Role of vermicompost and biostimulants in enhancing garlic growth, bulb yield, and quality parameters

Organic fertilizers and biostimulants have been widely studied in vegetable crops, but evidence on their individual and combined effects on growth and quality remains limited. Therefore, this study assessed the effectiveness and synergistic potential of selected organic amendments and biostimulants in improving garlic growth, nutrient composition, allicin content, and total yield. Across two growing seasons, garlic plants received the followed treatment: 1) seaweed extract (SW), 2) garlic extract (GE), 3) yeast extract (YE), 4) vermicompost (VC), biochar, and their combinations. Growth traits, nutrient concentrations, allicin content, bulb characteristics, and yield components were measured and compared with an untreated control. All treatments significantly enhanced plant height, leaf number, and leaf area. The co-application of GE + SW along with vermicompost and biochare produced the highest growth performance and nutrient accumulation. Furthermore, this treatment also markedly increased allicin content, improving bulb quality, and resulted in the greatest bulb weight and total yield. Overall, combining organic fertilizers with biostimulants provides a sustainable strategy to enhance garlic productivity and quality while reducing dependence on synthetic inputs. The study recommends the integrated use of GE + SW with vermicompost and biochar as an effective nutrient management approach.