Japanese Indigo – From seed to sweater

Introduction

Japan has long been known for exquisite blue and white textile design. The traditional Japanese indigo dyeing method is called Aizome and uses no synthetic indigo made from fermented dyer’s knotweed. The blue & white colors that can be achieved with Aizome are famous around the world and unmatched in their appearance.

Indigo dyeing in Japan most commonly is used with fabric, but weavers appreciate the light and dark blues in for their designs. So far, Aizome has not been used much in yarn dyeing for knitwear design.

I am an experienced knitter originally from Germany now living in Japan. For my own designs it is my goal to use traditional Aizome techniques in my knitwear – from sowing knotweed and fermenting the leafs to producing and cultivating the dye and finally dyeing yarn for knitting my designs – the whole process from seed to sweater.

Read more at my blog.

A brief history of Ai

The indigo plant (Polygonum Tinctorium) commonly called ‘Dyer’s Knotweed’, or Ai, is one f the most used and oldest dyestuffs in the world. It is said that in Japan, dyeing with indigo, or Aizome, was already well established by the end of the sixth century. The indigo plant itself was originally imported into Japan from China and cultivated for medical use.

The Japanese word ‘Aizome’ or ‘藍染め’ in Japanese is made of the 2 characters ‘藍’ for ‘indigo’ and ‘染め(る)’ which means dyeing.

Leafs from knotweed are fermented to produce the bases for indigo dye called ‘Sukumo’.

When cloth is dyed with Ai, it is immersed in the dye a number of times until the desired depth of color is achieved. The best and purest color however is achieved. when the dye is at its freshest, immediately having been produced.

There are 2 ways to dye using Ai:

1. A dye resistant paste, which is painted on the fabric to form the negative or white space that becomes the pattern.

2. A tie-dyed style called ‘Shibori’ by binding, stitching, folding, twisting, compressing, or capping the textile.

Indigo has been said to have many beneficial qualities, such as warding off snakes and mosquitoes, and so was frequently used in old times to dye work clothes.

Ai Production

The production of indigo is a rather long process. In spring knotweed is sown, raised during summer. In late summer the first batch of leafs are harvested.

Fresh leafs can be used to dye fabric and yarns. It produces a pale greenish blue. The true indigo blue is produced by fermenting the leafs for several weeks into a product called ‘Sukumo’.

From this Sukumo and other ingredients the dyer produced his vat to dye textiles or yarns.

Indigo dye is still widely used in modern Japan. It takes well to fabrics, such as silk, cotton and hemp, does not fade very much in sunlight and still looks attractive even after repeated washing.