I’m redoing my indigo fermentation vat this weekend. It’s been a while in coming. I emptied it out (25-30 gallons) about 2 months ago when I was redoing a fence line that it sat along and it needed to be moved. At the time I was also having some issues with fruit fly larva in the vat and wanted to have a fresh start and see if I could solve that issue.
The vat will take at least a week to ferment to a usable state and in addition I need to receive an order of ground indigo from Cheryl at Aurora Silks. Coincidentally, she is having a sale on the 1 Kilo size ground natural indigo and offers free shipping. I only had 4 oz on hand so made the vat up with that to get it started and will add the rest of the indigo when it arrives in a couple of days.
I am adding a fine mesh cover to the top of the vat since the lid to this container is not a complete seal. Additionally, I am making a large net bag to drop into the vat while dyeing to keep all the organic materials and sludge to the bottom and away from the cloth as I work. It’s really only an issue when working with larger open weave fabrics which I seem to use a lot these days. It saves having to pick out the particles by hand or resort to lots of water wasting rinsing. Water is precious here.
When I disposed of the old vat I balanced the ph with some citric acid down to about 7 and used the liquid on the ornamental drought tolerant landscaping. The rest of the sludge in the bottom I added to the compost and was ready to start again. This vat had been in use for 4-5 years.
I am adding some video of the process of this new vat to the student forum for the online indigo workshop I have in my shop. Here is a little bit of day two progress…
August 6-7 is the final summer indigo workshop at the Japanese American National Museum. Signups are through the museum here.
Last time this is some of what participants did…