Vol. 18 Issue 2, Summer 2013
by Emily Cook
The butterfly bush, Buddleia davidii, is a staple, and often the centerpiece, of many local area gardens. Known for its ability to grow in almost intolerable conditions and still produce vibrant, fragrant, cone-shaped blossoms, this plant is a real workhorse and truly lives up to its name — it attracts butterflies, hundreds upon hundreds of them, all summer long. As the proud owner of a “Black Knight” butterfly bush, I can attest to this plant’s magical allure when it comes to drawing everything from Monarchs to swallowtails to delicate fritillaries and tiny skippers. Yet, after years of enjoying the magical dance of butterflies fluttering around the butterfly bush’s vivid, deep purple flowers, it may be time to bid adieu to this non-native import. It has not only become a nuisance to local native plants but also to the butterflies themselves.
The butterfly bush has been the go-to plant for naturalizing gardens for years. Those wishing to draw butterflies of every variety to their yards toss the plants in the ground and provide them very little care. In return, the bush would grow rapidly and aggressively, creating a veritable butterfly farm. In fact, it performs its duty so well, it is sometimes covered with more butterflies than blossoms. The insects’ fluttering seeming almost rhythmic as butterflies dance from flower to flower, skipping over one another in a flurry of wings. But it is the Buddleia’s hardy, resilient quality as well as the abundance of seeds the plant produces that are the problem. This beautiful bush can grow virtually anywhere and in seemingly impossible conditions, resulting in the plant becoming highly invasive.
A native to Asia and Central America, the seeds of the butterfly bush spread easily. Plants native to the United States are often unable to thrive in areas where butterfly bush has taken root because they lack natural predators and quickly dominates the landscape. This rapidly growing plant can also grow from even the smallest cuttings or trimmings, making it difficult to contain in even the worst growing conditions. The result is a proliferation of butterfly bush in areas such as stream and riverbanks, roadsides, and other naturalized areas, and a gradual decrease in the number of native plants on which butterflies, birds, bees and other insects depend. In addition, these foreign plants are not able to meet the nutritional needs of our local birds and insects. Nor do they serve as a host plant to any butterfly caterpillars, thus impacting the reproductive cycle of many of the insects we are trying to attract.
The butterfly bush is considered invasive in 25 states, several of which are in the Mid-Atlantic region. In Pennsylvania and Virginia, buddleia is considered prolifically invasive. The sale of all varieties of buddleia has been banned in the state of Oregon. Several states are battling serious infestations including New Jersey, whose native dune vegetation is being choked out by an overgrowth of butterfly bush, and Pennsylvania’s Pocono River banks, which are heavily blanketed with the plants for miles.
So what should you do if you want to attract butterflies and love the look of the buddleia’s abundant, vibrant blooms? There are plenty of options and some encouraging news for those of us who are almost in tears at the thought of removing buddleia from our gardens. In recent years, new seedless cultivars of Buddleia have been developed that come in a wide range of colors and do not pose the same risk as their seeded siblings. However, should you opt to incorporate the seedless variety into your landscape, you should still take precautions when cutting and trimming to ensure the remnants are contained and unable to take root elsewhere.
Better yet, if your goal is to both attract and provide a haven for butterflies and other insects and birds in your yard, it would be wise to introduce some plantings that are not only a food source to local insects and wildlife but also serve as a host plant to butterfly caterpillars. It is important to note that the Buddleia, even the new, seedless variety, does not provide the necessary environment for the eggs and newly hatched caterpillars. Therefore, it should be used in limited quantities, if at all. Some native options that would truly benefit the butterfly population and its life-cycle include the Common Milkweed (Asclepias syriaca), Swamp Milkweed (Asclepias incarnata), and Butterfly Weed (Asclepias tuberosa). All of these produce beautiful blooms from June through early fall and will become a breeding ground for many varieties of butterflies, while protecting our environment and local vegetation.
Buddleia: Seedless Butterfly Bush: portlandnursery.com/plants
Butterfly Bush Beware: www.birdsandblooms.com/blog
Blue Chip Butterfly Bush: www.thespruce.com
Native alternatives to Butterfly Bush: www.nps.gov/plants