Friday 31 May 2019

Madder Root Dye with Alum, Rhubarb and Iron as Mordants on Wool

"Perhaps I could mordant six small skeins of yarn, two of each with alum, iron and rhubarb, dissolve the calcium carbonate a day in advance, get hold of some real bran instead of using porridge oats, give the madder roots a boiling water rinse before chopping them up, then divide them into two dye baths and process one by heating to 80 degrees Centigrade and keep the other at room temperature for a week. Then I could compare the results and find out which works best, hot or cold madder dyeing. Only the cold bath would ferment over time and get more acidic than the hot one and that would affect the dye colours. I could keep adjusting it every day - what pH do you think I should aim for?"
I looked at my companion, Elinor Gotland, who got up from her chair.
"Madder, madder, bloody madder. It's all you think about."
"Exactly. I mean, I'd love bloody madder." I called after her retreating back. "You might be a bit more supportive. You'll see, when I've decided how best to optimise all the variables, I will get blood red out of these madder roots."
Elinor turned and blew me a theatrical kiss.
"Why not keep it simple, sweetie?"


Three 50g skeins of wool yarn were mordanted, one with 10% alum, one with 2% iron and the third was simmered with three rhubarb leaves to soak up some oxalic acid.
An equal weight of 150g dried madder root was chopped up in the kitchen blender, boiling water was poured over it and the pot was left to steep overnight. 


Next day, I added the three skeins, heated the pot until it was properly hot but not boiling, kept it hot for an hour and allowed it to cool overnight. No rinsing the roots beforehand and no additives at all, not even soda ash to raise the pH of the dye, which proved to be naturally mildly acidic when tested with indicator paper. 



Here are the results, fresh from the dye pot. The alum mordanted yarn, which was Blue Faced Leicester wool, had turned the truest red I have achieved with madder in ages. The rhubarb mordanted yarn was far more orange and the iron mordanted yarn was milk chocolate brown. I've read that alkaline modification can turn that brown to aubergine, so the iron mordanted skein had a soak in warm water with a teaspoon of soda ash before being hung up to dry.

"The brown one hasn't really gone quite purple enough to be called aubergine, but I'm astonished and so pleased with these colours. Particularly the red. Wish I'd used ordinary old alum mordant on all three skeins. I'd never have believed that you could get a good red from just madder roots and water."
I turned to my companion and to do her credit, detected no trace of smugness in her expression. She shrugged.
"Less is more, Beaut."
I put 100g of my finest alum mordanted Falklands Merino and Tussah silk blend 4ply yarn into the madder root bath and heated it up again next day. Even the afterbath gave a truer red than I have become accustomed to. Maybe I'll find I can't replicate the conditions and do as well every time, but it's tremendously heartening to get a win when you least expect it.



19 comments:

  1. Great colours. Do you leave the chopped madder in the pot throughout the whole process?

    ReplyDelete
    Replies
    1. Thanks. I do leave the madder root in the pot, I've found my blender chops dried madder to a gritty powder. Takes a few rinses to get it out and it's a total pain with fleece or tops, but not bad with yarn.

      Delete
  2. Those are amazing colours! Well done! Now, do you have more of that particularl batch of madder, too?

    ReplyDelete
    Replies
    1. Not a lot - it was nearly the last of the barrel full I dug up last year. I am trying to repeat my success with the last 100g :)

      Delete
  3. Wauw ! Less is more, indeed. Wonderful !

    ReplyDelete
  4. Great reds...so hard to achieve!

    ReplyDelete
  5. All your experimentation is marvelous! Thanks for being so thorough, and then writing about it so cleverly. Gorgeous colors you got!

    ReplyDelete
  6. VegetablesMatter7 June 2019 at 05:19

    (Btw, whenever I post, I try to put my moniker--VegetablesMatter--but it never seems to come through.)

    ReplyDelete
    Replies
    1. It worked - VegetablesMatter - do you spin yarn by any chance and is that a pun on VM?

      Delete
  7. when I see that red my fingers get itchy:) after first Dh "helped" and threw my madder plants in pots away, DS did the same this spring and "weeded" that stuff:( I am left with only 2 plants, so I'll have to wait and grow more before I can dig my own roots again. but - I still have some madder in storage... there was a discussion on FB that older madder looses some of its strength, so I'll better use it up soon!in the hope that I'll get reds too and not orange:)

    ReplyDelete
    Replies
    1. I saw that thread, but there's not much chance I'll keep my small harvests for much over a year :)

      Delete
  8. Hi Fran, I also love that madder red. There is a great article in the Journal of weavers spinners and dyers this time about Norwich or cardinal red. There is a modern interpretation of an old recipe that uses 0.6g of cochineal with an alum and cream of tartar mordant followed by boiling in madder dye for 4 hours! I tried this but could only bring myself to heat the yarn for 2 hours and the red was really lovely. I am going to repeat with 4 samples taking one out each hour to find that sweet spot.
    There is so much to learn about Madder but what was unusual about this recipe was the temperature. Much higher than normally recommended!

    ReplyDelete
    Replies
    1. That's fascinating - everything I've read cautions me never to boil madder - but once I've harvested another tub I might get up the nerve to try it :) Thanks very much.

      Delete
  9. inspirational,am really going to have to try it,as soon as I can source some madder plants.




    ReplyDelete
    Replies
    1. Had you thought of starting some madder seeds? I expect they would germinate easily in summer.

      Delete
  10. Fran, I love your blog. I am in Oz and started spinning a year ago, and now am venturing into dyeing. I have loads of ivy, hawthorn and some dried madder root that I am about to try. I have Jenny Dean's book, but I find your blog more informative as to what to expect re colour. Thanks

    ReplyDelete