We all love to see butterflies flitting about in our gardens, and that’s why for years the butterfly bush (Buddleia davidii) has been a beloved plant for attracting these winged creatures. Its fragrant, nectar-filled flower spikes in purple, pink, and white are butterfly magnets, just as billed. Though this native of China seemed like a good plant for a pollinator-friendly landscape, it has become a controversial plant for several reasons. Here’s why you may want to reconsider planting butterfly bushes in your garden.
Georgia Parkinson Hill is a horticulturist, garden designer, and owner of the native landscape design firm Beautyberry Gardens in Atlanta, Georgia.
Why Are Butterfly Bushes Bad?
In addition to attracting pollinators, butterfly bushes grow fast, produce flowers early in its life cycle, and grow in tough conditions. All these things are usually desirable for any garden plant. But butterfly bushes have three main drawbacks to note.
Butterfly Bush Is Invasive
Butterfly bushes are officially classified as an invasive plant in at least seven states (North Carolina, Maryland, Oregon, Washington, Pennsylvania, Virginia, and New Jersey) and are considered an emerging threat in several more states, including Ohio and Tennessee. Oregon and Washington have listed butterfly bush as a Class B noxious weed, and Oregon has partially banned its sale.
Experts say butterfly bush can be invasive almost anywhere because it produces a lot of seeds that spread by wind and water. This has caused butterfly bushes to escape cultivated yards or gardens, take root in the wild, and outcompete native plants that provide food and habitat for native insects, birds, and other wildlife.
“I really love the smell of butterfly bushes,” says Georgia Parkinson Hill, a horticulturist, garden designer, and owner of Beautyberry Gardens in Atlanta, Georgia. “It reminds me of my home in the United Kingdom, where it’s badly invasive. But since they’re so invasive, I’m not a fan of them.”
Less Nutritious Nectar
Butterfly bush nectar is high in sugar and low in other nutrients butterflies need to thrive. It gives butterflies a quick hit of energy, instead of the more balanced meal that the insects could get from plants like coneflowers, Joe-Pye weed, and bee balm. Butterfly bush nectar isn’t bad for butterflies. It’s just not very good for them, either. Butterfly bush nectar is to butterflies what sugary soda is to humans.
Not a Host Plant
Host plants provide essential food and shelter for baby butterflies, aka caterpillars. A good butterfly host plant, like milkweed or passionflower, attracts adult female butterflies to lay eggs on the plant and then provides specific nutrients to help the caterpillar grow and transform into a butterfly.
“Host plants are critical to the life cycle of butterflies,” Hill says. “Butterfly bushes are a nectar plant, but they are not a host plant.” That means butterfly bushes don’t help most North American butterfly species reproduce; they just give the adults a quick meal of nutrient-poor nectar.
“Butterfly bushes outcompete native plants that are hosts to butterflies,” Hill says. “They provide the wrong kind of environment for the butterflies.”
What to Do About Butterfly Bushes
If you’ve already got a butterfly bush or two in your yard, should you dig it up? “I don’t unless a client wants me to,” Hill says. “I don’t suggest them when I’m planning a landscape, either.” However, if you’re growing an older type that reseeds prolifically, and it is considered invasive in your area, you may want to dig up your butterfly bush and replace it with something less problematic.
Otherwise, if you still want to grow a butterfly bush, here are a few ways to minimize its negative aspects:
Choose Less Invasive Varieties
There are newer varieties of butterfly bushes that bred to produce fewer seeds, so they’re less likely to escape into wild areas. They’re marketed as sterile or low-fertility varieties and they tend to be compact plants that take up much less space than standard butterfly bushes. Keep in mind, these cultivars may still produce pollen that could fertilize more invasive butterfly bushes nearby.
Less-invasive butterfly bush cultivars include the Pugster series from Proven Winners, which offers full-sized flowers on a compact plant; as well as the Lo & Behold series and the ‘Miss’ series. ‘Asian Moon’ is a taller variety of butterfly bush with white flowers that is reported to have low seed production too.
Add More Butterfly Host Plants
Another way to lessen the impact of butterfly bushes is to plant host plants for butterflies in your yard as well as a butterfly bush. That way, you provide habitat for many butterflies and moths, including the ones native to North America.
A few recommended host plants include:
- Milkweed (Asclepias spp.), the host plant for the monarch butterfly
- Parsley, dill, golden Alexander (Zizia aurea), and fennel, the host plants for the black swallowtail butterfly
- Passionflower (Passiflora spp.), the host plant for the Gulf fritillary butterfly
- Pipevine, also known as Dutchman’s pipe (Aristolochia macrophylla), host plant for pipevine swallowtails
- Spicebush (Lindera benzoin) and sassafras (Sassafras albidum), hosts for spicebush swallowtails
By planting lots of different pollinator-friendly plants, you’ll not only give butterflies and other winged creatures vital host plants, but also a buffet of nectar. With all these plants, Hill says, “You can build out a habitat that’s much better for butterflies than a butterfly bush.”