallholder Farming System

This paper focuses on smallholder maize production in Malawi by investigating the link between productivity and soil fertility management. Many studies conducted in Malawi indicate declining levels of maize productivity thereby posing food security concerns, since maize is the staple crop for most areas of the country. This analysis focuses on the factors influencing productivity of maize among smallholder farmers, especially given the fears that unfavorable output and input market conditions throughout the 1990s may have compelled smallholder farmers into unsustainable agricultural intensification. Farm-household survey data is thus used to compare the productivity of smallholder maize production under integrated soil fertility (ISFM) and chemical-based soil fertility management. A normalized translog yield response model is estimated by imposing monotonicity and curvature correctness at the sample mean. The results indicate higher maize yield responses for integrated soil fertility management options, after controlling for the intensity of fertilizer application, labour intensity, seed rate, land husbandry practices and policy factors such as market access, extension and credit access. The estimated model is highly consistent with theoretical regularity conditions. Thus, the findings indicate that the use of ISFM increases maize productivity in comparison to the use of inorganic fertilizers. Since most farmers in the maize-based farming systems are crowded out of the agricultural input market and can hardly afford optimal quantities of inorganic fertilizer, enhancement of ISFM provides scope for enhancing maize productivity and food security especially where inorganic fertilizer is highly unaffordable and risky to use. Thus there is need for policy interventions to promote smallholder uptake of ISFM options. Finally areas of policy support in crop output and input market development, credit access and extension service provision are identified to enhance ISFM uptake in smallholder maize-based farming systems.