Journal of Experimental Agriculture International

The field experiment was conducted during the 2019 rainy season at the Teaching and Research Farm of the Centre for Dryland Agriculture (CDA), Bayero University, Kano, Nigeria (Latitude 11⁰58’N and Longitude 8⁰26’) and the Training and Research Farm of Kano University of Science and Technology, Wudil located at Gaya to evaluate the response of Roselle to NPK fertilizer and stand densities on calyx yield. The treatments consisted of five levels of NPK fertilizer (0, 80, 100, 120, and 140 kg/ha) and four stand densities (2, 3, 4, and 5 plants/hill), which were laid out in a randomized complete block design (RCBD) with three replications. Data was collected on plant height, the number of leaves per plant, leaf area per plant, and the number of branches per plant. These were subjected to analysis of variance (ANOVA) using GenStat 17^th Edition and the means were separated using the Duncan Multiple Range Test (DMRT). The result showed that the stand density of 5 plants/stand significantly produced the tallest plants. The result also showed that the application of different NPK levels had a significant (P<0.05) effect on plant height, the number of leaves, and the leaf area of Roselle across the two experimental sites. The highest values of plant height, number of leaves, leaf area, and number of branches were influenced by the application of 140 kg/ha of NPK at both locations. The control plots recorded the lowest values for all the characters studied. Based on these findings, 5 plants/stand and application of 140 kg/ha NPK fertilizers are recommended.