Effects of Organic Growing Media on Growth, Yield and Bioactive Compound of Black Ginger (Kaempferia parviflora) Cultivated using Soilless Culture

The experiment, conducted under a side-netted rain shelter, holds promise for the future of black ginger cultivation. Five mixtures of organic growing media were evaluated: 100% coco peat; 100% rice husk ash; 70% coco peat + 30% rice husk ash; 30% coco peat + 70% rice husk ash; and 50% coco peat + 50% rice husk ash. The black ginger rhizomes were harvested eight months after planting. The plants grown in 50% coco peat + 50% rice husk ash mixtures showed the best growth performance and yield, producing the highest vegetative fresh weight shoot height (678 g) and rhizome yield (582 g per plant). The lowest rhizome yield (154 g) was obtained from plants planted in 100% coco peat. However, plants cultivated in 100% coco peat gave rise to the highest 4,5,7-trimethoxyflavone compared to the other samples. Therefore, the black ginger plants cultivated in 50% coco peat + 50% rice husk ash mixtures growing media using a soilless culture system demonstrated the best plant growth and yields. However, 100% coco peat growing media should be considered to achieve the highest 4,5,7-trimethoxyflavone accumulation in black ginger rhizomes, opening up new possibilities for the future of black ginger cultivation.