Alkanna tinctoria, the dyer's alkanet or alkanet, is a herb in the borage family. Its main notability is its roots are used as a red dye. The plant is also known as dyers' bugloss, orchanet, Spanish bugloss, or Languedoc bugloss. Alkanet grows in the Mediterranean region.
To get the gorgeous purple to red from the roots, the alkanet needs to be soaked in rubbing alcohol (or vodka) for a few days. Use dried alkanet at approximately 75-100% WOF for deep colours. When the alcohol has developed a strong colour, strain off the liquid and add enough water to cover your textile.
Add mordanted textiles or fibres (15% alum for protein, aluminium acetate for cellulose) and heat this dyebath no higher than 60ºC.
You can stop the dye process when the fabric has soaked up all the dye.