Karen: How about some of the hybrid echinaceas? I've had several that haven't reseeded at all. Some suggestions: Coconut Lime, double pink, Milkshake or Meringue (sp?) These have all done really well in my garden for a few years without throwing seeds/seedlings. I've also had bottle gentian for a few years without reseeding, as well as aconitum (monkshood). Turtlehead (chelone) don't seem to spread agressively, either.
