ORGANIC SOIL AMENDMENT AS SUSTAINABLE ALTERNATIVE FOR TOMATO (Solanum lycopersicum) GROWTH

Abstract

The increasing cost and environmental impact of synthetic fertilizers have prompted growing interest in sustainable and cost-effective alternatives in educational and community-based agriculture. This study investigated the effectiveness of an organic soil amendment composed of equal parts cocopeat, wood shavings, rice hull, and charcoal on the growth performance of tomato (Solanum lycopersicum) plants and soil nutrient quality, as compared to commercial fertilizer. Conducted at Zamboanga del Norte National High School–Turno under the Gulayan sa Paaralan framework, the research used a quantitative posttest-only control group design with 30 tomato plants randomly assigned to two treatments. After 11 weeks, results showed that the organically treated plants achieved comparable stem height, leaf development, and fruit yield to the commercial fertilizer group, with no statistically significant differences (p > .05). Soil analysis revealed that the organic mixture had high phosphorus, sufficient potassium, and near-neutral pH levels, suitable for tomato cultivation despite low nitrogen content. These findings support the potential of agricultural waste-derived compost as a viable, sustainable alternative to synthetic fertilizers, aligning with the Organic Agriculture Act of 2010 (RA 10068), DepEd’s school garden program, and the United Nations Sustainable Development Goals. The study provides a replicable model for promoting sustainability, environmental education, and food security in public schools and rural communities.