At a glance
Common name: New Zealand flax
Māori name: Harakeke
Botanical name: Phormium tenax
Plant family: Asphodelaceae
Native range: New Zealand and Norfolk Island, under the broad botanical classification
Natural habitat: Coastal areas, wetlands, river margins, open ground and other moist environments
Parts discussed in traditional use: Leaf-base mucilage, roots and fleshy leaf bases
Distinctive constituent: Mucilage containing complex, highly branched polysaccharides
Traditional context: Rongoā Māori, weaving, practical technologies and food use
Modern research: Analysis of mucilage structure, plant carbohydrates and other chemical constituents
Important distinction: Historical medicinal use and laboratory findings do not establish that harakeke is a proven treatment for burns, wounds, digestive complaints or other medical conditions.
Getting to know harakeke
Harakeke is one of the most recognisable native plants in Aotearoa New Zealand. It forms dense fans of long, sword-shaped leaves, which can be dark green, blue-green or glaucous grey-green, depending on the variety and growing conditions.
Mature plants can reach several metres in height. When flowering, they produce tall, sturdy stalks carrying tubular flowers that are often reddish-orange, although other colours occur. These flowers produce nectar that attracts birds, making harakeke an important part of many native and restoration planting schemes.
The plant grows naturally in a range of environments, including coastal slopes, wetlands, estuaries, lake margins and riverbanks. It tolerates a variety of conditions but generally grows well where soil moisture and drainage are suitable.
Its botanical name is Phormium tenax. The word tenax refers to its toughness, an appropriate description of the durable fibres running through its leaves.
Harakeke is sometimes confused with wharariki (Phormium cookianum), often called mountain flax or New Zealand mountain flax. The two species are closely related and can hybridise, but they are botanically distinct. Wharariki generally has more drooping leaves and twisted, pendulous seed capsules, whereas harakeke characteristically has more upright seed capsules.
This distinction matters when discussing traditional knowledge, plant chemistry and product sourcing. Some scientific research examines both species together, and findings for one should not automatically be attributed exclusively to the other.
Harakeke is also not the same plant as common or European flax (Linum usitatissimum), which is cultivated for linen fibre and linseed oil. The plants have different botanical identities, growth forms and uses.
Harakeke as a taonga
Harakeke has long been central to Māori life, providing materials for clothing, mats, baskets, fishing equipment, ropes, bindings and many other practical items.
Its fibres can be processed into muka, the fine fibre used in traditional weaving. Depending on the variety and how the material is prepared, harakeke can provide fibres suited to different purposes, from robust ropes and nets to softer woven garments.
Māori weavers historically cultivated selected varieties in pā harakeke — managed groves or plantations of harakeke. Different varieties were valued for their fibre strength, softness, colour and suitability for particular weaving projects.
The plant also carries cultural significance beyond its practical uses. A commonly taught interpretation likens the fan of a harakeke plant to a whānau, or family. The central young shoot, the rito, represents a child, while the leaves immediately surrounding it, the awhi rito, represent its protectors. The outer leaves are associated with older generations.
This symbolism provides a useful explanation for why traditional harvesting practices emphasise protecting the centre of the plant. If the youngest growth is damaged, the plant's continued growth may be compromised.
Specific tikanga and practices vary among iwi, hapū, whānau and weaving traditions. The symbolism described here is widely recognised, but it should not be taken to mean every community uses precisely the same teachings or harvesting rules.
Harakeke is therefore not simply a raw material or medicinal ingredient. It is a living taonga with ecological, cultural, practical and spiritual significance.
Traditional medicinal uses
Alongside its role in weaving and everyday life, harakeke has a documented history of medicinal use.
Ethnobotanical records compiled by Manaaki Whenua – Landcare Research describe the use of several parts of the plant, including mucilage from the base of the leaves, roots and fleshy leaf bases.
These records include historical accounts from Māori sources as well as observations recorded by early European writers and other historical informants. They provide valuable evidence of past practices, but they do not always preserve the full cultural context, preparation methods or circumstances in which a remedy was used.
Pia harakeke: the leaf-base mucilage
One of harakeke's most distinctive traditional applications involves pia harakeke, the slippery, gel-like mucilage found at the base of the leaves.
Historical accounts describe this material being applied to burns, scalds, wounds and chafed skin. Its soft consistency helps explain why it was valued in topical applications.
Historical literature also records its internal use for diarrhoea and dysentery. These are descriptions of traditional practice, not recommendations to ingest homemade harakeke preparations today.
Roots and fleshy leaf bases
Historical sources also describe the use of harakeke roots and the thick bases of the leaves in remedies for constipation, digestive complaints and other conditions.
Some older accounts characterise root preparations as purgative, meaning they could strongly stimulate bowel evacuation. That is an important safety consideration rather than an endorsement of their use.
The strength and composition of preparations made from roots may vary, and reliable modern dosing and safety information is limited. The existence of historical recipes does not establish that they are suitable for contemporary self-treatment.
Traditional wound care
Historical accounts describe the use of dressed harakeke fibre as a wound dressing, alongside other preparations made from leaf-base mucilage or roots.
These practices reflect the material properties and practical usefulness of the plant, but they should not be confused with modern sterile wound products. A plant preparation collected or made at home may contain microorganisms or other contaminants, and application to serious wounds could delay essential medical care.
Understanding historical records
Historical medicinal records are most useful when interpreted carefully. They can reveal which plant parts were used, the complaints people sought to address and the physical properties that made the plant useful.
They do not necessarily tell us whether a remedy was consistently effective, which dose was appropriate, how frequently adverse effects occurred or how the treatment compared with other options.
Rongoā Māori is also broader than the written historical record. Knowledge and practices continue to be maintained by Māori practitioners and communities, and it would be misleading to reduce this living tradition to a list of isolated remedies.
What is pia harakeke?
Mucilage is a naturally occurring mixture of complex carbohydrates, known as polysaccharides, that absorb and retain water.
When hydrated, these compounds can produce a thick, slippery or gel-like material. Mucilage occurs in a range of plants, including marshmallow (Althaea officinalis), psyllium (Plantago species) and several members of the mallow family.
In harakeke, the mucilage is found around the fused bases of the leaves. It has historically been collected as a soft, viscous material and is sometimes described as a plant gum.
The terms mucilage and gum are often used interchangeably in historical writing, although they can refer to materials with different chemical and physical properties.
The plant's mucilage has two areas of interest:
- Traditional use: its slippery consistency helps explain the history of topical applications and other recorded preparations.
- Material science: its ability to retain water and influence the thickness and flow of liquids makes it interesting as a potential botanical ingredient.
The second point can be investigated experimentally by measuring the material's composition, molecular structure and behaviour under controlled conditions.
However, the physical properties of a gel do not automatically establish a medicinal effect. A substance that coats a surface or forms a thick film has not necessarily been shown to reduce inflammation, prevent infection or accelerate tissue repair.
Those outcomes require evidence from appropriately designed biological and clinical research.
What does harakeke mucilage contain?
Scientific analysis has identified harakeke mucilage as a complex, highly branched polysaccharide material.
Studies of the material extracted from Phormium species describe an acidic xylan containing several types of sugar units, particularly xylose, arabinose and glucuronic acid.
These components form a complex carbohydrate structure known as glucuronoarabinoxylan.
Xylose
Xylose is a simple sugar that forms part of several plant polysaccharides. In harakeke mucilage, xylose is an important component of the main carbohydrate structure.
The arrangement of xylose units and the way they connect with other sugars influence the structure and physical behaviour of the material.
Arabinose
Arabinose is another simple sugar that occurs in plant polysaccharides. It contributes to the branching and overall architecture of the mucilage.
Its relative abundance can vary among samples and varieties of Phormium. This is one reason the chemical composition of harakeke-derived material should not be assumed to be identical across all plants.
Glucuronic acid
Glucuronic acid is a sugar acid found in many biological and plant-derived polysaccharides. Its presence contributes acidic character to harakeke mucilage and affects the chemistry of the resulting polymer.
Molecular size and branching
Harakeke mucilage has been characterised as a high-molecular-weight, highly branched polysaccharide. Its extensive branching contributes to its unusual physical properties in water.
The molecular size of the polysaccharide and the arrangement of the sugar units are important to researchers studying how the material dissolves, holds water and behaves when mixed with other ingredients.
The chemical profile is not necessarily constant. Researchers have reported differences in the proportion of sugar components among Phormium varieties and between harakeke and wharariki. Growing conditions, the material collected and the extraction method may also affect the result.
This variability matters when considering whether harakeke mucilage could be used reliably in a manufactured product.
What does modern research tell us?
Modern research has examined harakeke's chemistry, particularly its mucilage and carbohydrate composition. This work helps explain why the plant produces a viscous material and provides a scientific basis for assessing its potential applications.
However, the research landscape is important to understand: chemical and material studies are not the same as clinical trials testing a herbal remedy in people.
Research into the structure of harakeke mucilage
A study published in 2006 examined acidic xylans exuded from the leaves of Phormium tenax and Phormium cookianum.
The researchers isolated mucilage from the leaf bases and investigated its chemical composition, including the arrangement of its carbohydrate components.
The study supported the identification of harakeke mucilage as a highly branched acidic xylan. It also found differences in its composition between varieties and between the two species examined.
This work helped move the discussion beyond a simple description of the material as plant gum. Its chemistry could be analysed and compared, making it possible to study relationships between molecular structure and physical properties.
It also highlights a key limitation: results from research involving several Phormium varieties cannot necessarily be applied identically to every plant sold under the general name New Zealand flax.
Physical properties and potential formulation uses
The viscosity of harakeke mucilage makes it of interest to researchers and product developers.
In material science, viscosity describes resistance to flow. A viscous liquid moves less readily than a thin liquid, while some polysaccharide solutions change their flow behaviour as force is applied.
Harakeke mucilage has been investigated as a botanical material with potential functional applications, including as a thickener or stabilising ingredient.
Similar plant polysaccharides are used in the development of food, cosmetic and pharmaceutical formulations because they can contribute to texture, water retention and the stability of mixtures.
However, potential usefulness as an ingredient depends on factors such as manufacturing consistency, purity, compatibility with other ingredients, storage stability and suitability for the product's intended purpose.
The fact that a substance can thicken a formulation does not demonstrate that it improves a health outcome.
Research into other harakeke constituents
Research on Phormium tenax has also investigated other chemical constituents, including compounds found in the roots and carbohydrates present in its leaves.
These studies contribute to a wider understanding of the plant's chemistry. Some research has examined biological activity in laboratory assays, but such findings do not establish a safe and effective human dose or confirm that a traditional preparation treats a particular condition.
In addition, research involving an isolated chemical compound cannot automatically be applied to the whole plant. The concentration, extraction process and interactions among constituents can all differ.
Has harakeke been clinically proven to heal wounds or burns?
The traditional use of pia harakeke for burns and wounds is documented in historical sources. Its mucilage chemistry and physical properties have also been investigated scientifically.
However, the research reviewed for this guide does not establish that harakeke preparations are clinically effective treatments for burns, infected wounds or other skin conditions.
Modern wound care requires attention to contamination, tissue damage, infection risk and the severity of the injury. A historical preparation should not be assumed to meet the standards required of a modern wound-care product.
What about digestive complaints?
Historical records describe harakeke preparations being used for diarrhoea, dysentery and constipation. Some root preparations were recorded as purgatives.
These accounts provide historical context, but there is insufficient clinical evidence to recommend harakeke as a treatment for these conditions. In particular, a traditional purgative preparation cannot be assumed to have a predictable or safe effect.
Persistent diarrhoea, blood in the stool, severe abdominal pain and significant dehydration can require medical assessment. A herbal preparation should not delay appropriate care.
The overall picture: Harakeke has a documented medicinal history, and modern research has clarified aspects of its distinctive mucilage chemistry. Its potential as a botanical material is scientifically interesting, but clinical evidence establishing specific medicinal benefits remains insufficient.
Harakeke in contemporary products
Although harakeke is best known for its fibre and cultural significance, its mucilage has also attracted interest in contemporary product development.
Any modern use should be evaluated according to the actual preparation and the purpose for which it is intended.
Topical products
The water-retaining and thickening characteristics of plant mucilage can be useful when formulating creams, gels and other topical products.
A commercially formulated product containing harakeke-derived ingredients should be assessed according to its complete ingredient list, quality controls, intended use and supporting evidence.
The presence of harakeke does not establish that the finished product is proven to treat burns, eczema, infections or wounds. Claims about those benefits require relevant evidence for the product and its formulation.
Cosmetic formulations
Mucilage can be of interest in cosmetics because it may contribute to texture and the feel of a product on the skin.
For cosmetic use, consistency, stability, microbial quality and compatibility with the other ingredients all matter. Plant-derived materials still require appropriate processing and quality controls.
Food and other applications
Harakeke's flowers have historically been valued for their nectar, while the plant's fibres have a long history of practical use.
Its mucilage may also be relevant to research into plant-derived polysaccharides for food and industrial applications. Such possibilities should be distinguished from claims about consuming harakeke as a medicinal remedy.
For consumers, clear product labelling helps establish whether the ingredient is being used for texture, as part of a cosmetic formulation or with a specific medicinal claim.
Growing harakeke at home
Harakeke is a hardy native plant that can be suitable for gardens, shelter planting and ecological restoration.
It commonly grows in moist environments but can tolerate a range of conditions once established. Rich, well-drained soils generally support good growth, while prolonged drought or extended flooding may reduce its performance.
Plants produce dense fans of leaves and can spread into substantial clumps. Before planting, consider the mature size of the variety and the space needed around it.
Harakeke is commonly propagated by dividing established rooted fans or by growing it from fresh seed. Numerous cultivars are available, and some ornamental plants have been selected or hybridised for different leaf colours and growth habits.
For anyone interested in weaving, a dedicated pā harakeke can provide a sustainable source of fibre when plants are cultivated and harvested appropriately.
Recognising plant health problems
Harakeke can be affected by yellow-leaf disease, also known as flax dieback. This condition is associated with a phytoplasma transmitted by the native flax plant hopper. Symptoms can include abnormal yellowing, stunted young leaves and eventual decline of the plant.
A sudden change in the condition of a clump should not automatically be attributed to drought, nutrient deficiency or normal ageing. Where a plant is showing substantial decline, seek appropriate local horticultural advice before trying treatments.
Harvesting with respect and sustainability
Harakeke is a taonga, and responsible harvesting involves more than simply selecting a leaf.
Traditional weaving practices commonly emphasise protecting the centre of the plant. The rito and the leaves immediately surrounding it are left undisturbed, while suitable outer leaves may be harvested. This approach supports continued growth and reflects the widely recognised family symbolism associated with the plant.
Specific practices and tikanga vary among iwi, hapū, whānau and weaving traditions. Anyone learning to harvest harakeke should follow appropriate local guidance rather than assuming that a short online description covers every situation.
From an ecological perspective, harvesting should avoid damaging the plant, weakening the clump or removing more material than it can reasonably replace.
For medicinal or cosmetic research, the part collected should also be recorded accurately. The leaf-base mucilage, roots and leaves are not chemically interchangeable, and samples intended for research require appropriate identification and handling.
When gathering native plant material, establish who owns the land, whether permission is needed and whether any collection restrictions apply. Respect for the plant includes respect for the people, place and knowledge connected with it.
Safety considerations
Harakeke's traditional history is significant, but reliable modern safety information for medicinal preparations is limited. Its safety should not be assumed across every plant part, extraction method or route of use.
Burns and wounds: Do not apply homemade mucilage or unverified plant preparations to serious burns, deep wounds, infected skin or injuries that require medical attention. Home-prepared material is not necessarily sterile, and appropriate wound care may be delayed.
Internal use: Historical records include the use of harakeke root preparations as purgatives. Strong laxative or purgative effects can lead to diarrhoea, fluid loss and other complications. Do not use historical root recipes as a contemporary self-treatment guide.
Pregnancy and breastfeeding: Reliable safety information for medicinal harakeke preparations is insufficient. Avoid medicinal use during pregnancy or breastfeeding without advice from an appropriate health professional.
Children: Do not assume a historical preparation is appropriate for children. Reliable paediatric dosing and safety information is lacking.
Medicines and ongoing health conditions: Information about interactions with modern medicines is limited. If you take regular medication or have an ongoing health condition, discuss a specific harakeke product with a qualified health professional or pharmacist.
Plant identification and contamination: Botanical identity, collection site, processing and storage all matter. Plant material gathered from contaminated areas or processed without suitable hygiene may introduce additional risks.
Persistent symptoms: Do not rely on harakeke for ongoing digestive complaints, unexplained bleeding, severe diarrhoea or other symptoms that warrant medical assessment.
These cautions do not dismiss traditional knowledge. They distinguish historical practices from the evidence and safety standards needed when recommending a preparation for contemporary medicinal use.
Understanding harakeke's potential
Harakeke is an excellent example of how a plant can hold value across many different areas of life.
Its fibres support an extensive tradition of weaving and practical craftsmanship. Its nectar provides a food resource for birds, and its growth habit makes it useful in restoration planting. Its mucilage provides a further area of scientific interest because its polysaccharides have distinctive structures and flow properties.
Traditional accounts describe the use of pia harakeke for burns, wounds and digestive complaints. Modern research has characterised aspects of the mucilage's chemistry, creating a clearer foundation for further investigation.
Those findings are meaningful, but they answer different questions. A record of traditional use describes a practice. Chemical analysis establishes what a material contains. A clinical study is needed to determine whether a particular preparation provides a reliable health benefit in people.
For a practitioner or consumer, recognising those distinctions makes it possible to appreciate harakeke without making claims that the evidence cannot support.
In summary
Harakeke (Phormium tenax), or New Zealand flax, is an indigenous plant of Aotearoa with deep cultural, ecological and practical significance.
Its fibres have long been used for weaving, clothing, ropes, fishing equipment and other essential materials. Historical records also describe the medicinal use of pia harakeke, the mucilage found at the base of its leaves, as well as traditional preparations involving roots and fleshy leaf bases.
Modern research has identified harakeke mucilage as a highly branched polysaccharide containing xylose, arabinose and glucuronic acid. Its physical properties have attracted interest for potential use in botanical formulations and other materials.
However, modern clinical evidence establishing that harakeke treats burns, wounds or digestive complaints remains insufficient. Traditional preparations should not automatically be treated as safe or effective contemporary medicines.
Harakeke is best understood through a combination of botanical knowledge, respect for Māori cultural practice, responsible plant stewardship and careful interpretation of scientific evidence.
Sources and further reading
1. New Zealand Plant Conservation Network. Phormium tenax — botanical identification, distribution, habitat, propagation, ecology and cultural importance. https://www.nzpcn.org.nz/flora/species/phormium-tenax/ 2. Manaaki Whenua – Landcare Research, Ngā Rauropi Whakaoranga. Phormium tenax. Harakeke. Historical ethnobotanical records covering Māori terminology, food, fibre and medicinal uses. https://rauropiwhakaoranga.landcareresearch.co.nz/names/f7dbd5a8-9779-451f-ad75-72f1866c6e1b 3. Te Ara – The Encyclopedia of New Zealand. The art of te whare pora. Traditional Māori weaving, fibre preparation and harvesting practices. https://teara.govt.nz/en/maori-weaving-and-tukutuku-te-raranga-me-te-whatu/page-1 4. Wehi, P. M. et al. (2007). “Biological flora of New Zealand 10. Phormium tenax, harakeke, New Zealand flax.” New Zealand Journal of Botany, 45(4), 521–544. https://doi.org/10.1080/00288250709509737 5. Sims, I. M. and Newman, R. H. (2006). “Structural studies of acidic xylans exuded from leaves of the monocotyledonous plants Phormium tenax and Phormium cookianum.” Carbohydrate Polymers. Research on the structure of harakeke and wharariki mucilage. https://www.sciencedirect.com/science/article/abs/pii/S0144861705004625 6. Polysaccharides from New Zealand Native Plants: A Review of Their Structure, Properties, and Potential Applications (2019). Plants, 8(6), 163. A review of mucilage and other plant polysaccharides from selected native New Zealand species. https://pmc.ncbi.nlm.nih.gov/articles/PMC6630198/ 7. Sims, I. M., Cairns, A. J. and Furneaux, R. H. (2001). “Structure of fructans from excised leaves of New Zealand flax.” Phytochemistry, 57(5), 661–668. https://pubmed.ncbi.nlm.nih.gov/11397431/ This guide is educational and is not a substitute for individual medical advice or guidance from a qualified rongoā Māori practitioner.