Dissanayake, D. K. R. P. L.Dassanayake, D. M. N. S.Udumann, S. S.Keerthisinghe, J. P.Jayalath, N.Idirisinghe, I. M. S. K.Silva, S.Gammanpila, J.Janaka, RDinesh, P.Atapattu, A. J2025-03-042023ISSPM-2023 (pp:143–156). National Institute of Plantation Management, Sri Lanka.https://dl-cri.nsf.gov.lk/handle/1/4295This study attempts to identify the optimum production conditions to produce ash using king coconut husk, providing a solution for the waste generated in the king coconut water processing industry in Sri Lanka. The suitable moisture content of the husk, the optimum cut size, and the dehydration period was determined by producing ash out of king coconut husk waste. Full, half, quarter, and chip cut sizes of husks were dried in a dehydrator at 60°C for different time periods (0h, 2h, 4h, 8h, 12h, 24h, and 48h). Twenty-eight treatment combinations were ashed in the muffle furnace at 600°C for 4h. The highest ash yield of 7.4 % was obtained from chips-sized particles dried over 24h that reached 2-4 % moisture. Therefore, chips are the most efficient particle size for drying king coconut husk, since they can achieve dryness within 24 hours at 60 °C in continuous drying. When the particle size is larger, it must be dried for 48 hours before being used in the production process. King coconut husk ash produced at the aforementioned optimum condition contained 26 ± 3 % of total K and 46.3 ± 6.01 % of total C pH, and EC of king coconut husk ash ranged from 10 – 11 and 10 μS/cm – 40 μS/cm, respectively. The chemical properties of king coconut husk ash are unaffected by particle size and drying time. However, husks with the lowest moisture content will produce more ash. King coconut husk ash is thus suitable for use for a variety of purposes, including as sustainable soil amendments.encoconut huskashoptimum cut sizeoptimum dehydrated timeking coconutArticle