Alder buckthorn.

At a glance

Care level

Easy

Plant type

Deciduous shrub

Light

Full sun to partial shade

Indoor light

Bright indirect

Water

Every 5 to 10 days

Mature size

15 feet

Growth rate

Medium

Hardiness

USDA 3 to 8

Bloom time

Late spring to early summer

Care

Keep the soil consistently moist as this plant prefers damp conditions. Watch for yellowing leaves which might signal that the soil is drying out too much. Prune it lightly in late winter or early spring to maintain a nice shape.

Watering

Keep the soil evenly moist but not waterlogged.

Feeding

Apply a balanced fertilizer once in early spring.

Pruning

Prune in late winter or early spring to remove dead wood.

Repotting

Repot only when the plant becomes root bound in its container.

Soil

Moist, acidic, well-draining soil

Soil pH

Acidic to neutral

Temperature

-30 to 35°C

Humidity

40 to 80%

Safety

People

All parts of the plant, especially the bark and berries, are toxic if ingested.

Pets

This plant is considered toxic to pets if ingested, so keep it away from curious cats and dogs.

Children

Keep children away from the berries as they are poisonous if eaten.

Contact allergens

The sap may cause mild skin irritation in sensitive individuals.

Airborne allergens

The pollen is not considered a significant allergen.

Edibility

The berries are considered toxic and should not be consumed by humans.

How to identify it

• Glossy dark green oval leaves
• Small greenish white spring flowers
• Dark purple to black berries
• Smooth gray bark with lenticels

Height

2 to 6m

Spread

2 to 4m

Leaves

green, deciduous

Flowers

greenish-white, 0.5 to 0.8cm

Fruit

red, black, Late summer to autumn

Problems to watch for

• Rust · A fungal infection that causes orange spots on leaves.

Growing it

Propagation

seed, cuttings

When to plant

spring, autumn

Plant in areas where you want to support local bird populations with fruit.

Grows well with

• European Alder · They share similar moisture requirements in wild habitats.

Similar species

• Common Buckthorn · It is a closely related species that is also considered invasive.

Science

Family

Rhamnaceae

Genus

Frangula

Order

Rosales

Class

Magnoliopsida

Native range

Europe, western Asia, and northern Africa.

Conservation

It is considered invasive in some parts of North America, so check local regulations before planting.

It thrives in damp soils and is often found in scrubland or forest edges.

Value to wildlife

nectar source, bird food source

Pollinators

bees

Uses

hedging, wildlife garden, charcoal production

Taxonomy resolved against GBIF.

Questions people ask

Is it invasive?

Yes, it is highly invasive in many North American wetlands and forests.

Does it need full sun?

It tolerates full sun to partial shade.

Where the name comes from

The name Frangula comes from the Latin frangere, meaning to break, referring to the brittle nature of the wood.

Good to know

• It is also known as alder buckthorn.
• The berries change color from red to black as they ripen.
• It is a host plant for the brimstone butterfly in its native range.

Also in

• Plants toxic to cats and dogs