OICC Press International Journal of Recycling of Organic Waste in Agriculture 2251-7715 15 3 2026 09 30 Effects of Water Hyacinth Compost on Growth of Rhodomyrtus Tomentosa (Aiton) Hassk. and Rhodomyrtone Yield 10.57647/ijrowa.2026.1503.24 EN Sara Bumrungsri Division of Biological Science, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand Unitsa Sangket Division of Biological Science, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand Supayang P. Voravuthikunchai Natural Product Research Center of Excellence, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand; Center of Antimicrobial Biomaterial Innovation-Southeast Asia and Natural Product Research Center of Excellence, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand Aunkamol Kumngen Division of Biological Science, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand Noodchanath Kongchouy Division of Computation Science, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand Jutarut Iewkittayakorn Division of Biological Science, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand; Center for Genomics and Bioinformatics Research, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand Journal Article 2026 09 30 Purpose: Water hyacinth (WH) is an aquatic weed that has negatively impacted aquatic ecosystems. WH can be easily composted and used as a soil ameliorant to improve plant growth. In this study, the effects of WH compost on the growth of Rhodomyrtus tomentosa were evaluated. Methods: Native R. tomentosa seedlings were cultivated with WH compost in two different systems: a pot cultivation with soil: WH compost mixed in ratios ranging from 10:0 to 7:3 and an open field cultivation with 1 to 3 parts of WH added to the topsoil. Plant growth characteristics and rhodomyrtone yield were also investigated. Results: Plant height and numbers of stems were not significantly different between the two cultivation methods (p>0.05). Plants treated with WH compost had more leaves than those not treated with WH compost (p<0.05). Growing the plants with WH compost resulted in significant increases in leaf biomass, especially, rhodomyrtone content in both cultivation systems. In the pot cultivation system, the highest rhodomyrtone yield (0.99 mg/mL) was obtained from R. tomentosa leaf from plants growing in a soil and coconut coir medium enriched with 1 part of WH compost by volume. In the field cultivation system, the highest rhodomyrtone yield (0.86 mg/mL) was obtained from R. tomentosa leaf sampling from plants growing in soil with 1 part of WH  added to the soil at the planting period and once every month. Conclusion: WH compost demonstrated its potential for sustainable cultivation of R. tomentosa that can be fruitfully propagated for commercial purposes.