The butterfly bush (Buddleia davidii) is a beautiful, fast-growing, deciduous shrub with masses of blossoms—long, spiked trusses—that bloom from summer to autumn. Buddleias need full sun and fertile, well-drained soil. Since they bloom on new wood, even if there is no die-back, cut them back to the ground every spring. Yes, hack to the ground! Even where winters are mild enough for the stems to survive, prune severely to stimulate abundant growth on which flowers are borne.