One of the latest of the late bloomers, balsam aster (Aster ageratoides) is a true aster native to eastern Asia. The plants grow vigorously into bushy 3-foot plants with small, dark-green, toothed leaves. In October and into November, they are topped with intense violet buds that slowly open to reveal contrasting yellow centers. When fully open, the flowers become lavender. As a late bloomer into November, balsam aster is a good plant for pollinators.