Here are the ingredients needed to start an indigo fermentation vat. During the summer months my vat stays outside. In the winter when I want to use it, I place it in a box near my wood stove. I also use a clip on light with a 100 watt bulb . The fermentation process needs heat to work properly (About 100 degrees). Proportions for the ingredients–
4 ounces ground indigo
2 ounces madder root (ground)
2 ounces wheat bran
12 ounces soda ash (sodium carbonate)
Weigh ingredients and place in a bucket full of warm water.
Alpacas do like to supervise!
Stir all ingredients to combine. Now let it sit for about a week. Stir daily but make sure to stir slowly. You do not want to introduce oxygen in to your vat. Fill bucket to within 2 inches of the top. If your temperatures were warm enough, within a week your vat will have a shiny coppery look on top and a dull yellowish color liquid. Perfect!. Add wetted fibers and dye!
To reconstitute your vat just add the ingredients and start the process over.
Some variegated indigo dyed alpaca.