Scotch Broom: A Beautiful but Problematic Non-Native Shrub
If you’ve ever driven through the Pacific Northwest in late spring and noticed hillsides covered in brilliant yellow blooms, you’ve likely encountered Scotch broom (Cytisus scoparius var. scoparius). While undeniably eye-catching, this European import has become one of North America’s most challenging invasive plants.
What is Scotch Broom?
Scotch broom is a perennial shrub that typically grows 4-5 meters (13-16 feet) tall, though it can reach greater heights under ideal conditions. This multi-stemmed woody plant is also known by its scientific synonym Sarothamnus scoparius. Originally native to western and central Europe, it has established itself far beyond its homeland.
Where Does Scotch Broom Grow?
This non-native species has spread extensively across North America, reproducing spontaneously in the wild without human intervention. You’ll find established populations across a remarkable range of locations, including Alabama, California, British Columbia, Nova Scotia, Prince Edward Island, Connecticut, Delaware, District of Columbia, Georgia, Hawaii, Idaho, Kentucky, Maine, Maryland, Massachusetts, Michigan, Montana, New Hampshire, New Jersey, New York, North Carolina, Ohio, Oregon, Pennsylvania, South Carolina, Tennessee, Utah, Virginia, Washington, and West Virginia.
The Appeal and the Problem
It’s easy to understand why Scotch broom initially appealed to gardeners and land managers. The shrub produces masses of bright yellow, pea-like flowers in spring that create stunning displays. Its green, angular stems remain attractive even when not in bloom, and the plant thrives in poor soils where other plants struggle.
However, these same hardy characteristics make Scotch broom a formidable invader. It grows rapidly, tolerates drought, and produces thousands of seeds that can remain viable in soil for decades. The plant also fixes nitrogen, changing soil chemistry in ways that can disadvantage native plants.
Growing Conditions and Hardiness
Scotch broom adapts to a wide range of conditions, which contributes to its invasive success. It prefers:
- Full sun exposure
- Well-draining soils (tolerates poor, sandy, or rocky conditions)
- USDA hardiness zones 5-9
- Low to moderate water once established
Wildlife and Pollinator Considerations
While Scotch broom flowers do attract bees and other pollinators with their nectar, the plant’s overall impact on native ecosystems is negative. Dense stands can crowd out native plants that provide more diverse and appropriate food sources for local wildlife throughout the growing season.
Should You Plant Scotch Broom?
Given its invasive nature and tendency to escape cultivation, we strongly recommend against planting Scotch broom. Even where it’s not officially listed as noxious, this species can quickly become problematic and difficult to control.
Native Alternatives to Consider
Instead of Scotch broom, consider these native alternatives that provide similar aesthetic benefits without the ecological risks:
- Spicebush (Lindera benzoin) – offers yellow fall color and supports native butterflies
- Native azaleas and rhododendrons – provide spectacular spring blooms
- Serviceberry (Amelanchier species) – beautiful flowers and berries for wildlife
- Native viburnums – diverse species with flowers, fall color, and wildlife value
If You Already Have Scotch Broom
If Scotch broom is already established on your property, consider removal and replacement with native alternatives. Small plants can be pulled when soil is moist, while larger specimens may require cutting and treating stumps to prevent regrowth. Always dispose of plant material properly to prevent spread.
While Scotch broom’s golden blooms may be tempting, choosing native alternatives will create a more sustainable and ecologically beneficial landscape that supports local wildlife and preserves natural plant communities for future generations.
