Which policy options are more effective in promoting the green development of family farms within the framework of coordinated development?

Enhancing the effectiveness of green agricultural policies is critical to promoting agricultural green development in China, where family farms are an important force in environmentally friendly production. Using monitoring data from nearly 2,000 planting-oriented family farms, we construct a system dynamics model integrated with a coupling coordination framework to evaluate how major green policy instruments and their combinations influence the green development level (GDL) and subsystem coordination. Focusing on the period 2014–2030, we conduct policy simulations involving five policy instruments: land transfer policy, green credit policy, green subsidy policy, green technology training, and standardized management policy. The results indicate that the green subsidy policy is the most efficacious single policy in enhancing the GDL, with a relative impact of 9.58% compared to the baseline scenario, while the green credit policy and standardized management policy play a more distinguished part in improving system coordination. Simultaneously bolstering multiple policies increases the GDL of family farms, but at the cost of eroding coordination between subsystems. A phased policy strategy—deploying green subsidies in the early stage and strengthening green credit and standardized management in the later stage—raises the GDL by 8.43% relative to the baseline scenario while preserving higher subsystem coordination. These findings point to the necessity of sequencing green agricultural policies across different stages of development, rather than intensifying them concurrently across the board, with policy-relevant implications for fostering the coordinated green development of family farms in China and other developing economies.