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The major challenge of most legume-based soil fertility improving technologies lies largely at ensuring high legume biomass productivity on soils of low inherent fertility. We evaluated biomass productivity of indigenous legumes on fields which had been abandoned by farmers due to poor fertility under low (450-650 mm year^-1) to high (>800 mm year^-1) rainfall areas of Zimbabwe, in the 2004/05 and 2005/06 rainfall seasons. The fields had <14% clay, <5 ppm available P and <0.5% organic C. Legume species, mostly of the genera Crotalaria, Indigofera and Tephrosia were sown in mixtures based on knowledge from previous studies. Indigenous legume fallows (indifallows) produced 4, 7 and 15 t ha^-1 of biomass under low, medium and high rainfall, respectively, within six months. Indigenous legumes contributed 70-90% of the biomass on dry matter basis. Natural fallows yielded 1-4 t ha^-1 of biomass across …