Friday, 1 November 2013

Making Japanese Indigo Dye from the Plant to the Wool

One lonely Japanese Indigo survived going out to the greenhouse last April.  Her name is Madama Butterfly, but there is nothing fragile about her.  The only seedling to tough out the freezing spring, she has burgeoned, shifting her pot size from tiny to biggest bucket.  
Here she is, lurking demurely at the end of August, having sucked up regular feeds along with the tomato plants.  Being my one and only plant, I was bringing her on with a view to saving seeds to sow, maybe a bit later next spring. Never mind exotic oriental blossom, there was not so much as a bud on her.

Reading up on Japanese Indigo, they say the indigo dye in the leaves is ready when an injury turns navy blue. Cruelly, I pinched one of her leaves.  Next day, the creases did look blueish. A savage harvest produced a measly 100g of greenery.  

I 'crammed the leaves' into my pot as per the instructions on my favourite dye website, Wild Colour.  After 24 hours steeping in warm water, I strained out the leaves, alkalinised the fluid with soda ash and aerated with a whisk. Then deoxygenated with Spectralite, waited an hour and dipped some wool.

Absolutely no colour appeared.  Either I did something wrong, or Madama Butterfly was an impostor.  Not the true Persicaria tinctoria, Japanese geisha and impassioned soprano Diva, but an ordinary, indigo-free Polygonum - some Slack Alice from the Rugby Club Karaoke Night. I may have kicked her pot, but I gave her the benefit of the doubt.  Rita Buchanan writes in A Dyer's Garden that Japanese Indigo never flowers til late in the season.  She recommends taking cuttings and keeping them to flower on the window sill, safe from frost.  These rooted very readily, so mid September, I potted on Madama Butterfly's Chrysalids, even though she was beginning to show white flowers, instead of the pink ones on this helpful dyer's blog.
Nearing the end of October, still no frost, but it must come soon.  Madama's seeds were appearing, but were they the right kind?
Time for an acid test - well, vinegar is an acid.  The Wild Colours website also gives instructions for a totally different method of dye extraction.  How this works chemically, I have no idea.  No mordant, no heat, no alkali and no deoxygenation.  

After the first failure, better to avoid squandering any more quality wool.  The machine washed part of my Dorset fleece had a fair portion with a blue farmer's mark.  I snipped off the stained ends, and because I am really enjoying combing and finer spinning, I knocked out three fine skeins of 15g each.  Scouring in Fairy Liquid did get rid of the last hint of colour in the wool, leaving an empty stage for Madama to inhabit.

With water chilling in the fridge, I took the secateurs to Madama's autumn regrowth and got 250g leaves, shoots and flowers.  Into the blender with vinegar and water, pour through a sieve lined with silk - bit of a sludge fest, it goes through slower than I expected.  As I squeezed out the leaves, I noticed the dry skin on my hands going blue.  Fantastic!  There had to be indigo in there, even though the fluid didn't look nearly as dark green as the instruction photos showed. By the time I had soaked and squeezed and sieved the leaves out of their second vinegar and cold water bath, the first skein was clearly changing colour.  After 30 minutes, I took it out and put the third skein in.  Not long and all three were drip drying, along with the silk from the sieve.

I am enraptured by these colours, especially the pale jade green from the resqueezed leaves in the second bath.  I've noticed before that my photos are not so good at reproducing green shades.  This is like the bluer skeins, the jade I cannot match.   It absorbs my mind.  I think it sounds like this. Which is just as it should be.

Following the instructions, I left it two days before rinsing the wool.  The colours cleared of a slight muddiness, but have stayed fast.  Imagining Madama Butterfly herself as these jade shades, if one grants an analogy with the libretto/sound, the photo shows the opera in colours.

No death at the end of my Act Three, if I can help it.  

Madama Butterfly has come indoors, carried up to sit under the skylight where she germinated.  The Chrysalids have a sunny windowsill.  Heaven knows if I will get those colours again, but next time, I'll be dyeing silk. 

Un bel di, vedremo.


  1. Your colors are spectacular. You've made me want to give Japanese Indigo a go. I love that last photo with the leaves, too, perfect compliment to the yarn hues!

    1. Thanks. Wish I could dye wool the same colours as the leaves, it would make a real drama of some knitwear.

  2. Amazing - never tried the vinegar method before, but it's obviously worthwhile.

  3. Hi, I'm glad you finally got blue:)
    I don't know why you didn't get it earlier.. maybe there wasn't enough indigo in the leaves then, or either something went wrong in the extraction, though it sounds like you did everything like you should. Was the extraction dark green after you had added the soda ash? And did the fluid turn blue during the whisking? Was there blue froth when you whisked it? If yes, then maybe the spectralite wasn't working, it goes old very easily and then it doesn't work. I was also thinking that maybe the plant didn't get enough sun, there is more blue in the leaves after hot and sunny summer than after cool and rainy summer.

  4. Hi Leena
    The extraction did go dark, but I never saw any blue while whisking. The plant did get plenty of sun, but perhaps the amount of leaves was just too small or August was too soon.

  5. If the fluid turned out blue after whisking, even if there was no froth, then there was indigo in it, and then the spectralite was not working. I don't know why there is sometimes blue froth and sometimes not, it happens to me too, but it doesn't seem to matter as long as the bath turns out dark blue, or even greenish blue. I wish you better luck next summer, growing and dyeing with indigo is so much fun, even if it is tricky:)