Indigo is a plant that has a blue dye in it.Dyeing your hair is a fun way to make your hair the color that you want. Unfortunately, this can involve putting chemicals in your hair that irritate your scalp and skin. Dyeing your hair with indigo powder is a way to avoid this. Indigo powder is produced by grinding the leaves of the indigo plant, which means that indigo powder is completely natural. With indigo powder, you can make your hair as dark as you want without using chemicals.