In recent months I’ve been fortunate to attend two Hui (gatherings), involving researchers, industry and iwi representatives, focussed on two important native plants here in Aotearoa New Zealand, Mānuka (Leptospermum scoparium) & Kānuka (Kunzea ericoides).

Mānuka Hui

In June a two day Bioeconomy Science Institute (BSI) Maiangi Taiao Mānuka Hui attended by around 50 people was held at the Plant and Food (now Bioscience Research Institute) premises in Palmerston North. This was an inspiring event which brought together representatives of Māori groups and industry, with researchers from across all four of the previous Crown Research Institutes (CRI’s) and Callaghan Innovation, now combined into the new Bioeconomy Science Institute (BSI, or Maiangi Taiao. A handful of us had also taken part also in two previous hui on ‘Manuka and More’, held in 2016 in Ruatoria and Te Araroa on the east coast of New Zealand’s north island (Tairawhiti), which I wrote about at the time⁽¹⁾. 

Over the two day meeting, there were around 20 short presentations by researchers, industry and iwi representatives on some of the work done in recent years, involving our treasured native plant, Leptospermum scoparium (Mānuka).  It’s impossible to adequately summarise these presentations here, but quite a range of research projects have taken place or started within the past nine years. Much of this involves Mānuka Honey, given how important this industry  is now to many regions of Aotearoa, and how it was the first to put Mānuka on the global map⁽²⁾.

Kānuka and Mānuka are the dominant native woody species forming early-successional vegetation on formerly forested sites in lowland New Zealand. Their importance as pioneer species has been shown by studies showing that species richness or subsequent biodiversity, was much better in areas where Kānuka and Mānuka were the initial prevalent species⁽³⁾. A collaboration between Comvita and scientists from the Bioeconomy Science Institute has also demonstrated that planting Mānuka forests on former high-country marginal grazing land can significantly restore biodiversity in as little as five years⁽⁴⁾.

The Mānuka honey industry went through a lengthy period of rapid growth in demand and hive numbers over several years prior to 2019. This became unsustainable however, and a range of factors lead to challenging times since then, with registered hive numbers falling sharply from a peak of 918,000 in 2019 to less than 490,000 in 2026. When I wrote about the 2016 Hui, hive numbers were around 350,000⁽¹⁾.

A great deal of evidence however, now suggests much rosier times lie ahead for the Mānuka honey industry. I’ve researched and written four review articles on the science behind this honey over the past 20 months, and the sheer volume and diversity of compelling research findings supporting its many health promoting and medicinal applications, is very encouraging^{(2, 5, 6, 7)}.

Jackie Evans and John Oliver from Comvita discussed work their company has been doing on the compound lepteridine, found only in Mānuka honey, recently shown to inhibit enzymes involved in gastrointestinal inflammation⁽⁸⁾. A clinical trial involving lepteridine-standardized mānuka honey for the treatment of functional dyspepsia, is currently underway⁽⁹⁾.

My talk was entitled “Mānuka – from Plant to Product”, and I spoke about my experience since 1998 with formulating and developing various herbal medicines for internal and topical use containing Mānuka honey, Mānuka oil, dried foliage, and hydroethanolic extracts. In this I incorporated some key issues to consider, when wanting to successfully develop and commercialise health products made using native plants.

Many other interesting presentations were made, including ongoing work into characterising the different genotypes within Mānuka, and methods to ensure better authenticity of Mānuka honey, and to distinguish it from Australian Leptospermum species. The need to preserve and protect mātauranga Māori (traditional Māori knowledge) and taonga species such as Mānuka through placing high value on the interweaving of relationships between people, places and the environment, was also a prominent theme throughout the hui.

A presentation by Grant Smith from the BSI was rather sobering though, as he discussed the continued advance of myrtle rust as a devastating pathogen on several of our other native Myrtaceae species such as ramarama and swamp maire. While others such as Mānuka, Kānuka, Pōhutukawa and rātā have yet to be seriously impacted, the damage this pathogenic fungus has caused to many native bush stands in parts of Australia, and increasing influence of extreme weather events and global warming, suggests a growing threat also to some of our iconic indigenous species⁽¹⁰⁾. The work being done here on identifying mechanisms and genes associated with resistant varieties, may also help our Australian neighbours to better manage their own myrtle rust outbreaks.

At the start of the hui, David Chagne, Jenny Green and Nico Bordes gave an overview of the newly established BSI. Bringing the former CRI’s together again into a combined entity as the primary government agency involved in scientific and industrial research aimed at supporting the growth and resilience of the bioeconomy of New Zealand, makes absolute sense in my view.

Launch of the Bioeconomy Science Institute

Establishment and development of the Biodiscovery Platform, a $42 million government investment to support the development of high-value products and innovation over the next 7 years, was also discussed. This identified the shared sectors direction to build impactful fundable pathways, incorporating a fit for purpose, Treaty-based approach⁽¹¹⁾. The Biodiscovery Platform is in the process of setting priorities and exploring possible research partnerships. A key objective as a sector enabler is to invest in activities that bring groups together, and to establish clear, repeatable pathways for research into our native plants and their bioactivities and possible commercialisation pathways.

Kānuka Hui

A couple of months later in August, an inaugural hui dedicated to Kānuka (Kunzea ericoides), another highly endemic native species to Aotearoa, was put on by the Kānuka Charitable Trust (KCT), with support from the BSI. The Kānuka Charitable Trust was established in 2023 by a group of Māori landowners and business leaders to protect Kānuka as a taonga species and ensure Māori values guide the development of an emerging Kānuka industry, with Manu Caddie and Richard Manning as founding directors⁽¹²⁾.

The hui was facilitated mostly by Nikki Harcourt and Manu Caddie, and attended by landowners, growers, essential oil producers, scientists and researchers and a range of people working with kanuka in their various companies and industries. While as with Mānuka these have to date been based almost entirely on essential oil and honey production, potential applications for other types of products or uses of this botanically related native tree, were discussed.

While ten years ago very little attention was given to Kānuka, it is an important species in forest regeneration. It has been widely planted on erosion-prone land, supports carbon sequestration, encourages biodiversity in flora and fauna, and contributes to rural employment.

Like its botanically related cousin Mānuka, it also possesses many medicinal properties. Traditional applications include for wounds and inflammatory skin conditions, and for several conditions affecting the digestive tract⁽¹³⁾. 

Research within the last few years has shown antibacterial and antifungal activities for Kānuka oil against a range of organisms, including Propionibacterium acnes, and MRSA⁽¹⁴⁾.  Its chemistry and relative bioactivities are variable depending on the location, season and extraction methods, but α-pinene is generally the most abundant compound.

Favourable results were reported from a 2022 clinical trial involving application of a 3% kānuka oil cream for eczema, funded by Hikurangi Bioactives, Honeylab and Callaghan Innovation⁽¹⁵⁾. However, challenges have been encountered with commercialising this product in export markets, including unanticipated regulatory barriers in relation to being able to make therapeutic claims.

Authenticity work

Given some of the mistakes made by the Mānuka honey industry in the past, efforts to establish product authenticity are vital for the future Kānuka industry, in order to ensure product is true to label and to protect its market value and supplier reputation.

Much good work has been done and is underway in this area, particularly that by Nigel Perry from Plant & Food Research, on the phytochemistry and potential markers in Kānuka oil⁽¹⁶⁾. David Speed from ALS Analytica, summarised ongoing studies into identification and characterisation of novel constituents of Kānuka, and distinguishing this from Australian Kunzea species. The monoterpene compound α-pinene is generally most prevalent in Kānuka oil, rather than the β-triketones characteristic of good quality Mānuka oil.

A talk by Sri Govindaraju of PAQ Laboratories, which provides specialist testing techniques to support the local honey industry, described how they have developed an assay method for Kānuka honey, and definitions for multifloral or monofloral honey. Currently a lot of blending of different honey suppliers is occurring, with the true volume of Kānuka honey being produced, is not being captured. The last two years had also seen low yields for Kānuka honey supplies, due to heavy rainfall during the short harvest season.

Kānuka honey was found to contain relatively high amounts of type-2 arabinogalactan proteins, which may contribute to immunostimulant and immunomodulatory properties⁽¹⁷⁾.

Being able to further utilise natural waste products or normally discarded plant parts after harvest or extraction of their most desirable components, and fostering a more sustainable and circular economy, makes absolute sense in the world we live in today.  During extraction of the essential oil of Kānuka, large volumes of hydrosols, or aqueous preparations infused with mostly water soluble plant compounds, are produced. These also have many potential applications in human and animal health. Christel Brunschwig from the BSI discussed research into valorising the spent brush not only into hydrosols, but also as a potential biofuel source or feedstock for other types of processing or production operations.

Karl Fraser and Melissa Savage discussed work they are doing on environmental influences on Kānuka oil production, and an ecologist Meg Gray summarised the impact of cyclones, goats and deer grazing, and water quality, on the quality of a Kānuka forest. Pest control is now recognised as being crucial to avoid forest stagnation and loss of biodiversity, as well as the ability of a Kānuka forest to capture carbon.

Lessons learnt

I spoke about some of the lessons learnt from the Mānuka industry to date, and from my previous NHP industry experiences, including the hurdles and steps required to obtain product licences in Australia, and the importance of having a product development and commercialisation strategy that was fit for purpose. My talk also mentioned the importance of understanding regulatory requirements, as all too often these are not well considered, prior to investment in research and product commercialisation.

Another key message we heard at the hui, was that while stories concerning Kaupapa Māori and traditional knowledge are compelling and can support a global marketing strategy for products made from native plants, these need to be supported by collectivism, and consistency. Given the struggle that native plant based industries and companies in Aotearoa have had to date with attaining good and ongoing growth, yet beckoning and growing market opportunities in many overseas markets, this warrants much more consideration by some elements within the broader sector. In order to succeed with the sustainable, ethical and quality based commercialisation of natural health products manufactured using these indigenous plants, it is critical that producers of Mānuka and Kānuka work collectively to develop and support industry standards, certification, and consistent and adequately resourced research and marketing efforts.

References:

1. Rasmussen PL. Mānuka and More. www.herbblurb.com November 18, 2016.
2. Rasmussen PL. Mānuka and other Honeys – exciting recent research. www.herbblurb.com November 30, 2024.
3. Sullivan Jon J, Williams Peter A, Timmins SM. (2007) Secondary forest succession differs through naturalised gorse and native kānuka near Wellington and Nelson. New Zealand Journal of Ecology 31(1): 22 – 38©New Zealand Ecological Society.
4. https://www.bioeconomyscience.co.nz/news-and-events/news/2026-news/biodiversity-benefits-of-large-scale-manuka-forest-planting
5. Rasmussen PL, Manuka honey as a medicine. New Zealand Doctor, 15 February 2025. ISSN
6. Rasmussen PL. Honey as a medicine: Special properties of mānuka honey. Pharmacy Today, 1 October 2024, published by The Health Media Ltd, Auckland, ISSN 1170-1927.
7. Rasmussen PL. Mānuka honey shows promise in cancer prevention and as treatment adjunct. 1 December 2024, published by The Health Media Ltd, Auckland, ISSN 1170-1927.
8. Lin B, Nair S, Fellner DMJ, Nasef NA et al, The Leptospermum scoparium (Mānuka)-Specific Nectar and Honey Compound 3,6,7-Trimethyllumazine (Lepteridine^TM) That Inhibits Matrix Metalloproteinase 9 (MMP-9) Activity. Foods. 2023 Nov 9;12(22):4072. 
9. Ombasa L, Miller J, Ware L, Abbotts-Holmes H et al, Impact of Mānuka Honey on Symptoms and Quality of Life in Individuals With Functional Dyspepsia: Protocol for a Feasibility Randomized Controlled Trial. JMIR Res Protoc. 2025 May 21;14:e66417.
10. Rasmussen PL. Mānuka and Myrtle Rust. www.herbblurb.com July 19, 2017.
11. https://www.mbie.govt.nz/about/news/government-launches-biodiscovery-platform-to-grow-new-zealands-bioeconomy.
12. https://www.hakanuka.co.nz/
13. Rasmussen PL, Kānuka & Inflammation. Phytomed Medicinal Herbs Ltd, Dec 2022. https://www.phytomed.co.nz/blogs/phytobrief/kanuka-inflammation.
14. Haira TH, Ooi RJ, Pay RA, Paenga B, Caddie M, Skinner D, Harcourt N, Jackson M, Keyzers RA, Munkacsi AB. Antimicrobial-guided metabolomic analysis of essential oil derived from the Aotearoa New Zealand endemic plant Kunzea robusta (Kānuka). Fitoterapia. 2025 Jul;184:106592.
15. Shortt N, Martin A, Kerse K, Shortt G et al, Medical Research Institute of New Zealand’s Pharmacy Research Network. Efficacy of a 3% Kānuka oil cream for the treatment of moderate-to-severe eczema: A single blind randomised vehicle-controlled trial. EClinicalMedicine. 2022 Jul 15;51:101561.
16. Perry N. Kanuka oil: current knowledge and potential markers. Plant & Food Research Dunedin, October 2022