My yarns were of a natural fiber - one was 100% wool and the other was a wool and cotton blend. They were both white so I knew that they at least would be tinted in the right direction on the color spectrum.
Yarn should be clean and un-wound for easier drying. If you dye yarn in a ball, it will probably take so long to fully dry that your yarn will develop a musty smell. It is worth the time to unwind it around your arms (or you can get a friend to help you)
I basically made onion skin tea. I added a few tablespoons of vinegar to help the color set and miraculously for this dye I did not use a mordant. I strained off the onion skins before I added the yarn.
Generally speaking with natural dyes you need an additional agent known as a 'mordant' to prevent the color from fading out of your material. I took a chance because I didn't have any alum and I tested some yarn with a light wash and the color stayed. Hooray!
After the dye bath I gave the yarn a heavy rinse and hung it to dry. (No, it did not smell like onions!)
Yes, it turned a nice warm brown color. Beautiful and within the color scheme, but I was thinking YELLOW. So I turned to the agent in my kitchen that dyes everything yellow even when I don't want it to -Tumeric!!
David is modeling the turmeric-stained cotton as a turban.
Tumeric root also has amazing anti-inflammatory properties and is delicious in curries. I had powdered tumeric and I made a strong "tea" with hot water and a generous amount of tumeric powder (about a cup of tumeric into a few litres of hot water) I also did not use a mordant for this and it worked very well.
Here is one square I was crocheting with my tumeric-yellow wool. I enjoyed a glass of my homemade blackberry apple wine as I continued to admire the beautiful yellow that tumeric makes.
This was our finished blanket, made with love and intention for our friend who has made a full recovery! I don't know if I ever told her how many onions went into that blanket.
Purple onion skins also make a beautiful purpley color when used in this way. Most other natural dye plants must be used with a mordant, otherwise they will fail. Queen Anne's Lace, rhubarb, beets, marigolds, most nut tree leaves and bark, dark berries, and many other garden plants can yield beautiful colors.
*Alum can be bought at certain drug stores - call and ask if they carry it. Alum is also useful in tanning hides, and is a caustic mineral that can harm plants. If you use it be sure to dispose of it properly - ie, not in your compost or garden.