Before the invention of the synthetic dyes, people had to use natural dyes. As I’ve indicated in previous posts, that was not always positive. A poor growing season could mean a weak dye (besides the loss of the crop which was always an issue). There was no way to control the dye and achieve the exact same result every time.
Dyes like cochineal were expensive. And Madder, a dye plant a dyer could grow in the garden, can take 4 – 5 years to reach useability.
Another problem was colorfastness. Turmeric, for example, is a wonderful yellow dye. But, without mordanting, it fades to a muted yellow. In the post colonial period, when iron and copper pots were in use, the dyes were mordanted almost without consciousness. (Of course, food was cooked in copper and iron pots too. Yummy!)
Here is a way to use onionskins.
First, make an iron mordant by soaking rusty iron nails (stainless steel won’t work) in white vinegar. In 1 to 2 weeks, the vinegar will turn a rusty orange. Put in a stainless steel pot with enough water to cover and add fiber or fabric (cotton). Simmer gently for ten minutes and wash thoroughly to remove iron particles. Now you are ready to dye.
Wet the fiber and soak for at least an hour. Place onionskins (4 oz) either brown or red, in a pot and bring to a boil. Simmer for about 15 minutes until the skins are clear. Scoop out the onionskins and add fiber. Soak until desired color is reached. Red skins will give a bright yellow or yellowish green, and brown will give a rusty orange/gold.
Rinse thoroughly and hang to dry. Although mostly colorfast, you will notice it fades more rapidly than the synthetic dyes. However, it is not toxic at all.
More natural mordants and dyes to come.