Grackle & Sun

At the Burrow DyeTable # Five: Red Onion Revisited

After seeing the awesome green that my class got from the red onion skin dyebath the other day, I didn’t have the heart to chuck out the exhaust.  I knew that most likely my results from the same bath, which had been sitting on the back porch for 3 days, would be quite different, but I had yarn already mordanted practically screaming at me to go play.  So, play I did.  Husband kept me company, which made the whole thing infinitely more enjoyable, and I really like dyeing, so this was pretty damn good.

And, in the middle of it all, we heard a loud noise, looked up in the sky, and saw this behemoth flying low, low, low overhead.  Unexpected, right?  It had propellers.

Alright.  Back to work.

Dye Notes:

Dyestuff:  Red onions

Parts used:  The papery outer skins

Source:  The restaurant where I work, my kitchen, and grocery store onion bins

Ratio of dyestuff to yarn:  The original dyebath was roughly a .75:1 ratio of skins to yarn.  If I were to go strictly by weight for this exhaust bath, it would be about 200g onion skins to roughly 36g yarn, which is a just about a 5.6:1 ratio.  However, since this is an exhaust bath, and I have no idea how one would even begin to calculate how much dye has already been removed from the skins, the weight of said skins is very nearly meaningless.  I wish there was some way to figure it out, but it is beyond my arithmetical skillz, of which there are few.

Yarn:  Lion Brand Fisherman’s Wool mordanted with 8% aluminum potassium sulfate and 7% cream of tartar.

Dyebath:  Added just a little glug of white distilled vinegar before heating, thinking that lowering the pH might help me get the pinks that red onion are supposed to give in a more acidic bath.  The pH at room temp. was 3.6.  Once the bath came up to temperature (195F), I remeasured the pH to be 3.4.  Initially, when the yarn was added (at room temp.), it seemed to take in the claret colour.  But as soon as the bath started heating up, it became clear that it was going to turn toward yellow.  Eeeeeenteresting….  Held the dyebath between 175F-195F for 1 hour and then let the yarn cool in the pot for several hours.

The results?  A weird burnished golden green.  Here it is straight from the dyebath:

And here is the skein after being rinsed and dried.  That is NOT pink.

It’s hard to describe just what this colour is.  The picture doesn’t capture just how much of a strange, otherworldly green cast it has.  The best way to describe it would be to call it… tarnished.  I rather like it.  But it is not what I was expecting.


Then later the same day another little hank of premordanted yarn called to me, and I decided to bump up the pH dyebath and try it one more time.  It still seemed to have so much colour in it.  So I added enough washing soda to get the pH up to 9.4 at temperature.  The colour of the bath immediately went from red to green.

In the original dyebath, after we got the pH over 9, we saw the same colour shift of the bath, but then it turned acidic (and red) again pretty quickly.  I assumed this was because I’d left the bag of onion skins in the bath and that they were still influencing the pH.  So this time, I took the bag out before bumping up the pH. I did, however, add a few fresh red onion skins I’d snagged from the restaurant this week.  No more than a couple grams.

But it didn’t make any difference.  Even though the bath stayed green for the hour that I heated it (in the same 175-195F window). after it was left to cool overnight, the next morning it was claret red again.

The results?  Not green.  Or pink.

So what was going on here?  I must begin with the disclaimer that I have no idea.  But if I were to guess, it would be that there are a couple different components to whatever compounds are in red onion skins that make them red, and that the uptake of those components occur at different times.  It is my understanding that if you take red onion skins and make a fresh dyebath with them, and leave the bath acidic, you can get pinks on your fiber.  If you take that same fresh dyebath and make it basic instead, you will get greens on your yarn—even though the bath looks red.   And that is exactly what happened with the original bath.   The kids got green yarn.  Very green.  Clearly, in the first exhaust bath, the green dye was all but gone.  In the second bath there was none left—even though the bath was alkaline.   So, I would venture to say that making the bath alkaline is what extracts the component that dyes green, and that it is taken up before the other components that dye either pink or yellow.  I would like to try red onion again and get pink from it, because I think this would help clarify what is happening chemically in this bath.  I’m really just guessing about all of it at this point.

Any of you have experience dyeing with red onion skins?  What do you think?

Live happy, dye happy!

Single Post Navigation

23 thoughts on “At the Burrow DyeTable # Five: Red Onion Revisited

  1. So interesting! Thanks!

    I do not have much experience with red onion skins, as to some reason I prefer common onions.

    But according to my reference book, which is a study of 160 local Ukrainian dyeing plants accomplished by my fellow-chemists technologists from Lviv Academy, the results you’ve got are the common output on the alum mordanted wool yarn.

    The green your class got was really a surprise. What mordant was used then?
    And also, may I ask if it is still that bright green if you could check, please?

    Of course, we may have a slightly different variety of red onions in the first place!

    Anyway, thank you for an interesting post.


    • Thank you! The wool used for the children’s class was the same that I used for this experiment: Lion Brand Fisherman’s Wool mordanted with 8% aluminum potassium sulfate and 7% cream of tartar. I’ll have to ask if the green is still as vivid, but I’m going to assume that the answer is yes just due to onion’s natural lightfastness. Everything I’ve read says that green is achieved by changing the initial pH of the dyebath to alkaline. I’ve seen some amazing greens on Ravelry’s natural dyeing forums with this method.

  2. I’ve never dyed anything with red onions but my instincts would’ve told me it would be pink…not green or even the beige/tan colors you got. That’s kinda cool :)

  3. hiya :) we are after pokeweed.. any chance we can nick yours? or just a cutting? (if your in england)

    • Interesting. I don’t know if pokeweed grows from cuttings or not. I’m inclined to think it wouldn’t. It’s a perennial that develops a very deep taproot, but otherwise grows from seed. Sorry, not in England. Don’t know if any pokeweed grows there.

  4. Ok, thanks anyway. Yh it can grow everywhere but antartica apparently

  5. I really love those colors. I think I have knit with both of them in the last two months!

  6. I’ve dyed a lot with onion skins, but never tried to change the PH. When dyeing with onion skins I never mordant. One of the things I really like about them is that they don’t need mordating. To achieve green I dip the dyed, unwashed (but moist) yarn/fabric in rust water.
    Mostly I achieve a colour like yours in the second photo from onion skins alone – and a deep green after the iron treatment.
    But I might try changing the PH next time – just for the fun of it! :)

    • Do you do the iron after-bath with red onion skins to get green or with yellow onion skins? I have some iron liquor, I might have to try that. :D I’ve not done a lot with iron, because I’ve heard that it can damage fibers. Have you had a problem with that before?

      • With both – you get different shades of greens …
        I use old rusty nails and other old iron things I find, keep them in an pot with rainwater. Strain it before use.
        It doesn’t get as strong as the iron powder you buy. According to India Flint the iron doesn’t damage the wool, and I haven’t noticed any damage to my yarn with this kind of treatment. If you use cold water for the soaking and no longer than 15 minutes in the iron water you should be on the safe side.
        I believe that strong alkaline treatments are more damaging to the fibres than iron … but that’s just my opinion …

      • Thanks for the information! I definitely want to try this.

  7. I am yet to try red onion skins, and have never seen pink from them. I love your Ph experiments!

  8. Wow! Interesting where a Google search of the phrase ‘pokeberry plants Missouri will take a person. The Friendship Spinning guild in Kentucky, of which I am still and honorary member, had a natural dye-in every fall, but pokeberry was never used. Apple bark, indigo, goldenrod, etc. yes. I had tons of berries available to me, and a friend gave me Rita Buchanan’s recipe and I had great results of dark burgundy. If you care for the recipe, I will happily email it to you. Nancy

  9. Pingback: Knit|tinK: A Witch’s House Socks « Grackle & Sun

  10. Ingrid on said:

    FOR OLIVE GREEN : use 15 percent red onionskins to wool ( 15 gram skins for 100 gram wool) . No alum/acid/iron needed, so wool stays as soft as it was.

  11. Hi,

    I love your blog. Just ‘my’ subjects.

    I tride onin skins quite a lot and they always perform well and resist light. Red skins make green wool and yellow skins brownish wool with my water and setup. I’ll keep hanging arround to see how your other projects proceed. If you fancy a look at my blog, I’m sorry to say I only write in Swedish, but I’l be happy to translate if you’d like to know more about something.


Add to the conversation :)

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: