o:9843 Alfalfa as a Biological Nitrogen Source and Biofertilizer Component in Sustainable Horticultural Production Systems en Abstract: Alfalfa (Medicago sativa L.) is widely recognized as a major forage crop, yet its role as a multifunctional biological input in sustainable horticultural production remains underexplored. This review evaluates alfalfa as a biological nitrogen source, organic fertilization resource, and biofertilizer-supporting crop within vegetable, medicinal, and perennial horticultural systems. Due to its high capacity for biological nitrogen fixation, alfalfa can supply substantial amounts of plant-available nitrogen, reducing dependency on synthetic fertilizers and supporting environmentally sound nutrient management. When used as green manure, cover crop, intercrop, mulch source, compost feedstock, or processed organic fertilizer, alfalfa enhances the soil organic carbon (SOC), improves soil structure, and increases the water-holding capacity properties particularly critical in intensive horticultural production. Higher SOC levels also contribute to the improved tolerance of horticultural crops to drought and heat stress through enhanced soil moisture retention and rhizosphere buffering. Alfalfa-based organic inputs stimulate rhizosphere microbial biomass, enzymatic activity, and functional genes associated with nitrogen cycling, strengthening plant–microbe interactions that underpin biofertilizer effectiveness. Evidence from vegetable and perennial systems indicates that alfalfaderived amendments and rotations increase soil nitrogen availability, support yield stability, and improve soil health over the long-term. In orchards and vineyards, alfalfa cover cropping contributes to carbon sequestration, erosion control, and enhanced soil biological functioning. Overall, alfalfa emerges as a strategic species for integrating organic fertilization and biofertilizer-based approaches into modern horticultural systems, supporting reduced mineral fertilizer inputs while sustaining productivity, soil health, and environmental quality. alfalfa (Medicago sativa L.); organic fertilization; biofertilizers; biological nitrogen fixation; green manure; soil organic carbon; soil health; nutrient cycling; sustainable horticulture; cover cropping; climate-resilient horticulture 1552099 10.3390/horticulturae12060740 2026-06-18T12:27:15.227Z 44 no 46 Vladimir Filipović 46 Elmira Saljnikov 46 Snežana Dimitrijević 46 Ljubica Šarčević-Todosijević 46 Vera Popović 46 Aleksandar Miletić 46 Jelena Golijan Pantović 46 Aleksandra Stanojković-Sebić Institute of Soil Science 0000-0002-5176-9827 46 Vladan Ugrenović Institute of Soil Science 0000-0001-6642-8235 application/pdf 1635502 https://unilib.phaidrabg.rs/o:9843 no yes 1 70 92000002 71A05 Horticulturae 2026