Indigo Afternoon

Making my first successful Vat

Natural Dye

Dyeing with indigo is spoken about with such reverence in the natural dye world so it was only after 20 other natural dye experiments that I felt ready to take it on. After doing it once, I'm actually not sure it was that more intense than other experiments, all things considered. Unlike the rest of the natural dyes I've concocted, indigo does not require the rigorous steps to prepare fabric for dye that others do (mordanting, tannin dyeing, chalking), only scouring. Additionally, fabric only needs to be dipped in the vat for 10-20 minutes, rather than as long as a week in other projects I've done. However, the process to make the vat was definitely more involved than just simmering some flowers for a while.

I'm certainly not an expert about the science behind indigo dyeing, but at a super high level, the reason the vat takes some doing is that indigo dye in powder form like the stuff I ordered from Maiwa is not water soluble, so you have to "reduce" it, or get it to chemically bind with the water molecules, before you can dip your fabric. In order for reduction to happen, you must have a reducing agent and sufficiently alkaline water. There are many ways for meet that criteria but for this vat, I followed Maiwa's instructions for a Fructose Vat, using fructose as my reducing agent and calx as a base to bring up the pH of my water.

Once the indigo vat has been reduced, it forms three distinct layers — the top looks unnaturally metallic and blue, the middle (largest) layer is a sort of pee-yellow or "leuco-indigo" solution of reduced indigo, and the bottom a layer of unreduced sediment. The goal is to submerge the item into the leuco-indigo layer, not to touch the sediment on the bottom, and to introduce as little oxygen which will undo the reduction as possible. After 10-20 minutes, you carefully remove the item and watch the magical transformation from yellowish green to turquoise to indigo blue!

Because this dye experiment felt like such a stepping stone for my natural dye skills, I invited my friends May and Nick over to dye some of their own stuff and to document and celebrate the process on a beautifully warm early fall day. Whereas I just had some cotton and linen fabrics and thread, Nick brough shoes and May brought some white graphic t's which were fun to play with.

Indigo won't penetrate folds and creases as easily as other dyes which is why it's used in many forms of dye resist art like Shibori. I used some tongue depressors to create stripes in a couple of handkerchiefs and May used wooden blocks and twine to create patterns on her shirts.

I dyed until the sun was down and the wine was gone and even continued to build up color through more dips the next day before finally replenishing my vat (or at least trying to) and calling it quits for a little while.

Huge thanks to Nick for taking these beautiful photos and to May for the delicious wine.


Sprinkling the indigo powder into the pot

Unworldly coppery sheen as I mix in the indigo powder

Keeping dye notes is important

My dye notes

Mixing up the vat while Cody works from the porch

First item in the pot, careful to avoid introducing oxygen

Wringing out the item in the leuco-indigo layer

Fabric immediately after being removed from the vat

Starting to oxidize

May and her resist techniques with wood blocks

May and the steaming cauldron

Tongue depressor resist handkerchiefs leaving the rinse


Pleased with the resulting stripes

Checking the progress on oxidizing linen

May preparing her shirts

May preparing her shirts

May preparing her shirts

Showing off my other dye experiment results

Stack of dye experiements

From the top onion skins, avocado pits, carrot tops/queen annes lace, madder, goldenrod, orange cosmos

May's resist dye technique

Sashiko Thread, shoes, linen, and cotton handkerchiefs

Checking the progress


Celebratory wine

Celebratory wine

May's resist-dyed shirt oxidizing