New Zealand Flax

Basic Information

Common Name: New Zealand Flax
Scientific Name: Phormium tenax
Native Habitat: New Zealand

History / Discovery / Cultivator

Phormium tenax, commonly known as New Zealand Flax or Harakeke in Māori, holds a significant place in the history and culture of New Zealand. Long before European arrival, the indigenous Māori people utilized this remarkably versatile plant extensively. Harakeke was not merely a plant; it was a vital resource deeply interwoven with their daily lives and spiritual beliefs. Its tough, fibrous leaves were expertly processed using traditional methods like scraping and beating to produce a strong, durable fiber. This fiber was then transformed into an astonishing array of essential items – clothing (like the famous cloaks, _kākahu_), ropes, baskets (_kete_), mats, fishing nets, and even sails. The plant’s resilience and widespread availability made it a cornerstone of Māori technology and society. Different varieties of Harakeke were recognized and cultivated by Māori for specific purposes, depending on the quality and fineness of their fibers.

European explorers first encountered Phormium tenax upon reaching New Zealand. Captain James Cook, during his voyages in the late 18th century, noted the plant and its use by the Māori. Samples were collected and taken back to Europe, sparking interest in its potential as a source of fiber. The plant’s scientific name, Phormium, derives from the Greek word ‘phormos’, meaning ‘basket’, acknowledging its use in weaving. ‘Tenax’ is Latin for ‘tenacious’, referring to the strength of its fibers.

In the 19th century, New Zealand Flax became a valuable export commodity. European settlers established industries dedicated to processing the fiber, though often without the sophisticated knowledge and care applied by the Māori, leading to variable quality. The flax industry fluctuated throughout history, facing challenges from competing fibers like jute and sisal, and changing economic conditions. Despite the decline of large-scale commercial fiber production, the plant’s ornamental qualities began to gain prominence globally.

Cultivation shifted from fiber production to horticulture. Phormium tenax proved to be remarkably adaptable and visually striking. Its architectural form, tall flower stalks, and often colorful foliage (especially in various cultivars like those with bronze, purple, red, or variegated leaves) made it popular in landscaping worldwide, particularly in coastal and Mediterranean climates, but also as a structural element in mixed borders and containers in cooler regions. Numerous cultivars have been developed over the decades, selected for traits like color, leaf width, size (from dwarf varieties to towering specimens), and form, solidifying its place as a widely cultivated ornamental plant. While traditional Māori use and knowledge continue, particularly in cultural contexts, the plant is now most commonly recognized internationally for its dramatic presence in gardens and landscapes.

Plant Care Summary

Botanical Insights

Adaptations

Phormium tenax exhibits several key adaptations that contribute to its hardiness and success in diverse environments. Its most notable feature is its dense cluster of tough, strap-like leaves arising from a robust rhizomatous root system. This root structure provides excellent anchorage and allows the plant to spread vegetatively, forming large clumps that can withstand strong winds, common in its native exposed habitats. The leaves themselves are rigid and fibrous, minimizing water loss through transpiration compared to broad-leaved plants. The plant’s ability to tolerate a range of soil conditions, including poor or boggy soils as well as drier, well-drained ones (provided drainage is adequate), adds to its adaptability. The tall, rigid flower stalks are well-suited to presenting flowers to birds (like tūī and bellbirds in New Zealand), which are its primary pollinators, allowing efficient transfer of pollen.

Propagation Methods

The most common and effective method for propagating Phormium tenax is by division of the rhizomatous clumps. This is typically done in spring or early autumn. Large clumps can be dug up and carefully divided into smaller sections, each containing a portion of the rhizome and a healthy fan of leaves. Any damaged or diseased roots or leaves should be removed. The divisions can then be replanted immediately in suitable locations. Phormium can also be propagated from seed, but this is less common in cultivation, especially for specific cultivars, as seed-grown plants may not come true to the parent plant’s characteristics (like leaf color or size). Seed collected from the capsules ripens in late summer to autumn and can be sown in a well-draining seed mix.

Toxicology

Phormium tenax is generally considered non-toxic or only very mildly toxic to humans and common pets such as cats and dogs. Ingesting parts of the plant is unlikely to cause severe poisoning. However, like many fibrous plants, consuming large quantities may cause minor digestive upset, such as vomiting or diarrhea, due to mechanical irritation or indigestible fiber content. The sap is generally not irritating. If ingestion occurs and symptoms persist or are severe, contacting a veterinarian or poison control center is always recommended, but serious toxic effects from Phormium tenax are not typically reported.

Common Problems

Pests:

• Mealybugs (can sometimes infest the base of leaves in protected locations)
• Spider mites (less common, usually in dry, dusty conditions)
• Scale insects (occasionally found on leaves or stems)

Diseases:

• Root rot (most common issue, caused by poor drainage)
• Leaf spot (fungal diseases, usually exacerbated by wet conditions)

Other:

• Leaf tips browning or splitting: Often caused by underwatering, windburn, or extreme temperatures.
• Yellowing leaves: Can indicate overwatering (leading to root issues), nutrient deficiency, or simply old age of the outer leaves.
• Failure to thrive: Could be due to poor drainage, insufficient light, or very poor soil conditions.

Rarity & Value

Rarity:

The species Phormium tenax itself is very common in its native range and widely cultivated globally, so it is not considered rare. However, specific named cultivars, especially newer introductions or those with highly sought-after characteristics like intense variegation or unique colors, can be less common in nurseries or harder to find, making them relatively rarer within the horticultural trade compared to the standard green form. Truly rare forms would likely be specific, perhaps unstable, mutations or very old, established cultivars with limited propagation.

Value:

The market value of Phormium tenax is primarily influenced by its size, age, and cultivar type. Larger, more mature specimens naturally command higher prices than young plants. The specific cultivar is a major factor; common green varieties (Phormium tenax) or popular bronze ones (Phormium tenax ‘Purpureum’) are generally inexpensive and widely available. Cultivars with vibrant or complex variegation (e.g., ‘Variegatum’, ‘Yellow Wave’, ‘Duet’) or unusual colors (e.g., deep red, pink hues like ‘Pink Stripe’) are typically more expensive due to slower growth, more complex propagation needs, or higher demand in the ornamental market. Rarity of a specific cultivar also plays a role in its value. Provenance (where a plant was grown or its history) is less significant for common Phormium compared to collectible houseplants, but quality of growth and health are always factors.