My gaillardia are still in full bloom! They've been blooming non stop since early summer.
Ivory Halo dogwood does very well here and is so pretty all year long. I don't think I'd recommend eastern hemlock, though, due to the dreaded hemlock disease that has devastated the east coast.
Veronicas do really well, both the tall and spreading varieties. I just planted St. John's wort for the first time and it's supposed to be good in pretty much any condition.
