It is just beginning to bloom here, which has me thinking if I can squeeze in a couple days for dye-one for mordanting the cotton, and the next day to dye.-so much fun!
I found several articles online too:
Goldenrod is one of the favorite plants of natural dyers. The plant grows up to six feet tall with leaves two to five inches long, and clusters of small, bright yellow flowers on top. Goldenrod is plentiful in most parts of the country from late August until the first hard frost. Best colors will be obtained from plants that are in full flower. Collect goldenrod by cutting just below the flower head (watch for bees). Goldenrod, water, and alum produce a golden yellow dye. Replace the alum with iron for a dark olive-green dye. found here
HOW TO DYE WITH GOLDENROD
1 ounce of Alum
1 gallon of Water
Two non-reactive pots
Goldenrod blossoms broken off at the top of the stalks (for more pure yellows just use the blossoms)
Use equal weight goldenrod to fabric.
Dissolve alum into one gallon water. Add wet fabric, simmer for an hour. Allow to cool while you pick flowers.
Crush or bruise the blossoms then add to another one gallon of water. Cover and simmer (don't boil) for 1-2 hours. Then remove from heat, strain blossoms, and allow dye bath to cool. Add fabric and simmer for an hour or until the fabric is just a shade darker than what you want. It will dry a shade lighter. Allow the fabric to cool in the dye bath, this will set the color better. Rinse fabric when it is cool enough to handle and allow to dry. from here
and here is an article from one of my favorite bloggers that I read regularly
also I have written several posts on goldenrod, so if you do a google search for kathyinozarks goldenrod you will find them easier than going thru my tags heres one