Japanese barberry

Sun

Full sun to partial shade; foliage colour is usually strongest in sun, although some yellow-leaved cultivars scorch in hot afternoon sun.

Water

Water regularly during establishment; established plants tolerate moderate drought. Avoid persistently wet soil.

Soil

Most well-drained soils, including clay, sand and chalk; tolerates acidic to alkaline conditions.

Height

3-6 ft (0.9-1.8 m); dwarf cultivars remain smaller

Spread

4-6 ft (1.2-1.8 m); varies considerably by cultivar

Flowers

Small, pale yellow flowers in mid- to late spring, followed by red berries.

Foliage

Small, rounded to spoon-shaped leaves; green in the species, with purple, red and yellow cultivars. Autumn colour ranges from orange to scarlet.

Growth

Moderate

Care needed

Low

• Pollinators
• Deer resistant
• Drought tolerant
• Cold hardy
• Wildlife
• Low allergen

Northern hemisphere months. In Australia, shift them by six.

Difficulty

Easy

Toughness

Very tough

Pick your zone, country, light and whether you have pets.

1. Planting day

   1.6 ft (0.5 m)

2. After 1 year

   2.2 ft (0.67 m)

3. After 2 years

   2.8 ft (0.84 m)

4. After 3 years

   3 ft (1 m)

5. After 5 years

   4 ft (1.4 m)

   full size

About 5 years to full size.

From a typical nursery size, at an average rate for this kind of plant. A rule of thumb, not a forecast.

Cats and dogs

Mildly toxic: may upset a stomach

Invasive in

the US and Canada

In the garden

Spreads vigorously: plan to contain it.

Growth rate

Moderate

• Check local invasive-species advice and sale restrictions before buying or propagating.
• Water deeply during dry spells in the first growing season; thereafter water during prolonged drought.
• Apply a 2-3 in (5-8 cm) mulch layer, keeping it clear of the stems.
• Do not feed routinely; use a light spring feed only if growth is weak and soil fertility is low.
• Wear thick gloves when handling or pruning, and keep thorny branches away from paths.

Pruning. In late winter, remove dead, damaged or crossing stems and cut selected old stems to ground level if renewal is needed. Trim hedges after flowering, accepting that clipping reduces flowers and berries.

Late winter

Remove damaged stems and thin congested growth before leaves emerge.

Spring

Where planting is appropriate and legal, plant into well-drained soil and water thoroughly.

Late spring

Trim established hedges after flowering; inspect young shoots for aphids.

Summer

Water newly planted shrubs during dry weather and check for leaf scorch or mildew.

Autumn

Look for seedlings beneath the shrub and nearby bird perches; remove them before they establish.

Late autumn

Top up mulch if needed, leaving a clear gap around the stems.

• Where non-invasive and permitted, use as a clipped boundary hedge away from pedestrian routes.
• Use compact cultivars as low edging in formal beds, allowing room for their thorny spread.
• Contrast purple-leaved cultivars with silver foliage and ornamental grasses in sunny mixed borders.
• Use green-leaved forms for autumn colour among shrubs with quieter summer foliage.

Garden styles it suits: Formal, Traditional, Modern courtyard, Autumn colour, Low-maintenance and Japanese.

Plant it with: Catmint, Russian sage, Feather reed grass, Stonecrop and Lavender.

Wildlife: Flowers provide nectar and pollen, and birds eat the berries and disperse the seeds. Dense thickets can displace native vegetation; in parts of eastern North America they also create conditions favourable to ticks.

• Root rot in waterlogged soil: improve drainage or move the shrub; do not keep watering saturated ground.
• Powdery mildew: thin crowded growth for airflow, avoid excessive nitrogen feeding and remove badly affected shoots.
• Aphids on soft shoots: dislodge with water and encourage natural predators; use insecticidal soap only if necessary.
• Leaf scorch, especially on yellow-leaved cultivars: provide afternoon shade in hot climates and prevent severe drought during establishment.

Not generally considered poisonous to cats, dogs or horses. Roots, bark and leaves contain alkaloids and should not be eaten by people; ingestion may cause digestive upset. The berries are not generally considered poisonous, but are not recommended as garden food. Thorns can cause puncture wounds to people and animals.

Where it spreads. Invasive across much of the northeastern and midwestern United States, with spread into the Mid-Atlantic and parts of the Southeast; also invasive in parts of southern Canada, including Ontario and Quebec. Birds carry seeds into woodland, where dense stands suppress native plants. Sale or planting is restricted in several US states; check current local rules.

• Common barberry (Berberis vulgaris)

  Usually has finely toothed leaf margins, three-branched spines and longer hanging flower clusters; Japanese barberry has smooth leaf margins, mostly single spines and small flower clusters.

• Ottawa barberry (Berberis × ottawensis)

  This hybrid is often larger, with larger leaves that may have toothed margins and more conspicuous flower clusters; identification can be difficult without close examination.

• Wintergreen barberry (Berberis julianae)

  Has evergreen, leathery, sharply toothed leaves and strong three-branched spines, rather than small deciduous leaves with smooth margins.

The common name refers to its Japanese origin, while thunbergii honours the Swedish botanist Carl Peter Thunberg.

Propagation. Semi-ripe cuttings in summer retain cultivar characteristics; seedlings do not reliably come true. Do not propagate where invasive or restricted, and remove unwanted seedlings promptly.

Accepted botanical name

Berberis thunbergii

In the US and Canada

Introduced in Canada and the lower 48 states.

Native range

Japan.

Measured

Soil pH 5.5 to 7.2. Average height 145 cm.

Sources: GBIF (CC BY 4.0), USDA PLANTS and Trefle (CC BY 4.0). The care and design notes are LandscapeGPT's own.