Gardener Warned About Aggressive Pollinator Plant: 'Cut It Back Before It Seeds'

Planting flower species that are native to North America is a popular option for gardeners, and for good reason. They're naturally adapted to local climates, provide food and habitat for wildlife, and generally require less maintenance than other plants. There's even a long list of native plants that provide a sustainable way to attract hummingbirds to your home. Among the species that stand out for both its beauty and its impact is late boneset (Eupatorium serotinum). Its tall stems support clusters of white flowers that bloom late in the season, attracting a variety of pollinators. Bees, butterflies, and moths visit these blossoms when other nectar sources are gone, making late boneset a valuable addition to support late-season pollinators. Gardeners often praise the flower for its delicate appearance and the visual interest it brings to meadows, borders, or naturalized garden spaces. Its late blooming cycle complements early and mid-season flowering plants, extending the period of color and pollinator activity in the garden.

One of the notable drawbacks that may deter gardeners from choosing the late boneset is that it is highly aggressive. The plant self-seeds freely, sometimes establishing dense colonies that compete with neighboring plants. Without intervention, gardeners have reported that it can spread well-beyond intended boundaries, crowding out more delicate native plants and even ornamentals. Because of this, it is essential to manage the growth of the late boneset to ensure  they don't overrun your pollinator-friendly garden.

If you want to grow this plant successfully, it will require effort and vigilance. This perennial thrives in full sun to partial shade and prefers moist soil that is sandy or clay-like, although it adapts well to drier conditions when watered properly. Avoid the common garden watering mistake of completely soaking the soil, as you don't want it to become stagnant. Late boneset is a deer-resistant plant, which can help to protect neighboring plants. Its abundant seeds can also attract a number of local birds to your garden.

Controlling its aggressive nature is key to enjoying the late boneset responsibly. Deadheading spent blooms before seeds are produced is the simplest strategy to prevent spreading. Some gardeners trim the plants by half in mid-spring, encouraging bushier growth while limiting seed dispersal. Containment within raised beds or naturalized areas can further prevent it from crowding other species that may be vulnerable to resource competition. Mulching around the base and promptly removing unwanted seedlings will ensure it does not establish beyond intended areas. If colonies do expand, dividing and transplanting plants is an option, but it can be a labor-intensive process. Vigilant monitoring, combined with regular pruning and the removal of stray seedlings, allows gardeners to benefit from late boneset's ecological and aesthetic contributions without letting it dominate your landscape.