Urban agriculture in West African cities is characterized by fast crop rotations and high inputs and outputs on relatively small land areas. Scientists Steiner et al. used a novel approach to evaluate the economic realities of farmers in a semi-participatory trial where farmers both produced and applied biochar in their soils. They showed that the use of biochar prompted farmers to improve their plot management. They assess that labor considerations and the availability of feedstock determine mainly farmers technology for biochar production.