Years ago, plant based dye was about the only option for coloring yarn and fabric and the plant with one of the oldest histories would have to be indigo. Indigofera tinctoria, or Polygonum tinctoriumn are two plants known as indigo. Indigofera tinctoria is thought to be native to Africa and the Middle East and one of the earliest 'recipes' for coloring fabric is a Sanskrit record mentioning indigo. Polygonum tinctorium is native to eastern Asia and Japan and is the iconic color seen in traditional shibori patterns. It is probably one of the most important dyes for many ancient civilizations and cultures with a long and respected history.
Last week, I had the chance to attend a dyeing workshop taught by Malka Dubrawsky, a respected artist and fabric designer (for those of you who sew, she designs for Moda) and one of the techniques we explored was using natural indigo dye. She showed us how to properly mix the dye and the techniques for patterning and coloring the fabric. It was a fascinating experience and I thought that it would be interesting to show you, the readers, what goes into using real indigo. Like most chemical processes, it is important to understand the materials.
Indigo is not useful in its raw form and the leaves must be harvested, and allowed to ferment for some time before dye can be made. It is a time-consuming process because the leaves are tiny and it takes a huge number of them to produce any measurable amount of dye. The fermented and dried leaves are then ground to a powder, sifted and substances added to produce the dye. Malka mixed the indigo dye and allowed the 'flower' to form on the surface of the liquid. This is a foamy, scummy sludge that protects the indigo dye from the air in the room. The longer your dye bath is exposed to air, the less effective it is. When we were ready to dye, she skimmed the flower off the surface and we dipped our projects. When we were finished, she replaced the flower to keep the dye fresh.
Most dyes work by leaving the material to be dyed in the dye bath for a specific amount of time, which achieves the desired color intensity. Indigo is different. It takes oxygen to bring out the blue, so the fabric is dipped in the bath and then removed from the liquid to 'breathe' in the open air. We dipped our fabric for a minute or so and then let it rest out of the liquid for 5 to 10 minutes. It was amazing to see the yellowish green change to blue as the fabric reacted to the oxygen. We repeated the process two or three times for different gradations of the indigo blue. When removing the projects from the dye, we were especially careful with splashes and drips, because that introduced oxygen into the dye bath which could weaken it.
As we rinsed out projects, the blue intensified, because, of course, one of the elements in water is oxygen. Our blues got brighter and the traditional indigo color was gorgeous.
Working with natural indigo is messy and time consuming, but I'm glad that I've had the experience. We also used synthetic indigo as a comparison and the color was almost identical, so I'll be using the synthetic for the majority of my future projects. However, just experiencing a little of what our ancestors did to pattern and color fabric was enlightening. The whole process was so detailed, I couldn't help to wonder who first looked at a leaf and thought to themselves...”Hmmm, I think I'll make some dye.”
There are many plants that can be used to color fabric, wood and yarn. The colors are quite lovely with an earthy, natural appearance. I was glad that I had the opportunity to explore this particular process of using plant material to color my world and it gave me a higher appreciation of what peoples in earlier times experienced when they worked with the dyes available in their day.