Common buckthorn (Rhamnus cathartica)
Rhamnus cathartica, or Common buckthorn, is a fast-growing deciduous shrub noted for its adaptability and dark berries attractive to birds.
Complete Plant Information
Overview
Rhamnus cathartica, widely known as Common buckthorn, is a densely thicket-forming deciduous shrub or small tree. While historically used decoratively, its aggressive nature means it demands attention in modern landscapes. This plant is valued for its rapid growth rate, allowing it to quickly fill in spaces or establish screens, though this speed contributes significantly to its weedy status.
The bark of Rhamnus cathartica is grayish-brown, revealing distinctive yellow inner bark and orange heartwood which adds subtle winter character. This Common buckthorn produces small, inconspicuous flowers followed by fleshy black drupes, which are highly attractive to many bird species, aiding in its prolific naturalization. It thrives across USDA Zones 3 through 8 under varied light conditions.
Adaptability is a key feature of Rhamnus cathartica, as it tolerates a wide range of soils and moisture levels once established. However, gardeners should be aware that this species is considered invasive in many regions due to its efficient self-seeding habit, producing dense stands that can displace native understory flora.
Fast Facts
- Plant Family: Rhamnaceae
- Plant Type: Deciduous shrub
- Native Range: Temperate Europe and Asia, northwestern Africa
- Hardiness Zones: USDA Zones 3-8
- Size at Maturity:
- Height: 16-25 ft
- Spread: 10-15 ft
- Bloom Time: April to June
- Bloom Description: Yellow-green
- Sun Exposure: Full sun to part shade
- Water Needs: Medium
- Maintenance Level: Medium
How to Grow
Planting Common buckthorn is best done in spring or early fall when the plant can establish roots before facing temperature extremes. This species adapts well to average, medium-moisture, well-drained soils. It performs well in both full sun and partial shade conditions, though consistency in moisture is preferred for optimal establishment.
Maintenance for Rhamnus cathartica is relatively low, reflecting its hardy nature. While it prefers consistent moisture, it is generally drought-tolerant once mature. Fertilizer is rarely necessary given its tolerance for various soil types. Pruning is primarily required to control its shape or remove suckers if using it as a formal screen or hedge.
A critical note on care involves managing its tendency to become a troublesome self-seeder. Because the leaves retain their green color late into the fall, this shrub often provides late-season interest but also extends the window for birds to disperse its berries. This fast-growing nature means that rigorous monitoring and removal of seedlings are essential maintenance tasks.
Landscape Uses
Historically, Common buckthorn was installed for practical landscape functions due to its dense, fast-growing habit. It served adequately as an informal hedge, a robust privacy screen against property lines, or a windbreak in open areas. It could also act as a backdrop for taller perennial plantings where quick structure was needed.
However, modern ecological stewardship strongly discourages planting Rhamnus cathartica. If you are seeking vertical structure or hedging, superior native alternatives exist that provide similar screening benefits without the risk of ecological damage associated with this aggressive species. Where it is currently established, focus efforts on thoughtful removal rather than new installations.
Standout Features
Flower Qualities
- Insignificant
Noteworthy Characteristics
Rhamnus cathartica, commonly called common or European buckthorn, is a weedy, thicket-forming, deciduous shrub or small tree that typically grows to 16-25’ tall. It is noted for having small spines at the branchlet ends. Elliptic, dark green leaves retain their color long into fall before turning yellow, and the fruits are highly attractive to birds.
Tolerances
- Tolerates a variety of soils and environments
Potential Problems
Common buckthorn is widely classified as an invasive exotic species across much of eastern North America, presenting significant management challenges. Its spread is extremely rapid, primarily due to prolific self-seeding; bird-dispersed seeds germinate thickly beneath parent plants, creating dense, impenetrable thickets the following season.
These colonies quickly out-compete and physically displace desirable native flora in forests, fields, and roadsides, severely reducing local biodiversity. Eradication once colonies are established is difficult and often requires intensive effort involving mechanical removal and chemical treatment. Furthermore, this buckthorn can serve as an alternate host for the crown rust of oats in agricultural areas. Regular scouting for and immediate removal of seedlings is the best preventative measure against wide-scale infestation.
Frequently Asked Questions
What hardiness zones is Common buckthorn suitable for?
Rhamnus cathartica is adaptable across a wide range, thriving in USDA Zones 3 through 8.
How large does Rhamnus cathartica grow?
This deciduous shrub typically reaches a mature height between 16 and 25 feet, with a spread ranging from 10 to 15 feet wide.
What sun exposure does Common buckthorn need?
It is tolerant of varied light, growing well in spots ranging from full sun exposure to areas of partial shade.
When does Rhamnus cathartica bloom?
The small flowers appear between April and June, displaying a yellow-green coloration before developing into dark, berry-like fruits.
Conclusion
Despite its initial utility as a hardy, fast-growing screen, the aggressive invasive tendencies of Rhamnus cathartica significantly outweigh its aesthetic value in modern gardening. Responsible land management requires avoiding the planting of Common buckthorn and prioritizing the removal of existing invasive patches. Always confirm local ecological guidelines before introducing any new shrub into your landscape.
Wildlife Benefits
The fleshy, black drupes produced by the female Rhamnus cathartica plants are a critical late-season food source for many bird species. Birds consume the berries readily, and because the seeds pass through their digestive systems unharmed, they are efficiently scattered across wide distances, contributing to the rapid spread of this shrub.
While providing food, the dense thickets formed by this species can offer excellent cover and nesting habitat for common birds. However, this benefit must be weighed against the displacement of native shrubs that provide superior nutritional value and structure for local wildlife populations.
Seasonal Care Calendar
Spring is the ideal time for management actions concerning Common buckthorn. Focus on removing seedlings identified from the previous year’s seed drop, cutting them out when young before roots become deeply established. This interrupts the cycle of self-seeding that characterizes this species.
During the summer growing season, monitor established plants for any suckering or uncontrolled growth, especially if they were previously planted for screening purposes. Pruning back errant branches helps maintain control, although mature removal often requires cutting the main stems close to the ground.
In the fall, observe leaf color change, noting that the leaves of Rhamnus cathartica turn yellow later than many native deciduous plants. This late foliage presence can mask seedling germination, making diligent inspection in early spring and late fall crucial for early detection of new invaders.
