shade perennials?

shade perennials?

Speak to me, my gardening friends, of your favorite shade perennials viable in Zone 4 (avg. annual lowest temp is -20 to -25 F, or -29 to -32 C). I'm in college for Horticulture, and our semester project for Perennials class is designing a planting plan for a huge woodlot area that's mostly part to full shade. I do not want to do the ordinary thing and use a ton of hostas. Bonus points if the plant has white/cream, blue/purple or yellow flowers, but I'm open to foliage plants and ferns and such as well.
Help with tomatoes?

Help with tomatoes?

Oh, the conundrum….

Oh, the conundrum….

help! weeds?!

help! weeds?!

Help! Organization issues!

Help! Organization issues!

Spring!

Spring!

oh dear…

oh dear…