Process and Dyeing Methods
"It takes about a year to produce indigo dye - and that is before the actual dyeing has even started."
It takes about a year to produce indigo dye - and that is before the actual dyeing has even started. Needless to say, aizome is a very time-consuming process fit only for the most devoted of artisans.
The seeds are sown in the spring and harvested at the end of the rainy season in summer. Then starts a process to produce what the Japanese call sukumo, the end result of an elaborate fermentation and drying process. Come spring again and we're ready to start dyeing.
But first, time for some sake. Not for us to drink of course, but for sukumo along with water, ash lye and lime. After a couple of days of carefully tending to the brew, bubbles known as ai no hana (more on those here) start to form. That indicates that the dye is ready to be used.
The color produced by dipping textiles in the dye is actually green - it's when you hang them out to dry that it turns blue from the exposure to air. The longer you let the textiles soak and the more times you repeat the dipping and drying process the stronger hue of blue you get. The different hues each have their own names, where the lightest is called aijiro and is the color enrobing the Tokyo Sky Tree.
There are two main ways of creating patterns with indigo dyeing: tie-dyeing (shibori) and the paste-resist method (katazome). The former involves tying a string around the fabric to be dyed in order to create elaborate and unique patterns, as the tied parts resist the dye and create a kind of blurring effect. A breathtaking form of tie-dying called Yamamichi shibori resembles paths snaking through a mountain.
In the paste-resist method a stencil is created that is placed on top of white fabric before it is dipped into the dye. When the stencil is removed the undyed white parts form the pattern.
Indigo dye doesn't fade and remains vivid for hundreds of years. Rather, it matures with age and takes on a luster impossible for synthetic indigo to mimic.