Integrated nutrient management enhances productivity and soil and water conservation in a Brussels sprout–lettuce–broccoli rotation under acidic hill soils of the Western Ghats

Introduction Export-oriented vegetable cultivation in hill ecosystems requires nutrient management strategies that enhance crop productivity while maintaining soil health and minimizing environmental degradation. This study evaluated the effectiveness of integrated nutrient management (INM) practices in a Brussels sprout–lettuce–broccoli cropping sequence under the temperate conditions of the Nilgiris, Western Ghats, India. Methods A multi-year field experiment was conducted at the Indian Council of Agricultural Research (ICAR)–Indian Institute of Soil and Water Conservation, Research Centre, Udhagamandalam. Eleven nutrient management treatments were evaluated over three crop rotations for their effects on crop productivity, soil health, and soil and water conservation. The treatments included varying combinations of inorganic fertilizers, farmyard manure (FYM), bio-fertilizers, lime, and crop residue recycling. Results Pooled analysis indicated that INM-based treatments, namely T 5 (FYM 15 t ha −1 yr −1 + bio-fertilizers + lime + crop residue recycling), T 7 (75% NPK + FYM 3 t ha −1 yr −1 + other INM components as T 5 ), T9 (50% NPK + FYM 6 t ha −1 yr −1 + other INM components as T 5 ), and T 11 (25% NPK + FYM 9 t ha −1 yr −1 + other INM components as T 5 ), consistently outperformed the farmers’ practice (T 2 ). These treatments improved soil pH by 12.3–14.7%, reduced exchangeable Al by 32.5–38.2% and exchangeable acidity by 35.9–50.3%, and maintained 15.8–19.5% higher organic carbon levels than the farmers’ practice. Yield increases of 17.9–39.8% in Brussels sprout, 3.47–4.30-fold in lettuce, and 20.3–63.3% in broccoli were recorded under pooled conditions. In addition, selected INM treatments reduced runoff by 18.2–23.2% and soil loss by 22.2–39.2%, while achieving higher relative soil and water conservation efficiency (50.35–60.01%). Discussion and conclusion The findings demonstrate that INM-based nutrient management strategies improve soil quality, enhance crop productivity, and strengthen soil and water conservation compared with the prevailing farmers’ practice. Treatments T 5 , T 7 , T 9 , and T 11 are recommended, depending on FYM availability, as sustainable nutrient management options for vegetable cultivation in the fragile hill agro-ecosystems of the Western Ghats.