As natural dyes are also more eco-friendly, my husband and I decided to test the effectiveness of different plant sources when dyeing cotton yarn. We found that some of the plants were much more effective than others, and that certain techniques helped the plants to produce better results.
When undertaking any dyeing project, it is important to use a mordant (or fixative) to help the dye to set. In this case, I used alum (dissolve in water, and soak the fibers to be dyed in it for at least 15 minutes but I have read that it can be soaked for up to an hour an a half) before the dyeing, along with a follow-up soak in a vinegar bath at the end of the dyeing process.
Some natural dyes will give different results when copper or iron is added. In this case, we used some reclaimed copper wire placed in the bottom of the dye pot for some of my experiments.
Here are the results:
Annatto - Annatto, the seeds of "the lipstick tree" are also known as the food coloring E160b. Annatto is native to South America, but when it was brought back to Europe by the conquistadors, it quickly became important in dyeing not only foods, but Spanish silks as well. When used to dye cotton, it produced a rich, light salmon color.
Turmeric - Turmeric is a rhizome plant native to the tropical areas in India also know as the food coloring E100. It is not used extensively in dyeing cloth, due to its color fading in sunlight, but the Spanish did use it for dyeing silk. We grated the roots and boiled it in water to release the color. Even then, the color was a light golden yellow. This color was dramatically enhanced by adding copper to the dye pot.
Safflower - Safflower is one of those herbs that have been used primarily for dyeing since before the innovation of scientific names. Therefore, when it was named, it was labeled with the term tinctorius (which basically means "used for dyeing"). This designates the traditional dye plants, which also include madder and indigo. The result of using this dye was rather disappointing, as it imparted only a simple yellow hue.
Henna - Henna is a small tree native to northern Africa and southern Asia. It has been popular as a cloth dye in a number of different parts of the world (It caught on in Europe in the 1800s for this purpose). The dye is derived by grinding the dried leaves and mixing with an acidic liquid such as tea or lemon juice (We bought ours in a powdered form). The directions said to let the mixture sit for a few hours and up to a day before it is ready to use for dyeing. We used a few table spoons for the dye bath. It produced a lovely light brown color.
Onion - This probably isn't the first thing you think about when you think of dyes, but it produced one of the deepest hues. We mixed red and yellow onion skins, on the principle of the more color the better. Only the dry papery skins should be used for dyeing. It left no odor since only the outer skins were used and produced a dark dye bath. The result was a Dark golden brown with a hint of green to it.
Mesquite -- Mesquite is a thorny tree found in many parts of Texas and other states. We read that it could be used to make a sort of blue. We harvested some of the bean pods as well as leaves, the parts it said to use and simmered them for a while trying to extract the dye. It merely made a yellow green tint to the water and no blue. We tried to dye with it anyway just in case it changed color after it dried but to no avail.
Red Beet - Red beets have been cultivated in a wide range of areas for a long time in Europe, Asia, and Africa. The term beet red is used to describe a deep red color. It would seem natural that beets would bake a nice dye for cloth. We tried it on cotton and our hands seemed to take the dye better than the cotton which, while a beautiful raspberry color when it first came out of the dye pot, faded over the next few days and ended up a dingy off white color. We also tried to dye wool with it which took it much better but still was a pink color rather than the expected red.
We are planning on continuing our dyeing experiments, as the process produces beautiful results and great satisfaction. I hope you too give it a try.