The market for organic indigo dye is making a come-back in Oaxaca as more textile artists and weavers are choosing to work with the natural plant material. Today, the state of Oaxaca produces about 100 kilograms of añil or indigo each year. Up until about three years ago, the indigo dye making process had almost died out in Oaxaca.
To stimulate the economic development of indigo as a crop, the state government has made investments to help the producers develop new markets. The Museo Textil de Oaxaca gift shop sells small bags of indigo along with “how to” DVD’s and recipes. I learned this and a lot more during the indigo dye workshop I participated in at the Museo Textil de Oaxaca, where about 15 people gathered to learn shibori and tritik dye techniques using indigo.
The people in Santiago Niltepec, on the coast of Oaxaca near Juchitan on the Isthmus of Tehuantepec, pick the wild plant, chop it — stems and leaves — and put it in a fermentation bath for at least twelve hours (sometimes as much as thirty-six hours) to prepare the dye. Each family has its own recipe for making the indigo paste. Most use rocks to keep the plants submerged below the water to make sure that they oxidize completely and yield the deepest color.
The process is ancient, thousands of years old. The plant material decomposes and collects at the bottom of the large vats as a thick paste. It’s then strained to separate any sediment. The result is a highly saturated, concentrated product. It takes about 200 kg of plants to produce 1 kg of indigo dye. It is then dried and becomes rock-hard. To then use it, it must be pulverized into a fine powder. Traditionalists in Oaxaca use a metate or mortar and pestle. Others take the faster route by using an electric coffee grinder.
Indigo can’t be dissolved in pure water. It has to be dissolved in a highly alkaline solution with a 10-11 pH, and free of oxygen. Eric Chavez Santiago, director of education at the Museo Textil de Oaxaca, told us that there are several ways to manipulate the chemistry by using either sodium hydrosulfide (highly caustic) or the more organic fructose crystalline. French botanist and dyer Michel Garcia is now experimenting with using mango skins and fructose successfully.
Eric says it is important to be patient when dyeing with indigo. You can use the dye within thirty minutes after preparing it, but it often takes three or four days of fermentation to get the deepest shades of blue.
During the workshop, we dipped our white cotton material at least twice for 20 minutes each time, to intensify the color. Some people even dye their hair with indigo!
Tapestry Weaving and Natural Dye Workshop this summer 2012! Don’t miss it.