For background shrubs, consider Boxwood 'Green Velvet' or Blue Holly 'China Girl. In front of these evergreen shrubs, you could do a perennial garden which would give you lots of color throughout the season.
Here are some perennials and shrubs that you could add...in groups of 3 to five each. Try to differ the textures of the plants that are next to each other.
Fairy Rose
Nepeta 'Walker's Low' - long lasting purple flowers
Lavender 'Hidcote'
Coneflower - many colors to choose from
Black Eyed Susan
Annabelle Hydrangea - part sun, part shade
Endless Summer Hydrangea - part sun part shade
You could also add a few Red Barberry if you like shrubs with red foliage.
One thing I would comment on...the dwarf Japanese Red Maple. Although people seem to like this plant, it never really makes a statement and is rather weak. I would use a large ornamental tree at the left house corner. How about the Japanese Maple 'Bloodgood', which has a beautiful shape and leaves that stay red all season? A Flowering Dogwood or a Birch tree would work also.
You could also add another tree near the front door on the other side of the walk. I always find trees welcoming as you approach the entry of the house.
I hope this was helpful.
Susan
May 11, 2009 Rating
Adding Info by: Brian
I should also mention that we are in northern Delaware, not sure what zone that is... but I think we're on a line. Also, I'm looking to do something that will provide color throughout as much of the year as possible. Thanks!