Dyeing to be Natural

For my colloquium project, my group members and I created natural dye. We soaked pieces of fabric in salt water or vinegar, then we boiled plants that we found or bought. I picked some Rhododendrons and got bark and pine cones, we also boiled onions, oranges, Rosemary, pine needles, lake weed, and berries. It was interesting, and stunk really bad! The only dyes that turned out good were the purple onions, oranges, pink Rhododendrons, and some sort of berry. I would like to see what blackberries and blueberries would do, they seem like it would make good colors.
Pictured: the pink Rhododendrons (at least that's what I think they are!)