Perrenials:

Forget-me-not:  Actually a Bi-ennial flower that spreads rapidly by self seeding and may become invasive if left unchecked.  Blooms May to June and has pink or white flowers  Will grow to 12 inches.  Prefers partial shade or it will not flower long.

Foxglove:  These plants are actually bi-ennials that will reseed themselves quite well.  Foxy is the shorter variety, 2 feet, It has lovely purple white or pink flowers with spots.  Other varieties can grow to 5 feet.  Shade loving plant.  Blooms in late spring to early summer.

Hosta:  This is my favorite shade plant.  Not for the flowers but for the foliage and the plants ability to survive almost anything.  Grows and spreads rapidly reaching a width of about 3 feet.  There a many different varieties and different colors to choose from.  Easy to propagate by division.  Gets purple or white flowers in July.

Iris:  This plant blooms anywhere from early spring to summer, depending on the variety.  They grow from rhizomes or bulbs and form large clumps that can be divided preferably in August.  Bearded Iris (pictured) is my fave and will bloom June to July.  Great for cut flowers.  Anywhere from 6 inches to 4 feet tall.  Folliage is like spears and looks nice all season.

Phlox:  This is a beautiful flower that  ranges from ground cover size to 4 feet high.  Garden Plox (pictured) is my fave, grows 4 feet and spreads fast once established,(about 3 years).  Purple, pink, white, or bi-colored.  Creeping Plox is another popular variety as a ground cover, it doesn't like to be in soggy soil.  Great for rock gardens.  All varieties are easy to divide.

Trillium:  This variety of wildflower is becoming popular in the garden.  Likes shade as is a forest flower.  Can be bought at larger nurseries or maybe if you know someone who might have some growing on there property you can dig  some up.  Blooms in early spring.  Well worth the effort.