So, here is what I did...
I knew that I wanted to attempt a dandelion after seeing some samples done so here is my take on it. The heads of the dandelions as well as the seeds in the wind are all fly stitch. The stems were a bit of a cheat, being made of chain stitch, but the leaves are all fly stitch as well. The simple fly stitch seam underneath was the first thing I did and it will have to come out since I think it interferes with the dandelion head.
Above there is a green stem stitch stem meandering across a seam with fly stitch leaves on along the way. Each little flower or bud was made with two bullion stitches.
This last one, in the same thread, is called Double Fly Stitch, a rather wide fly stitch with a longer narrower one over it in a contrasting colour.
I had hoped to finish this block (which you might recognize as being one I received wrapped around a Christmas Cracker) entirely in Fly Stitch but time got away from me and this was as far as I got. I am undecided now on whether to go ahead with the fly stitch variations to complete the block or move on to this week's challenge, buttonhole stitch, on another block and have this end up as yet another UFO. Tuesday came too soon and it's only the first week of the challenge!