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Pastures sown after several years cropping may take advantage of the residual lime and P fertilizers applied earlier. A field experiment was conducted to (i) compare the potential of different grasses to use previously applied P fertilizer at two levels of applied lime and (ii) evaluate the capacity of two soil tests to predict P availability to grasses. Four grasses [Andropogon gayanusvar. bisquamulatus (Hochst) Hack] cv. Planaltina; Panicum maximumcv. Makueni; P. maximumvar. trichoglume cv. Green panic and Setaria ancepscv. Kazungula were sown on an old experimental site where P fertilizers and lime have been applied over a period of 6 years for total rates of 0, 44, 87, 131, and 175 kg ha−1of P and 4 Mg ha−1of lime. Despite the well‐known P‐fixing capacity of the soil (clayey, kaolinitic, isohyperthermic, Typic Haplustox), grasses responded markedly to residual P and lime. Andropogon and to some extent Setaria performed better than the other grasses in both, limed and unlimed plots, at low levels of applied P. Makueni performed well only on limed plots at high levels of applied P (175 kg ha−1). Available soil P and dry matter yield correlated well but the range of P availability was too small for prediction purposes. It was concluded that despite high P‐fixing capacity a large portion of residual P remained available to grasses. Soil test procedures should be improved to better reflect the P availability to grasses.

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