...with red cabbage of course! Here are my results from two rounds of dyeing with red cabbage. These are silk and wool, scoured first, and then mordanted with alum. Straight red cabbage water gives a beautiful purple. Adding baking soda gives a blue or green depending on how much baking soda you add. Adding vinegar or lemon juice gives a magenta. The wool had a yellow tint to it, so that warmed up the colors quite a lot.