Well, I have a few plants for my spot so far. I had a leftover blue Campanula pyramidalis so I'm going to put that at the back. Thanks for that suggestion, I would not have thought of using it there. And, I also had a leftover monarda, so I'm going to put it next to the campanula (what the heck, it might get enough sun there).
I think toad lilies will do well there, so I have some ordered that should arrive today, along with a couple of small anemones. For ferns, I ordered some lady ferns and a Japanese painted fern. Also included a hellebore I've been drooling over.
Couldn't find any bleeding heart this time of year, but I'm going to try the seeds over the winter and if they don't work out, I should be able to find plants come spring. AND, in researching ferns, I discovered that my very favorite fern, Maidenhair fern (Adiantum capillis-veneris) is hardy to zone 5b, so I just might be able to include one of those in this spot.
I appreciate the suggestions, and I AM going to try those Meconopsis seeds again. Does anyone know if it's possible to order Meconopsis plants anywhere?