Field experiments were carried out during the 2000 and 2001 rainy seasons on the field of National Horticultural Research Institute at Bagauda (latitude 11o 33’ N and longitude 8o 23’E of the equator). The experiment was aimed at evaluating the response of roselle cultivars to different levels of N in combination with 50 kg P/ha and establishing an
optimum N fertilizer requirement by roselle. Five rates of nitrogen (0, 30, 60, 90 and 120 kg N ha-1) were combined with deep red and pure white cultivars of roselle in a randomized complete block design arrangement with three replications. Application of N significantly (p < 0.05) increased plant height, number of leaves, branches, pods, calyx and seed yields
o roselle. Application of 50 kg P/ha as basal dressing significantly (p < 0.05) influenced the production of calyces among the cultivars. In Nothern Guinea savanna, calyx yield of 2.38 t/ha fresh weight with a corresponding dry matter of 1.02 t/ha were significantly different (p < 0.05) when 30 kg N/ha was applied to deep red cultivar and second season (2001) was better than the first season (2000). Similarly, significantly differences (p