Choosing what to plant depends on three factors: the local climate and rainfall pattern, the soil type already assessed, and realistic market demand for the harvest. Monocropping, growing a single crop across a field, simplifies management but concentrates risk, while intercropping, planting compatible crops together such as maize with cowpea, spreads risk and can improve soil fertility through nitrogen fixation from legumes. Crop rotation, changing what is planted in a given plot each season, breaks pest and disease cycles and prevents the soil from being depleted of the same nutrients year after year. In most of Nigeria's agroecological zones, the rainy season, roughly April to October in the south and shorter further north, defines the primary planting calendar for staples like maize, rice, and yam.