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Urban farmers in Harare grow vegetables in soils fertilised with poultry manure (PM) and sewage sludge (SS). Feed and storage management influence nutrient supply of these organic amendments. Nitrogen mineralisation of PM and SS were determined in a non-leaching and aerobic incubation experiment. Effects of these amendments on yield, nitrogen (N) and heavy metal uptake by vegetables grown in soils treated with 150 kg N ha −1 from compound mineral fertiliser (7 N:14 P₂O₅:7 K₂O), PM (2.26% N) and SS (3.26% N) were studied. Phosphorus (P) and potassium (K) were added at rates of 50 kg P ha −1 and 60 kg K ha −1 , respectively. A second crop was grown without adding amendments. Poultry manure mineralised faster than SS. Yield was significantly higher (p < 0.05) in mineral fertiliser amended soil for the first crop whilst …