Need a perennial shade flower for zone 5?

I have areas in my garden (zone 5) that are quite shady. While I haven't found anything that flowers all summer that's perennial there are some great foliage plants that do well in the shade and flower for part of the growing season. Deadnettle comes in a variety of heights and colours. Some have green and white foliage that really perks up a shady area. Try White Nancy or Beacon's Silver. Barrenwort (epididium--not sure of the spelling) has great foliage that turns red in the fall. There are dwarf hostas that would do nicely in the size patch you describe. Lungwort is another good shade performer. It looks better than the name suggests. It has green foliage with spots of white. These all flower in spring/summer but the foliage brightens up shady areas all season. You might want to consider a mix of these and some ferns.

Jenn - there aren't too many perennials that bloom "most of the summer", especially those that do well in the shade. How about something that has foliage impact, like painted ferns?

Bunchberry (Cornus canadensis) is a pretty compact plant try this site

http://www.thegardenhelper.com/fs~perennials.html?

it'll take you right to what your asking about