We collected some sunflower blooms from some clusters by the side of the road. Leece is experimenting with yarn dyes from these blooms. So far she has really liked the bright golden-orange, on wool, from marigold blossoms. Echinacea blooms from the garden, with an iron modifier, gave a rather nice battleship grey. We got the iron modifier by soaking old iron nails - no coatings on them - in a slightly acidic solution for several weeks. We used white vinegar for the acid.
Here are some articles Leece has written about dyeing with natural products:
Dyeing Yarn Naturally (this is the marigold article)
Madder Yields Shades of Red (Madder root was used extensively for reds, for centuries. Did you know that the red stripes in our early flags were dyed with madder root dyes? Also the red coats of British soldiers?)