You can keep the landscape simple and still repeat the curve of your windows by adding a weeping Japanese maple to the landscape either in a new bed or in front of the white panels in the front. The red leaves of a Japanese maple can be contrasted with gold foliage from golden nugget dwarf barberry and low growing black mondo grass. Color from foliage rather than flowers is easier to maintain. Consider some large weather resistant containers planted with evergreen shrubs as well. Keep growing, Marianne Binetti