How did the dark green ancients dye cloth?

In ancient China, the dyes used for dyeing were mostly natural minerals or plant dyes, and plant dyes were the most commonly used in natural dyeing. Such as bark, roots, branches and leaves, fruits and shells; Flowers, dried flowers, flowers and leaves, flowers and fruits; Fruit peels, fruits, fruit juices, herbs, Chinese medicines, tea and many others can be used for dyeing. Using plant dyes is the mainstream of ancient dyeing technology in China. Dark green is the plant dye used, and the most famous is the blue grass blend. The dyeing processes created by the ancients according to different dye characteristics include direct dyeing, mordant dyeing, vat dyeing, resist dyeing and overprint dyeing. With the continuous improvement and development of dyeing technology, the ancients in China have been able to use dark green fabrics dyed with plant dyes.