What plant was grown for blue dye in colonial times?

In colonial times, the plant commonly grown for blue dye was indigo (Indigofera tinctoria). This plant's leaves were fermented to produce a deep blue dye, which became a valuable commodity in the textile industry. Indigo cultivation was particularly prominent in the southern colonies, where the warm climate was conducive to its growth. The dye was widely used to color fabrics and was highly sought after in both domestic and international markets.