Indigo powder is a natural colorant made from the dried leaves of the Indigofera tinctoria plant, which grows in Asia and parts of Africa. Though green in its dry form, it turns deep blue when exposed to air after mixing with water. Traditionally used for dyeing cotton, wool, and silk, its also applied in natural hair coloring, often alongside henna. Free from synthetic dyes, indigo powder is typically mixed into a paste for use in textile and personal care routines.