Surfing the web I found this interesting collection of plants, used to dye fabrics:
Alkanet: Alkanna tinctoria family Boraginaceae with a bright blue flower, used to provide a red dye.
Annatto: Bixa orellana A yellow dye. The plant is also grown for ornament or hedging and used medicinally.
Brazilwood: Caesalpinia echinata A species of Brazilian timber tree in the Fabaceae family. This plant has a dense, orange-red heartwood that yields a red dye.
Henna: Lawsonia inermis Most commonly used for temporary decorative tattoos.
Indigo: Indigofera tinctoria several species of the same genus were once of international importance as the source of the blue-black dye indigo.
Kamala: Nelumbo nucifera more commonly referred to as the lotus, is the national flower of India and Vietnam
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