Trees with white flowers have a way of lifting and lightening a garden’s mood—as well as soothing the mood of the gardener.

"Planting spring flowers not only creates visually ... bloom in early spring and come in an array of white, pink, purple, green and even near-black. She also recommends a moist, well-draining ...

Summersweet ( Clethra alnifolia) blooms in the late summer, says Irish-Hanson, but it's wise to plant it during the spring.