Wondering how to make natural dyes for wool? How to make natural dyes for cotton? Plant and animal fibers have slightly different requirements, but you can dye both right at home.
You might think that dyeing is a challenge better left to experienced folks, but it can be as simple or as intricate as you make it. If you want to duplicate a specific shade, my way isn’t right for you. But if you’re happy just to get color, you can harvest multiple hues from an ordinary backyard.
I prefer natural fibers, so I use cotton, linen, and wool. Keep in mind that plant-based fibers and animal-based fibers don’t take color the same way. Cotton, linen, and other plant-based fibers are made up of cellulose, which is fairly resistant to dye. Animal-based fibers, such as wool, are made up of protein and are relatively easy to dye. Both plant- and animal-based fibers need a little help to create a good connection between the fibers and dye through a process called “mordanting.”
The Importance of Mordants
Fibers don’t offer much for dye to adhere to. So, to give the dye a place to stick, you must add something that clings to both the fabric and the dye — a mordant. Plant-based fibers, such as cotton and linen, need a tannin mordant followed by a metal mordant. (The exception is black walnut, which doesn’t need the help of a mordant.) For animal-based fibers, such as wool, a metal mordant is enough. You can dye wool without any mordant at all, but the color won’t be as vibrant. If you’re dyeing wool, skip the paragraph on tannin mordants and go right to the paragraph on metal mordants.
Tannin mordants
Two good natural sources for tannin mordant are sumac and rhubarb leaves. Because rhubarb is readily available in spring, and sumac is easy to find in summer and fall, these two plants make a good three-season source of natural tannin mordant. For each pound of dry fiber, use 4 pounds of leaves. Add your fiber to a stainless steel pot, pour in enough distilled water to completely submerge the yarn, and then remove the yarn. Put the sumac or rhubarb leaves into the pot (adding more distilled water if needed for complete submersion), and boil for an hour. Then, remove the greens, return the damp fiber to the pot, and let it steep for an hour or two before removing it. Next, you’ll need to make a metal mordant.
Metal mordants
A good metal mordant is aluminum sulfate, commonly called “alum,” which is fairly inexpensive and can be found in the spice section of most grocery stores. Measure out an amount of alum that’s equal to 10 percent of the weight of the dry wool, or up to 20 percent of the dry weight of any fine silk, cotton, or linen. (For wool, keep in mind that too much alum can damage the fibers and make them feel rough to the touch.) Add enough distilled water to a pot to completely submerge your fiber. Take the fiber out and set it aside. Then, add the proper amount of alum to the water, bring to a boil, turn off the heat, add the damp yarn to the pot, and let the yarn steep for about an hour. This will give the yarn and mordant solution time to cool down enough so you can wring out the fiber for the next step: the dye bath.
Making the Dye Bath
To make a dye bath, add your plant of choice to a stainless steel pot and pour in distilled water to cover. Cutting your plant material into small pieces will help the color extraction process. Boil the bath for about an hour. During this time, the plant material should impart its color to the water. Turn off the burner and let the dye bath cool. Strain out the plant material and add the mordanted yarn to the dye bath. If you used a colander to strain the bath, you can place the plant-filled colander on top of the fiber to help submerge it. Let the dye bath sit overnight. The next day, with gloved hands, rinse the dyed yarn in cold water. Let the yarn dry completely out of the sun before washing it with soap.
Most fibers benefit from prolonged exposure in a dye bath. In the case of goldenrod, the flowers are a potent dye and will impart a bright yellow color — 15 minutes is usually the optimal time. The longer you steep fabric or yarn in a goldenrod dye bath, the deeper the color will become. At some point, though, the goldenrod’s stems and small leaves (which dye brown) will darken the yellow color. When dyeing with yellow onion skins, you can steep the fabric overnight to darken the orange to more of a brown. Black walnut is a powerful dye, making it good for beginners.
I’ve dyed plant fibers and animal fibers and have gotten wildly varying outcomes. Natural dyeing can yield spontaneous results! For instance, a linen dress I was hoping to dye a deep brown with black walnut turned into a beautiful yellow-copper instead. Dyeing is such a beautiful way to see nature and chemistry in action — the difference the nature of fibers makes; the difference a bit of metal mordant makes; the way some dyes strike enthusiastically but others need overnight soaking. Natural dyeing is certainly a wondrous adventure.
Susan Verberg
Ithaca, New York
Have a DIY step-by-step project? If so, we want to hear about it. Send us your plans (with pics) and you could earn up to $150 if we publish your project in the magazine.