Failed Experiment: Bermuda Buttercup or Sour Grass (Oxalis pes-caprae) as Dye

The “dyed” t-shirt is on the left. The shirt on the right is a basic white tee. I could have achieved similar results by entropy alone.

Chalk this one up to the failures column. In an attempt to use Bermuda Buttercup (aka Sour Grass) and various mordants to dye a couple of white t-shirts yellow and green, I succeeded in dyeing both snowy white shirts a pale shade of …let’s call it ecru. Let’s not call it “grimy old t-shirt white.”

There was a moment last night when one shirt took on an extremely light, delicate yellow-green cast–and that was exciting– but the color came out when I hand washed and rinsed the shirts.

Perhaps it was a half-assed project all along. I had no burning reason to dye with Oxalis–except that it’s thick on the ground right now. Also, Oxalis is rich in oxalic acid, which is supposed to (cough) serve as a built in mordant, helping the plant dye to bind more easily to both plant and animal fibers. Oxalis theoretically yields tones ranging from lightest yellow to a sort of acid green, depending on which additional mordants you might use. Used straight, it was supposed to yield a very pale yellow.

So I thought, why not play with it and see what happens?

My only information source for this project was The Handbook of Natural Plant Dyes by Sasha Duerr. This, also, was a mistake. I usually use more sources when I start a project, but I felt lazy.

I don’t know if this is a flawed book or not–I’m not judging yet. It’s on probation. It’s a pretty book, and inspirational in that it makes you want to dye everything you can lay your hands on–hell it makes you want to raise your own sheep and spin your own yarn, so you can dip it in acorn, cabbage and fennel dye, sing some folk songs, dance a dance,  compost the solids and acidify your garden soil.with the spent dye.

It sent me into fantasies of living in some groovy Sonoma-Portlandish nirvana where my house is clean and has plaster walls and wood beams in the ceiling (the wood beams are always in the fantasy) and a fire in the grate. I’d watch the goats graze in the back yard while I cheerfully sip tea and knit something marvelous out of hand spun angora dyed with Oxalis.

(As opposed to the reality of me stumbling around our money pit of house in my exceedingly unnatural and ancient polar fleece robe, desperately searching for a chair to sit on that doesn’t hold a cat, so I can watch the LAPD stalking around the unoccupied house across the street, guns drawn, trying to nab arsonist squatters, without being in the line of fire. True story! Just happened!)

ANYWAY. Point is, the book did not serve me well in the matter of Burmuda Buttercup.

This is, therefore, an anti-project post. Following these steps will get you nowhere.

A more determined dyer or a better blogger might soldier on and find the correct answers and report them to you as a public service, but I’m sorry my friends.  I’m giving up on this one and will probably try onion skin next.

Read on if you dare.

A kitty reward for those who made the jump. Kitties like sour grass.

The first step is to weigh the dry fabric and the plant matter. You are supposed to use equal measurements of each (e.g. 6 oz of t-shirt/6 oz. plants).  The second step is to steep the plants in water. This is where I made my first half-assed mistake. I threw the plants into the pot whole, instead of chopping them up, as I was supposed to.

Then, I covered the greens with water. The instructions didn’t give exact water quantities to match the fabric weight–it only said “cover”–which seems a bit problematic. “Cover with water” is not a helpful instruction, especially when the plant matter you’re working with floats.

But I added water as best as I could judge. There were two steeping options–with heat on the stove or by a long sun steep. I opted for the long steep, put a bowl in the soaking pot to sink the plants beneath the water, and put the pot on the front porch.

The day turned out to be cloudy and cool, so I don’t believe that solar energy aided my cause. Then, I ended up leaving the pot out all night long.

In the morning some of the Oxalis had turned olive, other parts were still bright green. So I decided it was not done and put it on the stove, bringing it to a bare simmer as described for the direct heat method.

In the meanwhile, I rose above my lazy half-assery and scoured my fabric–two white t-shirts and one white cotton table napkin. Scouring is supposed to yield better dye results with cotton, so I scoured well and my fabric turned snowy white.

By this time I had realized I’d forgotten to chop the plants, but decided to dye the napkin in the plain plant brew, just to see what would happen.

Nothing happened. The napkin floated around in the dye pot, taking on no color. This boded ill. Even without chopping, surely some color should appear. I looked askance at the napkin, wondering if it were truly 100% cotton, or adulterated with polyester. We always blame the victim.

At that point I decided that I’d just start over and do it right from the start. I gathered more plants, chopped, and increased my ratio of plants to water to make the solution stronger. Then I heated the water to 180 F, simmered, drained, set aside the plant matter and returned the theoretical dye to the pot. (NB: when straining plant matter, put it through a super fine strainer, like cloth, to capture any and all solids. I had some tiny flecks of plant matter adhering to my shirts, leaving dark marks behind.  Of course, these washed out with everything else, but you may not be so…er…lucky? ) At this point I decided to add alum to the mix.

Alum is a mordant, something which makes dye “hook” to fabric, increasing the color’s brightness and fastness.  Relying oxalic acid alone as a mordant didn’t seem very promising, so I decided to up my chances of success. I added alum and cream of tartar, as directed, diluting it in a cup then stirring it into the plant infusion. Then I put a t-shirt in the vat.

Nothing happened in the suggested 15 minute dye period, so I left it for a couple of hours. When I came back, I fancied it had taken on a very pale, but sort of pretty, yellowy-green hue. I hung that t-shirt in the shower, feeling more hopeful.

Experiment #2 was to add iron (ferrous sulfate) to the dye bath. In combination with the alum, it should have pushed the dye to more a of a green.

A note here that the mordant quantities in the book were figured in relation to the fabric weight. That doesn’t account for the measurement of water– the dilution factor–which seems a bit dodgy. Water quantity, as you will recall, is just enough to “cover” the herbs.  For the record, I believe I used 3 tsp of both alum and cream of tartar in the first round, for t-shirt #1, then added 3 tsp of iron for round 2. But how much water I used, I have no idea.

T-shirt #2 went in and I let it stew forever. The water took on a nice green color, but the shirt couldn’t even pick up the pale tint that shirt #1 had acquired. It was like the dye had actually become weaker. I finally gave it up and took both shirts to the bathtub for a rinsing and gentle washing.

By this time it was dark, and so it was hard to see if anything had a delicate citron tint by the light of our horrid compact fluorescent lights. I hung the shirts up to dry.

This morning I found that indeed, the Green Fairy had indeed abandoned me, leaving the 2 t-shirts and misjudged napkin looking like they’re in need of a serious washing.

Nature. Phht. Life was easier when I was a punk kid dipping everything I owned in RIT.

Leave a comment


  1. Thanks for sharing, even though it wasn’t a success. Especially since it wasn’t a success. Blogland is too full of perfect results, perfectly photographed. If it makes you feel better, I had similar results a few years back when trying to dye stuff naturally with my kids. Dingy and muddled. Those are the words I remember using.

  2. What a great post- even if you didn’t have dyeing luck. I’m looking forward to seeing more of your experiments, I know my sister has had success with onion skins, hope you do too!

  3. I think I remember hearing that the amount of water actually doesn’t matter… it’s the ratio of dye to fiber. (This is an entirely un-researched comment, so take with a grain of salt.)

  4. I would suggest you check out the book “Harvesting Color” by Rebecca Burgess. She is also a Northern California dyer, but focuses more on native plants with some invasives. Her recipes are very exact and I have gotten some good results with them.
    I am not an expert dyer, but from what I have read the amount of water does not matter, it is the amount of dye plants that matter. Also, adding a mordant directly to the pot may make the color stick to the free floating mordant, not the garment. Ideally, you mordant your fabric separately, then rinse so there is only mordant on the fabric, none free floating in your pot.

    • Ahhhh…interesting about the water (And thanks, too, to Elizabeth who said the same thing.) This book had instructions for separate mordanting, but also for adding it to the dye bath (unless I was very confused, which is possible.) But that is exactly what happened–pretty colored water that absolutely did not stick to the fabric.

      Thanks for the book rec., too! I like the idea of working with natives.

    • I looked up the chemistry of this a while back. Mordants like alum take an organic pigment, and bind it into a white mineral pigment (a “lake”). It would be possible to dry the pretty colored water until all that’s left is the powdered pigment, mix that pigment with binder, and produce a paint that way.

      None of this applies to indigo, and I’m not sure any of it applies to tannins (oak galls, acorns, tea, and the like).

  5. Haha, “I could have achieved similar results by entropy alone.” Last year I tried to tie-dye some baby onesies with dye I made from goldenrod. They ended up the colour of baby poo, and the tie-dye patterns just made it look like explosive baby poo. I later learned that I should have stripped off all the green matter from the blossoms to get a nice gold colour. I’ll have to try again. My results looked too gross to blog about though. In the end, I did some screen printing with a brown leaf print all over the onesies, so that made the colour look more like dirt than poo, which was slightly more acceptable. Oh, Rit, why are you so easy?

    • Ha! Thanks for sharing the misery. And as to Rit — when I was doing this, I was thinking about the Victorians, and how giddy they were about the chemical dye revolution. I don’t blame them at all!

  6. I love reading a blog post about failure! So refreshing. Not to mention the case of giggles I got when you compared the utopian, Northwest, goat raising, tea sipping fantasy with the police, squatters, money pit home reality. I can SO relate!

  7. Like everyone else, it’s good to see what things don’t work as well as what works! Kris, your post cracked me up! Oh my goodness, I wish you had blogged about that!

    And you’ve found the only use I’ve found for Oxalis. My little Miss Cat loves to tackle the flowers for about ten seconds. Short attention span, that one.

  8. Oh, I feel your pain. I always say, if we had our great-grandmothers around, they would teach us how to do this stuff (and exactly what to use and how much of it to use), and we would probably have more success than using the trial and error method. It’s sad that all that knowledge, passed down from generation to generation, was abandoned at the dawn of the Department Store era. Now we have to start from square one, on our own.

  9. Thank you for your post today, and the chuckles. (stay inside when the SWAT team is out there!) Learning all this DIY stuff is HARD WORK and comes with lots of failures. (at least for me) Of course the photos of those sitting around the fireplace, spinning their own beautifully dyed yarns with a book and cup of tea at their side is inspirational. Always makes me think “I can do that!” Heck, right now my house is a mess with cat litter tracked all over and everything needing cleaning. BUT I have made a great start on planting all my fruit trees, getting the yard work done, and getting the veggie garden planned out. Please keep us informed on what works with the dyes. Both you and Mr. Homegrown make things easier for us by telling us what REALLY works! By the way how is the outside dome oven working?

  10. Pre-mordanting is the way to go. From all I’ve read, plant fibers are more difficult to dye than protein fibers. Onion skins don’t need a mordant for wool, but I’m not sure about cotton. The color I got on cotton is not as strong as it is on wool, but it worked. Since I didn’t keep notes, I don’t remember if I mordanted the cotton cloth. I did fold it accordion style and wrap it with cord to “tie-dye” it. It worked. Wool took up the onion skins well too. Try carrot tops – you will need to pre-mordant. I find the carrot tops dye best when fresh – not when they’ve been sitting in the fridge for a few days. I got a nice yellow-green with the carrot tops on wool and alpaca. I was really excited about dying with fennel last summer, but my solar results were about as promising as yours, the purple basil was about the same. I tried blue rose of sharon, and got nothing useful either. Check out India Flint’s book, Eco Dyeing – she dyes beautiful fabrics with interesting methods.

  11. Just happened on this delightful site while looking for info on preserving nopales.
    I did a lot of natural dying 35 years ago. There are a lot of worthless dye books. “A Weaver’s Garden” by Rita Buchanan is the best I found.
    Planted weld that is a great dye plant and it is still coming up in my garden!! A great yellow dye plant.
    Eva is right. Wool (or silk) is much easier to dye than cotton or linen. Checked my dye notebook.
    Dec. 1979 8 green pecan hulls stored in a Qt. of water for a month dyed unmordanted wool a nice dark brown which is still unfaded.
    Sept. 1977 Very brown onion skins soaked 2 days in water to cover dyed alum mordanted wool a nice golden brown that still looks good.
    Unmordanted wool layered with old man’s beard lichens simmered NOT BOILED gives a beautiful lustrous rust color- like red hair.
    One stannous chloride crystal added to lots of different yellow dyes is great.
    Blues and greens are almost impossible without indigo. Reds from brazilwood or logwood are the best. Yellows and browns are easy.
    It’s all fun!

  12. I’ve had great luck with oxalis, as a dye and as a mordant. Like many plants it works better on silk and wool where it gives a buttery yellow alone and a brassy yellow with alum. I actually had a couple old dingy white tee shirts that were so stained as to be useless except for gardening. I dyed them in oxalis and alum and they stayed yellow through at least a dozen trips through the washer. I use primarily flowers and cook then to 180 degrees until I have a bright yellow liquor. I then heat the object to be dyed and hold it at 160+ for an hour then leave the pot to cool down overnight.
    Try it again…….

    • Thanks Kate! I will try it again. But probably not this year. The drought has stifled the oxalis around my neightborhood — which, considering oxalis, is fairly remarkable! Here’s hoping for rainier seasons ahead.

  13. I’m a fellow plant dye novice, except oxalis was the only plant that dyed cotton to my satisfaction. Pomegranate, coffee and horsetail not so much. I couldn’t help but read your post wondering what went wrong. Here’s what I did: Rather than calculating how much plant material and water I needed, I stuffed as much unchopped oxalis with blooms as I could in a gallon aluminum pot. The aluminum in the pot has a similar effect as the alum. I didn’t chop the oxalis, but that pot was really full. I didn’t measure the water, I just filled it until the oxalis was barely covered. I covered the pot and heated it on the stove, letting it heat at a simmer for about an hour. Then I let it cool and rest overnight, really letting the aluminum do it’s magic to that concentrated oxalis tea. The next day I pulled out the oxalis, squishing out the juice back into the pot. The oxalis was a sour smelling slimy mushy mess. I heated the dye up again, threw in my cotton and let it simmer for 15 minutes. Then I let it sit in the pot for an hour our so. Rinsed it out with plain water and it was bright greenish yellow, similar to the flowers. It became a lighter, warmer yellow after I threw it in the washing machine, I think the pH affected the color, but I still liked it. The dye does become less concentrated when I added other items to it, and the fabric really absorbs the liquid. So that’s my story. I’m have to resist the temptation to save all the oxalis from my backyard as I weed for dyeing. I really don’t have anything else I want to dye yellow.

    • Thanks, Ilah! I’ll try it your way next time. As I said to another commenter recently, I don’t have any oxalis to work with this year because of the drought, but I’ll look forward to trying again next year. Fingers crossed!

  14. I’m surprised you didn’t get much color results from the oxalis. Sasha Duerr was a teacher of mine last year and our class dyed with oxalis, and it’s a plant that I have continued to use. To get the best results from this plant, it’s best to use silk or wool as your fiber. I’ve also had pale yellow results on plant fibers, but natural dyeing is a fairly experimental process and results tend to vary. Your water pH could be a factor, or you might have needed a higher ratio of oxalis to fiber. The amount of water will not effect your results. Sasha’s book is a great starting point with a lot of information on simple plants to dye with, but a big part of natural dyeing is trial and error and experimentation. I would also recommend the book Wild Color if you don’t already have it. It’s another great resource for natural dyeing. Hope that helps!

Comments are closed.