Tackling climate risk to sustainably intensify smallholder maize farming systems in southern Africa

Abstract Sustainable intensification (SI) of low input farming systems is promoted as a strategy to improve smallholder farmer food security in southern Africa. Using the Limpopo province South Africa case study (four villages across climate gradient), we combined survey data (140 households) and quantitative agronomic observations understand climate-induced limitations for SI maize-based systems. Insights were used benchmark agroecosystem model Agricultural Production System sIMulator, which was setup ex ante evaluate technology packages (TPs) over 21-seasons (1998–2019): TP0 status quo (no input, broadcast sowing), TP1 fertiliser (micro dosing), TP2 planting density (recommended), TP3 weeding (all removed), TP4 irrigation, TP5 date (early, recommended), TP6 all (TPs 1–5). An additional TP7 (forecasting) investigated varying line with weather forecasts. Input intensity levels expressed similar challenges risk adaptation, strategies mostly limited adjusted dates densities, less than 2% farmers having access water irrigation. Simulations showed that combining management interventions would be expected lead highest mean maize grain yields (3200 kg ha −1 villages) lowest harvest failure compared individual interventions. Likewise, simulations suggested irrigation alone not result yield gains simple adjustments forecasts indicated could expect turn rainfall variability into an opportunity well worth taking advantage of. Our emphasises need cropping approach addresses multiple crop stresses simultaneously.