Agronomic considerations for urban agriculture in southern cities.

Urban and peri-urban agriculture (UA) provide a significant contribution to the total food requirements of cities, especially in southern cities of the developing world. Increasing food production in UA is therefore a necessity for increasing the food security of the urban poor. Urban environments are inherently different from rural environments and these differences in environmental conditions are expected to impact differently on crop growth. This review describes agronomic issues that are unique to UA and identifies possible interventions to address them. The constraints that can significantly differ include temperature, air quality, solar radiation and climate. The growth-limiting and growth-reducing factors that affect actual production in UA include water availability, nutrient supply, soil degradation, pests and soil pollution. The interventions addressing these constraints require action at both field level, and municipal or regional levels. The food security of the urban poor will therefore requi...