Butterfly bush (Buddleia) is a deciduous flowering shrub that produces colorful blooms and attractive foliage. "The plant features long, arching branches covered with clusters of small, fragrant flowers," says Funk. "The flowers come in various colors, including purple, pink, white, and yellow, attracting butterflies, bees, and other pollinators." It's a dense, fast grower that should be regularly pruned in late winter or spring to ensure it maintains its shape.