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There is a need for an improved understanding of nitrogen (N) dynamics in depleted sandy soils in southern Africa. A field experiment was conducted to evaluate the performance of different soil fertility improvement practices on a degraded granitic sandy soil in Zimbabwe. Legumes capable of accumulating large amounts of N through biological N₂ fixation and subsoil N capture were tested against soybean/maize rotation, cattle manure fertilization and continuous maize (Zea mays L) with or without fertilizer. Soybean (Glycine max) accumulated 82kgha⁻¹N (seed+stover), while mucuna (Mucuna pruriens) produced 87kgha⁻¹N in its biomass. Soybean fixed 76% of its N, while mucuna fixed 96% of the accumulated N as estimated by the ¹⁵N natural abundance method. Although the following maize crop in the second season suffered from drought stress, maize N uptake was 14.8kgha⁻¹ following soybean and 16 …