Productivity in crop cultivation in developing countries is claimed to be critically dependent on fertilizer inputs. However, chemical fertilizers are for a variety of reasons not available or not affordable to sub-Saharan small holder farmers. This has shifted the attention to local alternatives, like organic fertilizer. In this paper we investigate empirically the relationship between crop production and organic fertilizer use and combinations of different types of
fertilizer use. For this purpose we estimate crop production equations on the basis of an annual district panel data-set for Malawi (26 districts, 1999/2000-2009/2010), using a methodology for estimating agricultural production with endogenous heterogeneous technology. The empirical evidence supports a significant, positive relationship of substantial size between organic fertilizer use and crop production, for nearly all crops in varying combinations. Chemical fertilizer is only significant for maize and tobacco, and hence only for these two crops a joint positive relationship between crop production and organic and chemical fertilizer use exists. Organic fertilizers elasticity and chemical fertilizer elasticity have a similar size. A combination of high levels of organic and chemical fertilizer in maize and tobacco corresponds with an increase of production per hectare of close to 80%. Organic and chemical fertilizer are
complements in maize cultivation and substitutes in tobacco cultivation.