Friday, 8 August 2014

Japanese Indigo Plant Dyeing with Extraction Vat and Spectralite

A hot July by local standards has suited the Japanese Indigo plants growing in the garden. So many seedlings came up in trays this spring, spares went out in the earth in April, rather than hit the compost heap.  Too cold, those were terminally stunted or just disappeared.  I have already had one harvest from the six that stayed in the greenhouse and the potted ones that were planted out in May are now going great guns.  Even the plant in a shady border developed blue marks after I crushed a leaf. Taking the secateurs round the half dozen outdoor survivors provided another 450g of leaves and stems to dye with.  Time to try again at getting the indigo out with an extraction vat.

The instructions on the Wild Colours website are not complicated.  After failing with this process last year, I was scrupulous in following them to the letter.  The leaves in the bowl were steeped in hot tap water, with hot water in the sink renewed three times over 24 hours, the whole thing being covered to retain warmth.  Blue showed at the edge of the washing up bowl and the leaves had leaked out a promising deep brown bath. 

Several sources say that Japanese Indigo has twice as much pigment in it per weight of leaves compared to woad.  The vat doesn't smell the same, pleasantly vernal rather than boiled cabbage.  After extraction, the process is much the same for the two plants.  I carried on with the soda ash and the aeration then the Spectralite, hurriedly putting a bit more fleece in for a soak, now expecting plenty of blue out of this vat. What with the Tour de Fleece spinning, I had no Polwarth yarn prepared, but I did have about 50g scoured fleece which got the first and second dip.  This did take up a much deeper blue than I've had from vinegar extraction.  Now I've spun it up, you can compare this wool to the two vinegar method skeins.
I do winge about this, ought to go and talk to someone who knows about photography, but my camera is not great at picking up shades of green.  While pale, the vinegar method skeins have a subtle green cast to their blue which is hard to describe.  The deeper blue is pretty much as shown here.  A simpler colour, very close to what I have had from woad.  At the end of the session, I put in a last bit of fleece to take up whatever dye was left.  The remnant of the bath, shown below, gave a more turquoise shade.
Considering the three balls, I am not that impressed with them as a colour sequence. They don't go together in the way I had hoped. 
A further disappointment of this vat was how little colour was taken up by my silk jersey fabric and cotton scrim.  They looked quite exotic while damp, but I wouldn't bother putting up a picture of the result when they had dried.  Drab is the word that comes to mind.

I would have expected 450g woad leaves to give a good mid blue to at least 150g of materials. Japanese Indigo is supposed to be stronger and I had believed the extraction vat would dye silk and cotton better than the vinegar method did.  Most likely, I did things wrong at some point, but I can't for the life of me work out what.  So far, vinegar extraction and dyeing on wool has proved quicker, easier, cheaper and considerably more rewarding in terms of colour interest, if not depth.

"Someone's lost a shilling and found a sixpence."  Elinor Gotland, astute as ever and twice as annoying.
"Oh, I was hoping to make something using a sequence of Japanese Indigo dye colours to represent Act Two of the opera, Madame Butterfly.  When she's waiting for Pinkerton's return."
"What, all naive pining and ill founded expectations?"
"I mean constancy despite isolation, depth of spirit in adversity, enduring faith in love. Should have thought you would relish that operatic passion."
"Not my bag, Beaut.  Gazing out to sea from the cliff top never buttered any girl's parsnips."
"What would you have done, if you were Cio-Cio-san?  Smiled at another sailor?"
"Think I'd have spotted that everyone in my life so far was just out for what they could get.  Cio-Cio could have made a success of the geisha business, retired on the proceeds and done something interesting, like study haiku."

"Butterfly escapes 
Japanese Indigo leaves

"Indeed.  Now get a grip and stop contemplating ritual seppuku over a bit of blue wool.  Time to steep some cheerful leaves. A nice tea ceremony will soon put you right."


  1. Thanks to the writer of this article. I appreciate your effort in making this informational blogs. I know it's not easy to do this but you have done a really great job. I'm pretty sure your readers enjoying it a lots.

    1. Much appreciated. Rereading this post, I can feel the emotional temperature of that period of my life. Not tops. Took a while to decide to make things change, now they have, I am considerably more sanguine about a disappointing dye vat :)