Tall plant or shrub for back of shade garden
I have a fairly large shade garden (approx. 20'x20'), kind of a semi-circular shape and have left room in the back center for a large plant or shrub. Now I just need help deciding what to plant there! The area is under maple trees but gets some dappled sunlight throughout the day and there's open sky on the north side. We're zone 4 but are pretty sheltered because of the maple trees and get a lot of snow. The soil is pretty sandy but has been amended with a couple yards of Dairy Doo.
I would like something that provides a lot of visual interest all season long. I am considering the Golden Shadows Pagoda Dogwood or possibly mountain laurel. Any comments about either of these or alternate suggestions would be appreciated.