Heterogeneous effects of sustainable agriculture practices: Micro-evidence from Malawi

Are the effects of sustainable agricultural practices heterogeneous across agroecology and wealth in Malawi?Would a wealth-enhancing policy be associated with increased effectiveness of these practices? Focusing on a nationally representative set of Malawian agricultural households, the article answers the above questions by employing plot-level panel data matched with a set of geo-referenced rainfall and temperature records. The findings suggest a positive correlation between aggregate yield and the adoption of organic fertilizer. A similar result holds for legume intercropping and for hybrid seeds, which are associated to reductions in yield volatility between the two waves. Nevertheless, these effects appear heterogeneous across the agro-ecological zone of adoption, since a reduced number of farmers in selected locations can improve yields through the adoption of these practices. Further exploration suggests that less wealthy households show higher returns when adopting hybrid seeds or legume intercropping. Wealthier households, in contrast, report high yield only when treated with technology-enhancing practices, such as organic fertilizers and soil erosion control measures.