Indigo (natural) – natural indigo powder is an extract prepared from Indigofera tinctoria which is cultivated for this purpose. Indigo is the legendary source of colourfast blues and its ability to produce a wide range of shades has made it the most successful dye plant ever known. Indigo grows all over the world but flourishes best in hot, sunny, humid areas. Indigo can give clear blues that range from the tint of a pale sky to a deep navy that is almost black. Maiwa's indigo comes from a farm in south India and is very strong (approx. 40% indigotin). It reduces beautifully in an indigo vat.