Increasing the Growth and Production of Shallots by Giving Tithonia Liquid Organic Fertilizer and Biosaka

Abstract Shallots are an important vegetable commodity cultivated intensively by farmers, yet organic shallot production remains limited. Continuous use of chemical fertilizers causes soil degradation and decreases shallot quality. Organic fertilizers can restore soil fertility and support sustainable farming. Tithonia diversifolia , a wild plant, can be processed into liquid organic fertilizer (LOF) containing essential nutrients; after nine days of fermentation, it yields a nitrogen content of 1.46%. Meanwhile, Biosaka , a natural extract from various weeds, functions as a biological elicitor that enhances plant resistance and productivity, especially under organic cultivation. This research want to evaluate how Tithonia LOF and Biosaka affect the growth and yield of shallots. The experiment was conducted in Medan, North Sumatra, from January to March 2025, arrange in randomized complete block design with two treatments: Tithonia LOF doses (0, 200, 400, 600 ml/polybag) and Biosaka concentrations (0.0, 1.3, 2.6, 4.0 ml/L). The research data were analyzed using the DMRT at 5%. The research results that Tithonia LOF up to 600 ml/polybag significantly improved shallot growth and yield, while Biosaka and its interaction with Tithonia LOF showed insignificant effect on all parameters.