An investigation was conducted during 2005, 2006 and 2007 wet seasons at the experimental farm of the institute of Agricultural Research, Samaru (11 o 11′N, 07 o 38′E, 686m above sea level) to study the effect of N, P and farmyard manure (FYM) rates on dry matter (DM) accumulation and uptake of cations by Roselle in the Northern Guinea Savanna agro-ecological zone of Nigeria. The experiment consisted of three levels of N (0, 60 and 120 kg N ha -1 ) in the form of urea, three levels of P (0,

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... and 26.4 kg P ha -1 ) in the form of single super phosphate (SSP) and three levels of FYM (0, 5 and 10 t ha -1 ). A total of twenty seven treatments were laid out in a split plot design with three replications. The factorial combinations of N and P were assigned to the main plots, while the FYM was allocated to the sub-plots. The result showed that application of 60 kg N and 5 t FYM ha -1 recorded significant increase in DM accumulation in Roselle, while applied P had no significant effect on DM production. Combined application of 120 kg N ha -1 with 5 t FYM ha -1 was optimum for DM production in Roselle. N application reduced K and Mg content but increased the uptake of the nutrients. Similarly, FYM reduced K and Ca content of shoots, while the uptake of these nutrients was increased by manure application. P application increased K and Mg, but reduced Ca contents of shoots. Application of P did not however exert significant effect (P<0.05) on the K and Mg uptake, but reduced Ca uptake of Roselle. Further trial of N application at higher rates is recommended in the study area.