New Zealand Native Flax

Harakeke (Phormium tenax) and Wharariki (Phormium cookianum)

New Zealand flax, or harakeke, is a hardy perennial plant with striking, sword-shaped leaves. It is a versatile, iconic species used in traditional Māori culture and modern landscaping. Wharariki is its smaller, more delicate relative, often found in coastal and alpine areas.

Characteristics

Phormium tenax (Harakeke)

• Height: Leaves grow 1–3 meters tall, with flower spikes reaching up to 4 meters.
• Leaves: Long, tough, and fibrous; green or bronze with red or yellow margins in some cultivars.
• Flowers: Tall, tubular red or yellow flowers on stalks in summer, rich in nectar.
• Habitat: Found in wetlands, coastal areas, and forests.

Phormium cookianum (Wharariki)

• Height: Leaves grow up to 1.5 meters, with flower spikes up to 2 meters.
• Leaves: Softer and more flexible than harakeke.
• Flowers: Yellow-green flowers that hang downward.
• Habitat: Prefers drier, coastal, and rocky environments.

Propagation

Native flax can be propagated by division or seeds.

1. Division (Preferred Method)

• Timing: Late autumn to early spring (Southern Hemisphere: March–September).
• Process:
  1. Select a mature plant with multiple clumps (fans).
  2. Dig around the base of the plant to expose roots.
  3. Separate fans, ensuring each has roots attached.
  4. Trim leaves back by half to reduce water loss.
  5. Replant immediately in prepared soil or pots.
• Benefits: Produces faster results with identical traits to the parent plant.

2. Seeds

• Timing: Collect seeds in late summer (February–April).
• Process:
  1. Harvest seed pods when brown and dry.
  2. Extract seeds and soak them in water for 24 hours.
  3. Sow seeds in a seed-raising mix, lightly covering with soil.
  4. Keep moist in a warm, shaded area. Germination occurs in 4–8 weeks.
• Benefits: Preserves genetic diversity, but plants take longer to mature.

Cultivation

1. Site Selection

• Sunlight: Prefers full sun but tolerates partial shade.
• Soil: Thrives in well-drained to damp soils. It tolerates poor, sandy, or clay soils.
• Climate: Hardy and tolerant of wind, salt, and frost.

2. Planting

• Spacing: Space plants 1–2 meters apart, depending on the species and intended use.
• Hole Preparation: Dig a hole twice the width of the root ball and as deep as the roots.

3. Watering

• Keep soil moist during the establishment phase (6–12 months).
• Once established, native flax is drought-tolerant but appreciates occasional watering in extended dry periods.

4. Fertilization

• Generally low-maintenance. Compost or a slow-release fertilizer can be added in early spring for faster growth.

5. Pruning and Maintenance

• Remove Dead Leaves: Regularly trim old or damaged leaves close to the base.
• Flower Stalks: Cut back spent flower spikes to tidy the plant.
• Harvesting for Use: Follow Māori tikanga by cutting outer leaves only and avoiding the central rito shoot.

Pests and Diseases

• Generally pest-resistant, though occasional infestations of scale insects or aphids may occur.
• Root rot can develop in overly waterlogged soils. Ensure good drainage to avoid this.

Benefits of Growing Native Flax

1. Wildlife Habitat: Provides nectar for birds (e.g., tūī, bellbirds) and habitat for insects.
2. Erosion Control: Strong roots stabilize soil.
3. Low Maintenance: Drought-tolerant and hardy once established.
4. Cultural Value: Supports traditional weaving and crafting practices.