Abstract: Background and Objective: The production of maize field biomass and Stover is enhanced by inclusion of legume in cropping system. The objective of the study was to determine the effects of cropping system, nitrogen fertilizer, planting season and location on maize field biomass, Stover yield and land equivalent ratio. Materials and Methods: A factorial experiment randomized in complete block design with three replications was conducted during 2011/12 and 2012/13 planting seasons. The experiment comprised of three cropping systems which were cowpea-maize rotation, monocropping maize and intercropped maize. The experiment was conducted at three environmentally different locations (Potchefstroom, Taung and Rustenburg). Two rates of nitrogen fertilizer were applied in kg ha–1 at each location (0 and 95 at Potchefstroom, 0 and 92 at Rustenburg, 0 and 113.5 at Taung). Measured parameters were plant population at harvest, field biomass, Stover yield and land equivalent ratio. Results: Planting season had significant effect on plant population at harvest, field biomass and Stover yield. Maize harvested during 2012/13 planting season had significantly higher plant population, field biomass and Stover yield than during 2011/12 planting season. The interaction of location×nitrogen fertilizer×plant season had significant effect on plant population at harvest and maize Stover yield. Total LER was found to be higher than 1.0 showing the advantage of intercropping over sole stand. Conclusion: Maize field biomass, Stover yield and LER depend on planting season and location.