For 3 months in the heat of summer, crape myrtles display dense cloudlike flower panicles in white, pink, purple, or red, and even a single tree can have the appearance of a grove since multiple trunks are the norm. Young crape myrtles are vigorous and upright, with satin-smooth bark, but the older they get, the more deeply distinguished the graceful trunks become. In summer, the paper-thin bark peels away, exposing polished, mottled trunks. Crape myrtles need hot summers to flower best. Selemon says crape myrtle cultivars planted in Seattle didn't flourish until they were moved to a parking-lot island, where the reflected heat brought them promptly into glorious bloom. Many cultivars have wonderful fall color. Most crape myrtles grow 15 to 25 feet tall. Hardy in Zones 7 to 9; grows as a dieback plant in colder areas.