Structural, climatic, and cost drivers of wheat production in South Africa: an ARDL analysis (1990–2022)

This study investigates the main structural, climatic, and cost-related determinants of wheat production in South Africa, with the objective of identifying the dominant long-run and short-run constraints shaping domestic supply. Annual data for the period 1990–2022 are analyzed using an Autoregressive Distributed Lag (ARDL) model with an error-correction specification to capture both equilibrium relationships and adjustment dynamics between wheat output, cultivated area, fertilizer use, input price inflation, and rainfall variability. The results confirm a stable long-run cointegrating relationship among the variables. Cultivated area is the most influential long-run driver of wheat production, followed by rainfall, while input cost inflation exerts a statistically significant and economically negative effect on output. Fertilizer use is significant but displays a small elasticity, indicating limited marginal productivity under prevailing structural and climatic conditions. The error-correction term indicates moderate adjustment toward long-run equilibrium, reflecting rigidity in land allocation and input procurement. These findings imply that policies focused solely on input intensification are insufficient to stabilize wheat production. Instead, policy efforts should prioritize land-use incentives, reduced exposure to input price volatility, and improved climate-risk management to enhance long-term production resilience and food security.