This is the question I get the most often: How can I make botanical colors last using natural methods?First of all, we have to define natural. Then, let’s define mordants. I will talk about metal salts, like alum, iron, etc., as well as binders, e.g. soy milk. I am also listing alternative processes, like indigo dyeing, tannins treatment and acid dyeing.To illustrate how different mordants influence color, I dyed a few swatches pre-treated with different natural substances. I used onion…
