Is Butterfly Bush Really That Bad?

By Jade Greene

Whenever I tell someone that butterfly bush (Buddleia davidii) is bad, they don’t want to believe it. I’ve heard it over and over again – butterfly bush can’t be bad, it attracts so many butterflies! It’s so pretty! It smells amazing! Just look at all the butterflies on it! 

I am the curmudgeon – yes it is really that bad. Here’s why:

• It is invasive: indigenous to Asia, the plant was introduced here as an ornamental but has escaped gardens and is invading wild spaces. A single butterfly bush FLOWER can produce 40,000 seeds so it spreads very easily. The plant does not have any organisms that eat it so it can get out of control. Once established, butterfly bushes outcompetes native shrubs and flowers. It is considered a noxious weed in some states. 

• It does not provide food for caterpillars: there are no native butterflies and moths that use butterfly bush as a host plant for their caterpillars. That means adults can get a snack on some nectar but can not lay eggs. Compare that to Golden Alexander (Zizia aurea) which provides nectar and a place for swallowtail butterflies to lay eggs and feed their caterpillar offspring.

• Side note, why is the lack of caterpillars a problem? Besides making it harder for butterflies to reproduce in the next generation, it also harms birds. If you attended Nature’s Best Hope, you know providing bird seed for adult birds is not enough, you also need to provide caterpillars so they can rear their young (most baby birds do not eat bird seed). It takes 10,000 caterpillars to rear one clutch of chickadees! By planting plants that caterpillars eat, you are also making food for chicks.

• It provides low nutrition nectar for butterflies: as mentioned, butterfly bush originates from Asia where it is a nutritious source of nectar to Asian butterfly species. Here in North America, its nectar is not as nutritious as a native flower. Its nectar is akin to a bag of chips rather than a salad.

Instead of butterfly bush, try planting one of these wonderful native plants that will provide nutritious nectar, beautiful blooms, caterpillar food, and benefit other pollinators:

• Goldenrod (perennial flower)
• Asters (perennial flower)
• Golden Alexander (perennial flower) 
• Milkweed (perennial flower)
• Blueberry (shrub)
• Arrowwood viburnum (shrub) 

If you have a butterfly bush and are not ready to remove it. Try to deadhead (cut off the flowers) before they go to seed. This will help prevent the spread of the plant to wild spaces around your yard.

Further reading and sources:

• https://extension.psu.edu/avoiding-invasives-butterfly-bush 
• https://gardenforwildlife.com/blogs/learning-center/why-to-avoid-butterfly-bush 
• Tallamy, Douglas W.. Nature’s Best Hope: A New Approach to Conservation That Starts in Your Yard. Timber Press, 2019.