keywords: Economic returns, fertilizer rate, Kafanchan, sowing date, watermelon
A field experiment was conducted between September and December, 2015, in two sites at Katsit, suburb of Kafanchan, Jema’a Local Government area of Kaduna State, Nigeria. The experiment was aimed at determining the appropriate planting date and nitrogen rate for optimum watermelon (Citrullus lanatus Thumb) yield, quality and realisable revenue in the study area. The treatments consisted of three planting dates with four levels of nitrogen fertilizer and a control fitted in a Randomized Complete Block Design, replicated three times. Data collected were subjected to analysis of variance; means of treatments significantly different were separated using Duncan Multiple Range Test at 5% level of significance. Economic returns were analyzed using the Gross margin. The results showed that there were significant difference among the treatments in number of fruits and yield per hectare. However, watermelons sown in the middle of September at 30 kg N ha-1 fertilizer level gave the highest yield of 36,000 kg ha-1 and also gave the highest gross margin of N180, 967.00 ha-1. It is therefore recommended that farmers in the study area should plant watermelon in the second week of September and to apply 30 kg N ha-1 of fertilizer in order to make optimum profit.