Leaves of New Zealand Flax (Phormium tenax)
Leaves of New Zealand Flax (Phormium tenax)

New Zealand Flax (Phormium tenax) - Description & Uses

The New Zealand Flax (Phormium tenax) is one of the most attractive architectural plants for ornamental use.

Actually not so exactly the same, but the multitude of very aesthetically interesting varieties, with their green, red or variegated large sword-like leaves, and different sizes.

But exactly the same is an excellent quality fibrous plant, which has enjoyed great glory as a commercial crop, from the beginning of the 20th century and for about three decades.

However, in the following article, emphasis is given mainly to its ornamental side – for the other, the editorial team of "Kalliergeia" reserves.

On the contrary, the above-mentioned team is not reserved, and soon promises a special tribute to the many varieties of the plant – OK not all but the most unique and popular of them.

Phormium tenax is one of the two species that consist the genus Phormium – the other is Phormium colensoi (syn. Phormium cookianum).

And perhaps it is this smaller than small number of species of the genus that gave the opportunity to the systematics of Botany to classify the genus according to the phases of the moon: from the family Liliaceae to the family Agavaceae and from the family Phormiaceae to the family Hemerocalllidaceae.

The editorial team of "Kalliergeia", being in an obvious impossibility of selection, drew a lot, from which the Agavaceae family emerged.

Let the reader regard this taxonomic daring as a (team) teen-age craze that will one day be a thing of the past.

The New Zealand Flax can grow without problems in extremely difficult environments, such as those in seaside areas.

Phormium tenax Plant in a New Zealand's Coastal Area
Phormium tenax Plant in a New Zealand's Coastal Area
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New Zealand Flax - Origin

Phormium tenax (New Zealand Flax) - Map of Origin
Phormium tenax (New Zealand Flax) - Map of Origin

New Zealand Flax (Phormium tenax) – Description & Uses

New Zealand Flax (Phormium tenax) - Brief Description

Family: Agavaceae (Century-Plant Family)

Genus: Phormium

Scientific Name: Phormium tenax J.R.Forst.. & G.Forst.

Common Names: Coastal Flax, Common Flax Lily, Flax, Flax Bush, Harakeke (in Māori), New Zealand Flax, New Zealand Hemp

General Characteristics

Leaf Persistence



Rhizomatous Herbaceous



Growth Rate

Medium to Fast

Flowering Period (Northern Hemisphere)

June – August

Fruiting Period

September – October


2.5-4 m (8-3 ft)


1.5-2.5 m (5-8 ft)

Shapes and Colours

Leaves Shape

Oblong Lanceolate

Foliage Colour


Autumn Foliage Colour


Flowers Shape


Flowers Colour

Yellow, Red




Soil Type: Well-drained, sand, loam

Exposure: Sun, Half-Shade

Soil pH: 4.5-8

Watering: Low

Hardiness: −12 °C (10.4 °F – USDA Hardiness zone 8a)


Specimen, urban planting, parks, garden, pots and containers indoor and outdoor, coastal planting

New Zealand Flax (Phormium tenax) – Description & Uses

Flowering Phormium tenax (Harakeke) in Nature of New Zealand
Flowering Phormium tenax (Harakeke) in Nature of New Zealand

New Zealand Flax (Phormium tenax) - Etymology

Etymology of the Genus Name

The name of the genus Phormium is the Eclatinized version of the Ancient Greek word φορμός (phormos), which means basket woven from fibers. The word φορμός, in turn, comes from the also Ancient Greek φέρω (phérō), which is interpreted as I bring, bear, carry. The etymological sequence of φέρω passes through the Proto-Hellenic *pʰérō, and reaches the Proto-Indo-European thematic root verb *bʰéreti, whose root is *bʰer-. The meaning of the root *bʰer- is to bear, carry. In this way it is rendered aptly, the basic property of the leaves of the genus species, which after processing are converted into fibers used for the construction of various objects – such as baskets, etc.

Etymology of the Species Name

The name of the species tenax is an adjective of Latin origin, which means holding fast, tenacious. It consists of the verb teneō, which means I hold, grasp and the suffix *-āks. The verb tenax comes from the Proto-Italic word *tenēō, and this from the Proto-Indo-European root *ten- which is interpreted as to stretch, draw. The also Proto-Italic suffix *-āks extends the meaning of the verb by expressing a tendency or inclination, and comes from the Proto-Indo-European suffix -āx. And the name of the species tenax is extremely successful, since the fibers from the leaves of the plant species are very strong and contribute to the creation of particularly durable objects.

New Zealand Flax (Phormium tenax) – Description & Uses

New Zealand Flax (Phormium tenax) - Origin & Life Span


The origins of Phormium tenax include New Zealand and Norfolk Island. However, for the island of Norfolk – the birthplace of the Norfolk Island Pine (Araucaria heterophylla) – raises well-founded doubt, as it seems likely to have been moved there by the Maori in the 12th to 14th CE centuries.

Ecology - Habitat

In New Zealand Phormium tenax is found at an altitude that starts almost from sea level and reaches up to the mountain forests, at 1200 to 1300 m, and in a variety of environments such as:

  • Coastal areas – cliffy, rocky or sandy
  • Estuaries and along riversides
  • Permanent or seasonal wetlands – swampy areas or flooded soils

Its population growth takes place on a wide range of substrates, but is favored in peaty and mineral-rich alluvial soils.

The mean annual temperature of its natural habitats is between 8 and 19 °C (46-66 °F), the mean maximum temperature of hottest month is between 11 and 22 °C (52-71 °F), while the mean minimum temperature of coldest month is between 3 and 16 °C (37-61 °F).

As for the mean annual rainfall, this is between 508 and 4330 mm.


The New Zealand Flax, without belonging to the most dangerous invasive plants, has been characterized as invasive in various countries. To make this happen, Homo economicus dip into the plant, by the creation of plantations with Phormium tenax outside New Zealand, in the "golden" era of the plant, when its commercial cultivation for the production of fibers (as we will show below), brought measurable profits.

In this respect, significant problems have arisen in sensitive ecosystems, such as those on small islands.

Among those affected are the South Atlantic islands of St Helena and Tristan da Cunha, the North Atlantic islands Azores, and the Juan Fernαndez Islands of Chile, and the island of Molokai in Hawaii, in the Pacific.

In addition, P. tenax has also been reported as a weed in parts of South Africa and mainland Australia.

Life Span

No one of the plant-lovers has the right to complain about the longevity of Phormium tenax, as this tends to infinity (∞). The immortal side of the New Zealand Flax does not touch metaphysical spheres but is based on the ability of the underground plant’s stem to expand (and reproduce vegetative) through its rhizome. In fact, when a fan of the plant blooms and dies, new clusters of leaves will have formed around the base of the old flowering shoot.

New Zealand Flax (Phormium tenax) – Description & Uses

New Zealand Flax (Phormium tenax) - Landscape Attributes

The New Zealand Flax is a perennial, rhizomatous plant, medium to large in size, with medium to fast growth rate. In its natural habitats it can reach a height of 4 m (13 ft) – sometimes 5 to 6 m (16-20 ft) along with its flowering shoots -, but in cultivation and used as an ornamental it will rarely exceed the height of 2.50 m (8 ft).

It is a predominantly architectural plant, which has vase shape, consisting of clusters (ramets or ofshoots) of long striking leaves. The leaves are mostly green in color (the varieties have leaves of different colors), the upper 1/3 to 1/2 of which often appears curved.

It has a strong root system, rather dense canopy with an irregular outline, and is coarse in texture.

New Zealand Flax (Phormium tenax) – Description & Uses

Abundant Fruits of Phormium tenax
Abundant Fruits of Phormium tenax

New Zealand Flax (Phormium tenax) - Botanical Description


The root system of Phormium tenax consists of fleshy and creeping (or extending in every soil subsurface direction) orange rhizomes, about 5 cm (2 in) in diameter, which are strongly branched, forming a dense network of white fine roots.

Most of them are located in the upper soil layers, at a width of 1.50 m (5 ft) from the center of the plant and at a depth of 50 cm (20 in). However, the total area of the root system reaches as wide and deep as the height of the plant, ie 2.50 m (8 ft) or more.


The leaves are large, with a length ranging between 0.90 and 4.20 m (3-14 ft), while their width ranges between 5 and 12 cm (2-4.5 in). They have an elongated lanceolate shape and a green – bluish green color.

They emerge from the rhizome, are distichous (located in opposite rows), smooth, thick, with entire margins, have strong bast fibers, and on their lower surfaces the midrib characteristically discerns.

They form clusters on every offshoot consisting of 8 to 30 leaves, of which the young grow from the center of the offshoots, while the older leaves on the outside die.

Although the upper 1/2 or 1/3 of the leaves often curved outwards, many leaves remain errect. Such a structure serves, among other things, to avoid the direct effect of the sun’s rays, resulting in significant water savings.

Thus it is possible for them to grow and develop in extremely dry places, such as those of rocky areas and sand dunes.

Flower Stalk

The flowering stem is strong and distinct for a long time, usually reaching a height of about 5 m (16 ft), with a diameter of 2 to 3 cm (0.7-1.2 in). It grows from the center of the plant, is erect, strongly branched, cylindrical in cross section and hairless. Initially it has a fleshy to woody texture and a bluish green color, which when dried changes to gray or black, while it becomes extremely light.


The flowers are placed on a panicle inflorescence, and number 500 to 700. They are hermaphrodite and protandrous – that is, the pollen is mature but the stigma has not yet become receptive for pollination.

They have a tubular shape, and the color is primarily gray-red, but pink or yellow flowers are also found. Their length varies between 2.50 and 5.00 cm (1.2-2.4 in), while they are carried on a peduncle 8 to 10 mm (0.3-0.4 in) long.

They consist of 6 tepals, with the insides being slightly longer, and having slightly convex tips.

Longer than the tepals are the 6 stamens, which emerge from the base of perianth. They have thin filaments, smooth and visibly flattened, on which the linear to elongated anthers are placed.

The 3-locular ovary is superior, with numerous ovules, the style is filiform and the stigma of the pistil small and narrow.

Phormium tenax takes 6 to 8 years to start flowering.


The flowers produce an abundant amount of waxy and powdery light pollen, orange in color, along with more than enough nectar.

Nectar attracts nectar-feeding birds, which by covering their nutritional needs contribute greatly to the pollination of Phormium tenax, carrying pollen with their feathers, from flower to flower.

These nectar-feeding birds include the species:

  • Tūī (Prosthemadera novaeseelandiae)
  • Korimako (Anthornis melanura)
  • Hihi (Notiomystis cincta)
  • Kākā (Nestor meridionalis)
  • Tauhou (Zosterops lateralis)
  • Manu Pango (Turdus merula)

However, apart from the birds, insects (bees, etc.), water and wind also participate in the pollination of P. tenax.

Fruit & Seeds

The fruit is a loculicidally 3-valved capsule, initially fleshy and then woody in texture. Remains for a long time in the plant, having first greenish-red color which at full maturity turns brown – black or black.

It is triangular in cross section, erect, except for its top part, which shows at the apex an abruptly contract. Its length varies between 5 and 10 cm (2-4 in), and contains from 60 to 150 seeds.

The shape of the seeds is flattened – ellipoid, more or less twisted, and their color is polished black. Their size in terms of length varies between 9 and 10 mm (0.35-0.40 in), while in terms of diameter between 4 and 5 mm (0.15-0.20 in).

New Zealand Flax (Phormium tenax) – Description & Uses

New Zealand Flax (Phormium tenax) - Climate and Soil

The New Zealand Flax grows in a wide range of climates and in various soil environments. In relation to the climatic types the following are mentioned:

  • Cf – Warm temperate climate, wet all year
  • Cs – Warm temperate climate with dry summer

(Köppen-Geiger Climate Classification System)


The Phormium tenax adapts to a very wide temperature range, extending the possibility of its ornamental cultivation, beyond its natural ecosystem.

The minimum tolerable temperatures range from -9.5 to -12 °C (15-10.4 °F), which the plant can withstand without significant damage.

With high and very high temperatures it does not face the slightest problem, as it withstands exposure even to those that reach or exceed 40 °C (104 °F).

Soil and pH

The New Zealand Flax grows in a variety of soil types, such as those of light and medium texture, but it is recommended to avoid planting it in heavy clay soils that are permanently waterlogged.

The cultivation of the plant, on the other hand, is favored by the loamy soils that are fertile, rich in organic matter and show excellent drainage.

Here, however, it is worth noting its great tolerance to periodically flooded soils, and even with water with a high salt content.

In terms of soil reaction, soil pH, Phormium tenax adapts to a very wide range of values ranging from 4.5 to 8. But the optimal range for its growth is between 5.5 and 6.5, ie it is in acidic or slightly acidic soils.


The plant can be grown both in sunny and slightly shaded places. Still, it has great tolerance in relatively wind-affected areas, although for its perfect appearance, it is preferable to plant it in relatively protected areas. Finally, the plant is entirely suitable for coastal cultivation and seaside gardens.

New Zealand Flax (Phormium tenax) - Pests & Diseases

The Phormium tenax does not have insurmountable problems with plant parasites grown as an ornamental plant. It will rarely be attacked by pets and will rarely be affected by diseases. However, as a fibrous plant, cultivated on a commercial scale, it was striked the heaviest blow as early as the 1920s, due to the appearance of the disease Flax Dieback (Phormium Yellow Leaf – PYL), which is owing to the phytoplasma (bacterium) Candidatus Phytopensema australiense. The disease was first described in 1908, and is manifested by yellowing and falling of leaves, delayed growth and collapse of the root system, and has as a real possibility the death of the plant. It is transmitted by the Hemiptera sucking insect Oliarus atkinsoni (syn. Zeoliarus atkinsoni), which is treated with systematic insecticide sprays, while for the phytoplasma itself Ca. Phytopensema australiense there are no remedies.


Immediately below are recorded the most important pests of P. tenax.

Various Insects
  • Orthoclydon praefectata (Flax Looper Moth)
  • Tmeolphota steropastis (Flax Notcher Moth)
  • Poliapsis spp.
  • Pseudaulacapsis spp.
  • Balanococcus diminutus (Flax Mealy Bug)

By the use of appropriate insecticides their treatment is effective. 


After the pests, the recording of the diseases follows.

  • Cladosporium spp.
  • Rhizopus stolonifer (Black Bread Mold)
  • Periconiella phormii
  • Glomerella phacidiomorpha
  • Kirramyces phormii

By using the appropriate fungicides the treatment is satisfactory.

New Zealand Flax (Phormium tenax) – Description & Uses

New Zealand Flax (Phormium tenax) - Toxicity & Allergenicity


The leaves of the plant contain the extremely bitter-tasting substances cucurbitacins. Cucurbitacins number about seventeen chemical compounds, are poisonous to some animals, and can cause damage to human organs due to their toxic effects.


There is no indications or evidence that the plant can cause allergic reactions.

New Zealand Flax (Phormium tenax) – Description & Uses

New Zealand Flax (Phormium tenax) - Ecology & Environment

The Phormium tenax plays an important role as a food source, shelter and / or habitat for parts of the fauna in its natural niches. In addition, its contribution to environmental improvement is particularly important.

Food Source

The abundant nectar production during the flowering period feeds not only the birds or the insects involved in its pollination, but also some reptiles – species of lizards belonging to the Infraorder Gekkota – as well as various species of bats. Its seeds are consumed by the duck species Anas superciliosa (Pacific Black Duck).

Habitat for Fauna

The natural populations of the plant in coastal areas provide habitat for the endangered endemic species Megadyptes antipodes, the Yellow-Eyed Penguin.

Environmental Improvement

The New Zealand Flax is also used in various restoration projects, such as those involving:

  • The regeneration of forests
  • Corrosion control
  • The stabilization of the sand dunes
  • Improving landscapes
  • Revegetation, as it is one of the few plants in New Zealand that recovers after fires

New Zealand Flax (Phormium tenax) – Description & Uses

New Zealand Flax Plant in a Garden
New Zealand Flax Plant in a Garden

New Zealand Flax (Phormium tenax) - Use

The Phormium tenax was used in the past and is still used today in various ways. Planetically it has become extremely widespread through its ornamental varieties, while in New Zealand – where it continues to be commercially cultivated as a fibrous plant, albeit on a small scale – it remains closely intertwined with the Maori cultural tradition.

Industrial & Craft Use

The plant has been the subject of systematic commercial cultivation in New Zealand since the early 18th century CE – with the arrival of the first European settlers.

The fibers extracted from the plant were exported all over the world, supplying raw materials mainly to the textile, cord and bag manufacturing industries.

The cultivation of the plant on a commercial scale expanded in the 20th century CE to various countries. In South America, Phormium tenax plantations have been established in Argentina, Chile and Brazil. On the African continent the plant was cultivated in South Africa and Kenya, and in the rest of the world plantings were carried out in Japan, Australia, as well as on the islands of the Azores and St. Helena.

Unfortunately, the inability to find an industrial method of fiber extraction that would improve the mechanical flax stripper of the 1860s and ensure the high quality of hand-dressed fibre, while lowering the cost of the product, gradually led the commercial crop to decline.

However, the fact of the local use of P. tenax fibers on a craft and handicraft scale remains promising, with remarkably upward trends in demand.

Fabrics, carpets, mats, paper as well as various handicrafts are currently produced from the stripped plant fibers.


The ethnobotanical use of P. tenax by Maori communities goes far back in time. And over the centuries, New Zealand’s indigenous people have been able to use the entire plant for practical, nutritional, and therapeutic purposes.

Practical Use

From the leaves and the extracted fibers, the Maori made and still make many objects, decorative but also of everyday use. These include cordages, sandals, mats, baskets, nets, and clothing. The latter even includes the traditional Maori costume, the piupiu swinging skirt, which is worn at cultural ceremonies, dances or important events.

Nutritional Use

The nectar of the flowers is collected and used as a sweetener.

Therapeutic Use

Traditionally, parts and substances of the plant have been used by the Maori to fight and treat various ailments.

Rhizome decoctions were given as anthelmintics, laxatives, as well as for the treatment of stomach disorders, while in the form of pulp the rhizome was spread as a poultice on areas of the body that showed irritation or inflammation.

The gum-like exudate of the leaf base was used as an antiseptic for wounds and burns or applied to areas of the body with rheumatic or sciatic problems, and as a decoction was given to combat diarrhea.

Also, the treated plant fibers were properly shaped and applied as bandages to areas of the body that bore wounds.


Seed oil contains large amounts of linoleic acid, which can replace fish oil, providing an alternative source of omega-3 polyunsaturated fatty acid.

The rhizome contains the anthraquinone substances chrysophanol and emodin, which have a laxative effect, while the antifungal substance musizin is isolated in the roots.

Cucurbitacins have a significant presence in the leaves, which show remarkable antibacterial and anticancer activity.

Use in Garden and Landscape

As an ornamental plant, Phormium tenax with its varieties is utilized by gardening as well as by landscape architecture.

In particular the P. tenax can be used:

  • As a potted plant, in gardens, courtyards and balconies
  • Individually, as a specimen plant
  • Due to its architectural structure, individually, in groups or in mass plantings in gardens of houses and buildings of modern architectural style
  • In coastal areas and in saline soils
  • Combined with other ornamental plants such as the Mediterranean Cypress (Cupressus sempervirens  pyramidalis), the Weeping Lantana (Lantana montevidensis), the Coral Bells (Heuchera "Black Peellarg") and the variegated Geraniums (Pelargonium hortorum)


The References of this Oceanic article that bears again an original title like New Zealand Flax (Phormium tenax) – Description & Uses are presented by the musical ensemble The Harmonic Resonators, with the covered traditional song of Maori E Karanga E Te Iwi E.

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