I've grown Hopi Dye sunflowers in the past, but never got around to using them for natural dyeing. This year, I decided to try using my Moulin Rouge sunflowers with some natural colored peace fleece wool (Thanks, Tonya!)
Using some info from my great find (50% off at a local bookstore), I simmered the sunflowers (and stems) for about 30 minutes. Then I let the dye bath cool.
Meanwhile, I put my (already wet) wool into a mordant bath with alum and cream of tartar. Seems like there is a lot of variation for how much to use, but I used 6 g cream of tartar and 18 g alum for 100 g of wool. This simmered for about an hour. I was careful to heat it slowly and not stir the wool much for fear of felting.
Now, being inexperienced and not finding info easily, I tried to remove excess water and then put the wool into my dye bath. I let it soak for 20-30 minutes and then gently rinsed it.
I wish more of the purple color stayed, but it's mostly a grey color now.
Please feel free to chime in with any insights or advice for me. I haven't dyed wool naturally since college (!!) and I've never used sunflowers before.