Butterfly Bush: Potential Invasiveness and Tips for Selection and Care

The butterfly bush has become a favorite for gardeners due to its large, eye-catching flowers and its ability to attract butterflies and pollinators. This explains why it’s commonly known as the butterfly bush, rather than its scientific name, Buddleja davidii.

With proper sunlight, this perennial is easy to grow and provides stunning blooms in various colors such as red, pink, white, yellow, blue, or purple. However, while popular, butterfly bushes can be problematic in certain areas. Discover why you may want to reconsider planting it and how to properly choose and care for a butterfly bush if you decide to add it to your garden.

Is a Butterfly Bush Right for Your Garden?

Who wouldn’t love a plant that draws butterflies into their garden? It’s a wonderful way to promote pollination and enhance the beauty of your space. However, depending on where you live, it’s wise to research before planting the butterfly bush.

Butterfly Bush: Potential for Invasiveness or Restrictions

Depending on your location, the butterfly bush may be restricted or invasive. According to plant expert Tamara Hogan, "Some areas, like the Eastern US (North and South) and Pacific Northwest, consider butterfly bushes to be invasive species." It could also be semi-invasive in states surrounding the Great Lakes.

Hogan notes that the butterfly bush is best suited for the Intermountain West, Central US, and Southwest, where environmental conditions limit its spread. Both Washington and Oregon ban the planting of butterfly bushes, except for certain seedless varieties, sometimes referred to as 'summer lilacs.'

Butterfly Bush: Poor Nectar Quality

One downside of the butterfly bush is that it's a bit like fast food for plants—visually appealing but lacking substance. As Hogan points out, "While they attract butterflies and other pollinators due to their flower shape and color, the overall quality of their pollen and nectar is relatively low."

"If you choose to plant butterfly bushes, it's important to pair them with other plants that provide a better environment for pollinators, such as coneflowers, liatris, salvias, and asters. This not only attracts pollinators but also helps nourish them and keep them in your garden," Hogan advises.

Selecting a Non-Invasive Butterfly Bush

Even in areas where the butterfly bush is considered invasive, there are safer options to plant. Consider choosing dwarf varieties, which are less prone to invasiveness, or specially engineered sterile versions that are unlikely to spread.

Hogan recommends varietals like Lo and Behold 'Blue Chip' and Pugster Pink when selecting a butterfly bush. Additionally, make sure to research the full mature size of the plant to ensure there’s enough space for it. Hogan advises, "If you're planting a bush that can reach up to [six] feet tall and wide, it's best to plan accordingly for that size when planting."

Proper Care for a Butterfly Bush

If you decide to plant this popular perennial, proper care is essential. Find a location with the ideal conditions for it to flourish. Here's what you need to know:

Ensure Sufficient Sunlight

The butterfly bush thrives in full sunlight, so choose a spot that receives six to eight hours of sunlight each day. "If it gets less than that, the plants may become 'leggy' as they stretch toward the light," says Hogan. "This can result in elongated leaves and plants growing at an angle toward the sun."

Steer Clear of Wet Areas

Butterfly bushes prefer soil that drains well, so avoid planting them in areas prone to lingering moisture after rainfall. (They’re not a good fit for a rain garden.) Excessive moisture can cause root rot in your butterfly bush.

Water Properly

Think of the butterfly bush as the "Goldilocks" of your garden—neither too dry nor too wet. Make sure to check the soil before watering and only water when needed. To avoid fungal infections, water the butterfly bush in the morning or earlier in the day to prevent moisture from sitting on the leaves for too long.

Prune Regularly

Pruning your plants in spring after new buds appear can help protect your butterfly bush from winter damage. Remove faded blooms before they can seed to prevent your butterfly bush from spreading. (By removing spent flowers, you’ll also encourage new blooms on your butterfly bush.)

Watch for Pests and Diseases

The butterfly bush is fortunate in that it rarely succumbs to diseases or pest infestations. If you do notice any pests, rinse them off with a gentle spray of water. Avoid using pesticides, as they can harm the beneficial pollinators that frequent the butterfly bush.

Frequently Asked Questions

• Do butterfly bushes return every year?

  As a perennial, the butterfly bush will come back each year after appearing to "die" in winter. In reality, the plant simply goes dormant during the colder months, and you’ll see fresh growth emerge once spring arrives.

• How tall does a butterfly bush grow?

  Standard butterfly bush varieties can reach a height of five to 10 feet, while dwarf varieties typically grow between two to four feet. Because of this, it’s important to choose a spacious location for planting.

• What is the lifespan of a butterfly bush?

  On average, a butterfly bush lives for about 10 years, though some may last longer, but that's uncommon. Proper care can help extend its life and ensure it thrives in your garden.