Metrosideros carminea
Common names
carmine rātā
Biostatus
Native – Endemic taxon
Category
Vascular
Structural class
Lianes & Related Trailing Plants - Dicotyledons
Simplified description
Woody long-climbing vine. Mature plants only reproductive. Juvenile foliage hairy, with young growth often pinkish. Adult leaves more or less circular, dark glossy green above, pale green below, surfaces without any obvious glandular spotting. Flowers carmine borne in dense, terminal, fluffy, clusters.
Flower colours
Red/Pink
Detailed description
Vine up to 15 m (usually less). Growth dimorphic, juvenile and climbing vines sparingly branched, mature (adult - reproductive state) heavily branched. Bark dark brown to grey, ± tessellated, and flaking in tabular shards. Branchlets terete, finely pubescent. Leaves close-set, coriaceous, petiolate; petioles 1–3 mm. long; lamina of juveniles 10–20 × 8–18 mm, suborbicular, orbicular to broadly ovate, apices obtuse to subacute; adaxially green to dark green, abaxially paler (young foliage (and branchlet growing points) usually pink-tinged), both surfaces finely to distinctly pubescent, hairs pinkish, oil glands conspicuous abaxially not punctate; adult lamina 15–35 × 7–30 mm, elliptic-oblong, ovate-oblong to broad ovate, apices obtuse to subacute, adaxially dark green and glossy, adaxially paler, ± glossy, ± glabrous. Inflorescences in axillary and/or terminal few- to many-flowered cymose botyria crowded toward apex of branchlets (often obscuring the foliage); peduncles and pedicels finely pubescent, peduncles 20–60 mm long, pedicels 5–10 mm long. Hypanthium urceolate or globose, initially fleshy, finely pubescent, ± glabrescent; calyx lobes 1.8–2.3 mm long, oblong, subacute. Petals 5 × 4 mm, caducous, suborbicular, carmine, shortly clawed, margins ± unevenly crenulate to indistinctly toothed or undulose; stamens numerous 10–15 mm long, carmine. Capsule 6–9 mm diameter, subglobose to globose, 3–(4)-valved, exserted, ± woody, dark brown to brown-black when mature.
Similar taxa
Adult vines are easily recognised when flowering by the profusion of carmine flowers - quite unlike any other New Zealand rata vine. However, this species is most often found as juveniles, and these have a superficial resemblance to Metrosideros perforata. From that species M. carminea can be distinguished by the branch tips and young emergent leaves which are very hairy and tinged pink. Both species have prominent oil glands on their leaves but in M. carminea these are never pitted (punctate) like those of M. perforata.
Distribution
Endemic. New Zealand: North Island (from Te Paki south to Taranaki in the west and Mahia Peninsula in the east).
Habitat
Coastal to montane (mainly coastal to lowland). A vine of closed forest and forest margins (often along water ways and on ridge lines, especially on rock outcrops and cliff faces).
Current conservation status
The conservation status of all known New Zealand vascular plant taxa at the rank of species and below were reassessed in 2022-2023 using the New Zealand Threat Classification System (NZTCS) – more information about this can be found on the NZTCS website. This report includes replaces all previous NZTCS lists for vascular plants. Previous assessments can be found here.
- Conservation status of vascular plants in Aotearoa New Zealand, 2023. 2024. Peter J. de Lange, Jane Gosden, Shannel P. Courtney, Alexander J. Fergus, John W. Barkla, Sarah M. Beadel, Paul D. Champion, Rowan Hindmarsh-Walls, Troy Makan and Pascale Michel Department of Conservation. Source: NZTCS and licensed by DOC for reuse under the Creative Commons Attribution 4.0 International licence.
2023 | At Risk – Declining
Threats
Metrosideros carminea is most often found as juveniles, in part because the adult vines (at least in dense forest) are often overlooked as they occur high up in the canopy. In some areas adult vines are heavily browsed by possums.
When myrtle rust (Austropuccinia psidii) was detected in New Zealand (May 2017) the conservation status was upgraded as a precautionary measure to ‘Threatened – Nationally Vulnerable’ because, on best advice, it was believed that no indigenous Myrtaceae had resistance to the myrtle rust disease (de Lange et al. 2018).
Myrtle rust (Austropuccinia psidii) is an invasive fungus that threatens native myrtle species. Learn more myrtlerust.org.nz.
Detailed taxonomy
Genus
Family
Synonyms
Metrosideros diffusa Hook.f.
Endemic taxon
Yes
Endemic genus
No
Endemic family
No
Ecology
Flowering
August–November
Fruiting
January–April
Propagation technique
Easily grown from rooted pieces. Also grown from semi-hardwood cuttings. Indeed adult plants are often propagated from cuttings and while these don’t climb they form an excellent small shrub suitable for rockeries and tub or pot culture. Metrosideros carminea is an excellent vine for growing up walls and rock faces, doing best if its roots are planted in a free draining, humus enriched, moist soil, and the plants allowed to climb up into the sun. Metrosideros carminea is frost sensitive and young vines will need to be carefully nurtured until they are well established.
Other information
Cultivation
Commonly available from most retail nurseries, though often sold as adult cutting grown plants only (these will not climb).
Etymology
metrosideros: Iron heart
carminea: Carmine or red-coloured
Manaaki Whenua Online Interactive Key
NVS code
The National Vegetation Survey (NVS) Databank is a physical archive and electronic databank containing records of over 94,000 vegetation survey plots - including data from over 19,000 permanent plots. NVS maintains a standard set of species code abbreviations that correspond to standard scientific plant names from the Ngä Tipu o Aotearoa - New Zealand Plants database.
METCAR
Chromosome number
2n = 22
Previous conservation statuses
The conservation status of all known New Zealand vascular plant taxa at the rank of species and below were reassessed in 2022-2023 using the New Zealand Threat Classification System (NZTCS) – more information about this can be found on the NZTCS website. This report includes replaces all previous NZTCS lists for vascular plants. Previous assessments can be found here.
- Conservation status of vascular plants in Aotearoa New Zealand, 2023. 2024. Peter J. de Lange, Jane Gosden, Shannel P. Courtney, Alexander J. Fergus, John W. Barkla, Sarah M. Beadel, Paul D. Champion, Rowan Hindmarsh-Walls, Troy Makan and Pascale Michel Department of Conservation. Source: NZTCS and licensed by DOC for reuse under the Creative Commons Attribution 4.0 International licence.
2017 | Threatened – Nationally Vulnerable | Qualifiers: DP, De
2012 | Not Threatened
2009 | Not Threatened
2004 | Not Threatened
Regional conservation statuses
Auckland: 2025 | At Risk – Regionally Declining | Qualifiers: DPR, DPS, DPT, PF, RF
The regional threat classification system leverages off the national assessments in the NZTCS, providing information relevant for the regional context. Auckland conservation status information is sourced from the “Conservation status of vascular plant species in Tāmaki Makaurau / Auckland” Simpkins E et al. (2025) report.
Referencing and citations
References and further reading
Allan HH. 1961. Flora of New Zealand, Volume I. Indigenous Tracheophyta: Psilopsida, Lycopsida, Filicopsida, Gymnospermae, Dicotyledones. Government Printer, Wellington, NZ. 1085 p.
Attribution
Fact sheet prepared for NZPCN by P.J. de Lange (5 January 2013). Description adapted from Allan (1961) supplemented with observations made from herbarium and fresh material.
Some of this factsheet information is derived from Flora of New Zealand Online and is used under a Creative Commons Attribution 3.0 New Zealand licence.
NZPCN Fact Sheet citation
Please cite as: de Lange, P.J. (Year at time of access): Metrosideros carminea Fact Sheet (content continuously updated). New Zealand Plant Conservation Network. https://www.nzpcn.org.nz/flora/species/metrosideros-carminea/ (Date website was queried)