Phormium cookianum 'Black Adder' · Asphodelaceae

New Zealand Flax

✅ Pet-friendlyPerennial, maintaining foliage year-round.50 to 100 cm

LightFull sun

WaterModerate

DifficultyEasy

ColdWithstands light frosts down to minus 5 degrees Celsius.

Full sunModerateEasyWithstands light frosts down to minus 5 degrees Celsius.

Description & origin

Phormium cookianum 'Black Adder' is a perennial plant with dark burgundy sword-shaped leaves. Ideal for modern gardens, it offers a striking contrast with other plants.

Size

Can reach up to 100 cm in height and width.

Foliage

Evergreen foliage that maintains color year-round.

Flowering

This species does not produce flowers in domestic cultivation.

Detailed care

Light

Prefers full sun for optimal growth.

Soil

Well-drained soil is essential to prevent waterlogging.

Watering

Moderate watering, allowing the soil to dry slightly between waterings.

Temperature

Tolerates light frosts but prefers mild climates.

Fertilising

Fertilize in spring with a balanced fertilizer to promote growth.

Repotting

Transplant in spring or early autumn.

Pruning

Remove dry or damaged leaves to maintain appearance.

Propagation

Propagates by division in spring.

Common problems

Root rot

Occurs in poorly drained soils. Avoid waterlogging.

Yellowing leaves

May indicate overwatering or nutrient deficiency.

Snail damage

Snails can damage leaves. Use baits or natural barriers.

Uses & curiosities

In the garden

Borders
Coastal gardens
Modern gardens

Other uses

Excellent for creating visual contrasts in landscaping.

Did you know…

This plant is native to New Zealand and is known for its resistance to wind and salinity.