I haven't, but just be aware that coloring with plants/flowers can be a tricky endeavor because of the higher pH of soap. Not many plants/flowers can survive the lye monster intact. There are some that can make beautiful colors, but others turn brown. Hopefully more of the folks that use plant/flower colorants will chime in soon.
I've tried dried peony and rose petals. Both turned black, as do lavender buds. I think there are only two dried flowers that don't discolor, those are calendula petals (yellow) and cornflowers (blue). It's a shame, because I have so many things in my garden that would look great in soap...if it weren't for that lye monster! Similarly, the lovely pink pomegranate tea, and other things I've tried along the way, don't work either.