Effects of Cultivation Factors on Indigo Dye Yield in Indigofera Plants

This research investigated the local wisdom of Sakon Nakhon province, Thailand, on cultivating Indigofera plants for optimal natural indigo dye yield. Focusing on Indigofera suffruticosa Mill. and Indigofera tinctoria L., the study explored the impact of pod development stages and harvesting time on dye yield. The findings showed that harvesting at the brown pod stage (18 - 20 weeks) and early morning (6:00 a.m.) yielded the most dye. Additionally, the study compared the Indigofera plants cultivation under 100 % and 60 % sunlight exposure, demonstrating that full sunlight significantly increased dye yield. Moreover, Indigofera suffruticosa Mill. gave significantly more indigo dye yield than Indigofera tinctoria L. (p < 0.05). This investigation, therefore, underscores the value of incorporating local knowledge into optimal cultivation practices for enhanced indigo production. However, further research should delve into additional factors, such as soil composition, fertilizer regimes and the genetics of the Indigofera plant. HIGHLIGHTS This research investigates factors affecting natural indigo dye yield in Indigofera suffruticosa Mill. and Indigofera tinctoria L., the dominant species in Sakon Nakhon province, Thailand. Integrating local knowledge with multidisciplinary research, the study advances natural indigo dye production, offering insights for optimizing yield and promoting sustainable practices. This collaboration enriches understanding and fosters innovative Indigofera cultivation methods, marking a significant step forward in the field.