It's too bad you lost so many hostas - they really look nice in the photo.

Planting perennials/shrubs above ground level in a raised bed can be a tough call given that your bed is only 18" wide. The root structure may be freezing too solid without any type of insulation (soil) on either side.

I don't think, though, that it's a lost cause. I'd certainly attempt Bergenia and Lady's Mantle in there. Bergenia would have the benefit of being semi-evergreen, has early growth and nice fall colouring. It blooms early (mine is blooming now). Lady's Mantle frothy yellow blooms last a long, long time and would spill (a much nicer word for flop) over the logs. I have Lady's Mantle planted right next to where I tie up one dog on occasion. She is merciless with that planting and it survives without a hiccup. Lamium could be another option, as well as Solomon's Seal.

Did the ferns survive? If they did, they may eventually take over the whole bed - if they like a spot they can be quite vigorous. On the other hand, I have tried to grow ferns unsuccessfully 3 times and I'm throwing in the towel - I'll just salivate with envy at everyone else's ferns that seem to grow with wild abandon.

Thanks for the ideas. I have had no luck with Lady's Mantle in the past but I may try it there.

The ferns are growing between the planter and the fence all on their own. I didn't put them there... I guess I am one of the lucky ones as I have them growing all over the yard. In that particular spot, they grow to over 5 feet. They are Ostrich ferns.

I had lamium there last year and only one clump survived. I am hesitant about the Bergenia as I have a few clumps in the yard but have absolutely no luck with them growing to any size. They are puny and remain so after even 5 years. Maybe I need to look at a better cultivar.