Also referred to as “Blue Gold” when it was first discovered, Indigo herb is an ancient Ayurvedic remedy for hair graying. Not only is it a natural hair dye, but also prevents or delays graying of hair when used earlier on. It can be easily mixed with henna powder to make a 100% natural hair dye that’s free from ammonia & other harmful substances. Even as a natural hair dye, it is found to last longer than other natural hair dyes.