A friend gave me dried flower heads labeld Rittersporn Buuten (thanks Lindy) - about 6 ounces. These are Larkspur and I found a site that lists the colors you can expect from different plants : http://www.pioneerthinking.com/naturaldyes.html. It indicates I should get a green if using the Alum mordant.
I mordanted 8 oz of fleece with Alum and simmered the Larkspur for 2 hours in water then cooled overnight.
I thought 6 oz dry weight would have coe from about 12- 18 oz of fresh flowers but I didn't know how much fiber it would dye. I gave a very dark liquid which when tested on white kitchen paper showed a faint light green.
I decided to add 4 oz of the fiber, simmered for an hour after which it seemed virtually unchanged :(. I left ot overnight and next day the fleece seemed barely dyed with a very light green hue.
After it dried it appeared a more definite green. When spun it looks like this:
A Sage green. At first I was disappointed as I thought I would get a dark green, then I was annoyed that I had put so much fiber in (perhaps 2 oz would have been better) but now it's growing on me, so to speak - and I've come to really like it's subtle gentle green.