Since last year, we have been growing Japanese indigo at the Hitotsuya Textile Farm and using it to make our own indigo dye material.
This year, too, we sowed the seeds around the spring equinox and transplanted the seedlings to the field in May.
The sequence from sowing and raising seedlings to planting and harvesting is introduced in our Japanese-language article How to grow Japanese indigo: sowing, seedlings, planting and harvesting.
By summer, the small plants had grown large enough to cover the field.
Japanese indigo growing strongly in summer
▼ Japanese indigo growing vigorously in the summer field
▼ Lush Japanese indigo just before harvest
However, I injured my knee before summer and could no longer lift heavy loads, so I had considered giving up on making precipitated indigo this year.
Even so, seeing the healthy indigo filling the field made it feel wasteful to leave it unused.
I therefore decided to work only within what was physically manageable and make precipitated indigo again this year.
Making homemade precipitated indigo, Part 1
First, the Japanese indigo is cut from the field.
In previous years, the stems and leaves were placed in water without chopping. This year, to see whether the condition would change, the harvested plants were chopped finely before being placed in the barrel.
▼ Chopping the harvested Japanese indigo into small pieces
▼ Placing the chopped Japanese indigo into a barrel
After the chopped plants were placed in the barrel, enough water was added to cover the stems and leaves, and the soaking process began.
The photograph below shows the condition on the first day.
▼ Japanese indigo on the first day after being submerged in water
Changing the soaking time and chopping method this year
Here, we use the customary indigo-making term “fermentation.”
In practice, the leaves break down in the water, and a very strong decomposing smell develops as the process advances. For that reason, the work is carried out outdoors.
Last year, the process was stopped fairly early once the smell became strong. This year, we plan to wait a little longer before moving to the next stage.
Chopping the Japanese indigo before soaking it is also a different condition from last year.
A Japanese-language conference paper from the Japan Society of Home Economics, Study of precipitated indigo formation from Japanese indigo and its dyeing conditions, also examines differences caused by soaking time and agitation conditions.
What difference will the chopping and longer soaking time make to the precipitated indigo?
We will compare the results with last year and continue to the next stage.
The next step is introduced in the Japanese-language article Making homemade indigo paste (precipitated indigo), Part 2.
For the basic process, see our Japanese-language guide How to make precipitated indigo, indigo paste and dried indigo cakes.