Growth Response of Water Spinach to Liquid Organic Fertilizer from Fruit Waste

Abstract

Farmers' continuous reliance on chemical fertilizers can degrade soil quality over time, while abundant fruit waste remains underutilized. This study aimed to determine the effect of liquid organic fertilizer (LOF) derived from mixed fruit waste on the growth of water spinach (Ipomoea aquatica Forsk.) and to identify the most effective concentration. A Completely Randomized Design was employed with four LOF concentration levels (0%, 10%, 20%, 30%), each replicated three times. The parameters observed were plant height, leaf number, and fresh weight, analyzed using Analysis of Variance (ANOVA) followed by a Least Significant Difference (LSD) test at the 5% level. The results showed that LOF significantly affected plant height at 14 and 28 days after planting, with the 30% concentration producing the tallest plants (25.33 cm), significantly different from the other treatments (18.83–20.17 cm). However, LOF had no significant effect on leaf number or fresh weight. The continuously increasing response up to the highest concentration tested suggests that the optimum point lies above 30%, consistent with hormesis theory. This study concludes that mixed fruit-waste LOF has potential as an alternative organic fertilizer to promote plant height growth in water spinach, although further research with a larger number of replications is needed to confirm its effect on other growth parameters.