The Butterfly Bush (Buddleia davidii) is a beautiful, fast-growing deciduous shrub with masses of blossoms—long, seductively spiked trusses—that bloom from summer to autumn. The flowers come in many colors, though butterflies prefer the lavenderpink (mauve) of the species to the white and dark purple cultivars.
It is hardy to zone 5 and remains evergreen from zone 8 south. The shrub is also low-maintenance, only required dead-heading and annual pruning in later winter to encourage flowers and a compact shape.
Please note that the popular Butterfly Bush, imported from China, is now being classified as an invasive in most regions, which means it’s crowding out native food that is essential to wildlife, including butterflies and birds. In more gentle climates, it can become a noxious weed. In other climates, it seems to stay contained within a garden’s cultivated soil if gardeners deadhead the flowers once spent.
Also, despite the “butterfly” name, keep in mind that this shrub is not a “host plant” for butterflies in that it does not support butterfly reproduction and lifecycle. Rather, it provides nectar to adult butterflies; think of nectar as their favorite adult beverage! If you do have a Butterfly Bush, be sure to add native host plants such as milkweed if you want the butterflies to stay. See plants that attract butterflies.
There are non-invasive American Butterfly Bushes. Please check with your local cooperative extension for more information.