Optimal fertilization schedules provide yield and quality in cabbage: Insights from a global dose–response meta-analysis

• Comprehensive global meta-analysis of cabbage fertilization synthesizes 342 field trials, revealing potassium's unique ability to break the yield-quality trade-off paradigm. • Different traits require distinct fertilization frequencies: single head mass optimizes with single applications, yield peaks at 2–3 applications, while head height needs 3–4 applications. • Optimal fertilization timing occurs 15–21 days after transplanting, with N/K ratio of 1.83 maximizing yield and 1.0 optimizing quality parameters. The conventional nitrogen-centric paradigm in vegetable fertilization creates a persistent yield-quality trade-off that constrains sustainable intensification. We present a comprehensive meta-analysis of 342 field trials examining cabbage ( Brassica oleracea var. capitata L. ) responses to six fertilization management factors across global production regions. We evaluated nitrogen application rate, phosphorus application rate potassium application rate (KFR), first application timing of top-dressing, total fertilization applications, and nitrogen/potassium ratio effects on yield, single head mass, soluble sugar content, plant height, and cabbage head height. Quadratic dose-response modeling revealed that KFR effectively addresses the yield-quality trade-off, at optimal rates of 117–127 kg K 2 O ha −1 , KFR significantly enhanced yield (+32.82 %, CI: 30.17–37.31 %), single head mass (+25.46 %, CI: 14.62–34.87 %), while maintaining positive effects across all measured traits. In contrast, nitrogen increased yield (+29.17 %) but reduced soluble sugar content (-4.34 %). Trait-specific fertilization frequency preferences emerged: single head mass optimized with single applications, yield maximized at 2–3 applications, while head height required 3–4 applications. Optimal timing occurred 15–21 days after transplanting. The N/K 2 O ratio critically influenced outcomes, with yield peaking at 1.83 and quality parameters optimizing near 1.0. Model fit was consistently high (R 2 > 0.85 for principal traits), and all effects were statistically significant ( P < 0.001, based on 95 % confidence intervals from random-effects meta-analysis). These findings demonstrate that potassium-centered fertilization strategies, rather than conventional nitrogen-centric approaches, enable simultaneous yield and quality optimization in intensive cabbage production systems, providing quantitative frameworks for precision nutrient management under resource constraints.