FEEDBACK FRIDAY: This Week in Natural Dye Questions

This week: Lots of questions on the 1-2-3 Indigo Vat!

Every week, we are emailed with questions from our natural dye community asking simple and complex questions that we thought might be worth sharing. Of course, all of your burning questions are answered by natural dyer in chief, Kathy Hattori, Founder of Botanical Colors.

I was curious about the amount of water in the dye vat that you add the mason jar mixture to. Does it matter how much water is in there? You say 2/3 full, but what size is the dye vat?

The method that I am describing in our instructions has 2 steps. The first step is to create a stock solution of indigo in a Mason-sized jar. Many dyers feel that making a small concentrate allows the indigo and ingredients to react with each other more easily and encourage reduction. The second step is to make a vat with warm water and then add this concentrate, which becomes the indigo vat. However, a spoonful is a small amount of indigo, so your vat would be modest sized. If you want to make a large vat to dip a lot of fiber, your initial stock solution should be larger, and you can make it in a bucket. In order to figure out how much indigo to start, calculate the amount of fiber you have to dip, and how dark you want your indigo. For darkest shades, you would make a 1-2-3 stock solution of 6%, meaning 6 grams per 100 grams of fiber. A couple of pounds of fiber means that you would be making your initial stock with about 50 grams of indigo, 100 grams of calcium hydroxide and 150 grams of fructose. This is more than what fits into a Mason jar, so upgrade to a 3 gallon bucket for the stock solution, and use a 5 gallon bucket for the vat.

I just tried my first 1-2-3 vat, and I think I’ve run into a problem. I think I may not have mixed the fructose in well enough before adding the calcium hydroxide. Thus, my stock looks completely blue rather than greenish yellow. It seems like I didn’t reduce my indigo properly. Right now I’m letting the stick sit, but it’s still completely blue. Is there anything I can do to save it at this point?

Depending on how concentrated the stock solution is, the actual liquid can look quite dark. If you’ve waited and you have a flower and metallic skin on the surface of your jar, then you should proceed to create the vat. Mix the solution well and add to a container of warm water, which is your vat, and then observe. It should settle and start turning yellowish. If it does not, add more fructose, stir gently and wait.

Indigo really needs a few conditions in order to work, so if your vat looks completely blue, it needs to be reduced using fructose, henna, banana peels, or whatever your reducing ingredient is. If you’ve added reducing agent, stirred gently and waited a couple of hours and your liquid isn’t yellowish amber, brown, or green, then the vat may need a little bit of calcium hydroxide. Stir gently, let the liquid settle, and wait. Finally, if you really can’t tell if it’s working, try a test strip for 3 minutes in the bath and see if you can see oxidation and color development. If you can, then your vat should be fine.

I am used to using synthetic pre-reduced indigo, and I’d like to make the switch to natural indigo. If I do the 1-2-3 vat method without harsh chemicals, will this affect the results at all? For example, will the color be lighter, or will it be more difficult to get an even color? Or will the color fade faster than synthetic dye? I’m trying to get a better sense of how the end result will differ.

It will be different. Synthetic indigo is calibrated for very fast, dark coverage, with high percentages of indigotin. The 1-2-3 vat takes more effort and patience but yields a beautiful range of shades. Getting to a dark shade takes more work but the color is quite different than synthetic indigo in that it does have more variation and is more pleasing to the eye (that’s my opinion). Fading and discoloration can be the result of poor dipping, or sometimes ground level ozone, which is a pollutant that fades indigo.