Magnetic irrigation water was studied at the research farm in Kwara State University, Malete on the growth and yield of cowpea cultivar TVX-117 under transparent garden. Water was passed hrough 112.74 mT magnetic flux twice and ordinary water served as control treatment. Cowpea seeds were planted in buckets replicated 10 times using Randomized Complete Block Design (RCBD). Irrigation interval of 3-day and 1.50 litres of water as volume of water required for two stands of cowpea were experimented. Magnetic fields changed the physicochemical properties of water and results obtained indicated significant differences in seeds germination, crop height, stem diameter and cowpea yield compared to control treatment of non-magnetized irrigation water at P< 0.05 significant level. Magnetic agriculture is environmentally friendly, no health implications on consumption of produce and reduces cost of production.