shrub

Common Buckthorn

Rhamnus cathartica

The Story

Plant Bio

Rhamnus cathartica, commonly known as common buckthorn, is a vigorous deciduous shrub or small multi-stemmed tree native to Europe and western Asia. It features a spreading, rounded crown of dark glossy green leaves and twigs that frequently terminate in sharp, stout thorns.

This species is highly distinguished by its phenology, leafing out earlier in spring and retaining its green foliage much later into fall than native North American deciduous plants. In North America, it has become a highly invasive noxious weed that forms dense, monotypic thickets in forest understories.

Uses & Benefits:

Provides a dense, glossy green screen or hedge, though its ecological damage outweighs its ornamental value.

The sharp terminal thorns make it an effective physical barrier or security hedge.

Provides nesting cover for birds, though the berries act as a severe laxative and aid in its invasive spread.

Essentials

At a Glance

Plant Type

Shrub

Height

300"

Width

157"

Light

Full Sun, Partial Sun

Zones

4, 5, 6, 7

Water

Moderate

Humidity

Moderate

Lifespan

Perennial

Native To

Europe, northwestern Africa, western and central Asia

Toxicity

Toxic to humans and animals if ingested; thorns cause puncture wounds

Bloom period

Spring

In flower about 3 months of the year

Planting

How to Grow

Select a site with full sun to partial shade and well-drained soil, ensuring local regulations permit cultivation.
Sow stratified seeds in spring or plant softwood cuttings in a prepared bed.
Monitor the plant closely to prevent self-seeding into nearby natural areas.
Prune in late winter to remove dead or crossing branches, avoiding shearing into old wood.

Pro Tip

Identify and target buckthorn in late fall when native species have dropped their leaves; cut the stems close to the ground and immediately apply a systemic herbicide to the stump to prevent aggressive resprouting.

Keep It Thriving

Care Guide

Do

Wear thick gloves when handling to protect against sharp thorns.
Check local noxious weed lists before planting or maintaining.
Remove female plants first to minimize seed production and dispersal.

Don't

Do not allow berries to drop and spread into adjacent woodlands.
Do not ingest any part of the plant, as the berries and bark are highly toxic.
Do not shear the outer foliage, which results in patchy, weak regrowth.

Seasonal Care Calendar

Task	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Pest Check
Propagate
Prune
Spring Cleanup

Watch Out For

Pests & Diseases

Common Pests

Common Diseases

In the Garden

Landscape Uses & Companions

Landscape Uses

HedgeWindbreakBarrier Planting

Multiply

Propagation Methods

Good to Know

Common Questions

Common Buckthorn questions

What zones can Common Buckthorn grow in?

Common Buckthorn is hardy in USDA Zones 4–7. Inside that range it survives winter in the ground; outside it, grow it as an annual or a container plant you protect.

When does Common Buckthorn bloom?

Common Buckthorn typically blooms in spring through spring. Exact timing shifts a week or two with your zone — Sow's bloom calendar maps it to your garden.

Does Common Buckthorn need full sun?

Common Buckthorn does best in full sun to part shade. In hot climates, afternoon shade keeps blooms fresher longer.

Is Common Buckthorn drought tolerant?

Yes — once established (usually after the first full season), Common Buckthorn handles dry spells with minimal watering. Water deeply its first year to build the root system that makes that possible.