Objectives We investigated the current situation and regional characteristics in the fertilization of single-season rice production in Hubei Province, to evaluate the effect of the Implementation of Chemical Fertilizer Reduction and the Efficiency Increase Action, clarify the existing problems, and explore necessary solutions for the two actions in Hubei Province.

Methods In 2023, a questionnaire survey was conducted among 6,475 rice farmers in Hubei Province, using “one-to-one” and “face-to-face” survey methods. The survey covered a wide range of topics, including planting area, NPK fertilizer application amounts, types of fertilizers used, compound fertilizer formula for base fertilization, fertilization frequency and methods, as well as yield and other relevant data. Subsequently, the application proportions and amounts of N, P, and K fertilizers, the yield, and fertilizer utilization efficiencies were calculated on a regional scale across Hubei Province.

Results In Hubei Province, the N and P₂O₅ input levels for one-crop mid-season rice were considered relatively reasonable, averaging 170.1 kg/hm² and 63.0 kg/hm², respectively. However, the K₂O input, averaging 81.2 kg/hm², exceeded the recommended levels and could potentially be reduced. In southeastern Hubei, a significant proportion of farmers applied insufficient amounts of N and P fertilizers (49.9% for N and 39.5% for P fertilizer), while 59.6% applied excessive K fertilizers. In the central and northern regions, 41.3% and 39.1% of farmers applied insufficient N and P fertilizers, and 59.4% applied excessive K fertilizers. In the Jianghan Plain, 32.3% and 52.1% of farmers applied excessive N and K fertilizers, respectively, while 55.9% applied insufficient P fertilizers. Western Hubei saw a particularly high rate (66.8%) of insufficient P application. The survey of fertilizer types revealed that 95.9% of rice farmers opted for compound fertilizers as base fertilizer, followed by organic fertilizers (36.2%). When it comes to topdressing, 56.1% of farmers chose urea, with compound fertilizer as the second choice (22.0%). The formulas of N, P, and K in base-applied compound fertilizers were notably diverse. Fertilization frequency was mainly twice per season (70.2%), followed by once (15.0%).

Conclusions The efforts to reduce chemical fertilizer use and enhance efficiency in one-season mid-season rice cultivation in Hubei Province have yielded remarkable results. The input of N and P₂O₅ nutrients is well-balanced, while there is room for reducing K₂O inputs. Significant regional variations in nutrient inputs were observed. Therefore, it is suggested that slow-release fertilizers tailored to rice cultivation should be developed based on the regional characteristics. Additionally, the wide adoption of mechanical side-deep fertilization technology is encouraged to further reduce chemical fertilizer use and promote the green and sustainable development of rice cultivation.