Refining fertilizer formation policy for optimal nitrogen and phosphorus application

Environmental policies are a common means to reduce the impact of nitrogen (N) and phosphorus (P) fertilizers on the environment. This case study investigates the fertilizer formation policy (FFP) associated with N and P management in China. The results from a farmer survey ( n = 183) showed 12.8% increase in FFP adoption overall, with adoption rising by 16.4% in cereal and oil crop farms but remaining unchanged in cash crop farms. The FFP resulted in an 8.7 kg P 2 O 5 ha −1 decrease in the application of surplus P without obvious effect on farm revenues; however, the N surplus unexpectedly increased by 7.9 kg N ha −1 . This swapping was attributed to the higher N:P ratio of formulated fertilizers compared to traditional compound fertilizers, as well as the unchanged physical fertilizer dosage. Scenario analyses indicate that even if farmers adopt formulated fertilizer at recommended dosages, the issue of N and P swapping remains. To achieve greater improvement of nutrient use efficiency, more precise fertilizer formulas are needed. Additionally, farmers need to be encouraged to adopt best management practices. This includes conducting conversation‐based promotion, diversification of formulated fertilizer products, enhancing economic incentives, and multi‐stakeholder collaboration. In conclusion, these findings provide critical insights for improving both N and P management and practical improvement in promoting the widespread adoption of formulated fertilization practices.