The study was conducted to determine the optimum level of fertilizer for maximum yield of Amaranthus.A field experiment was conducted atFood and Agricultural Organization/ Tree Crop Programme (FAO/TCP) Teaching and Research Farm, Faculty of Agriculture, Adamawa State University, Mubi, Northern Guinea Savannah zone of Nigeria on sandy loam soil. This was to study the growth and yield of vegetable amaranth (Amaranathuscruentus L.) as influenced by row spacing and nitrogen fertilizer in 2015 and 2016rain fed cropping seasons. The experiment involved three levels of row spacing (20, 30, and 40 cm)and five levels of N fertilizer (0, 30, 60, 90, and 120 kg ha-1). These treatments in a factorial combination were laid out in a Randomized Complete Block Design and replicated three times. Data were collected on growth and yield parameters. Data generated were analyzed using Analysis Of Variance (ANOVA). Result show that Plant height, number of leaves, leaf area, absolute crop growth rate (plant-1) of vegetable amaranth increased significantly (P < 0.05) as row spacing and applied N rate was increased. On a unit of area basis however, fresh yield increased as the applied N increased and row spacing decreased. Application of higher dosage of fertilizer at the rate of 120 kg N ha-1 with narrow row spacing of 20 cm produced significantly higher fresh yield of 73.81 t ha-1 in 2015, 71.80 t ha-1 in 2016 and 72.81 t ha-1 combined. The least value of yield (14.7 t ha-1) was obtained in the treatment with wider row spacing and no application of N fertilizer (0 kg N ha-1 at 40 cm row spacing). Therefore, the optimum N rate and row spacing for the maximum yield of vegetable amaranth (Amaranthuscruentus L.) is 120 kg N ha-1 at 20 cm inter row spacing and was adjudged as the best combination for the production of vegetable amaranth in the Northern Guinea Savannah zone of Nigeria.
