Metrosideros kermadecensis W.R.B.Oliv.

Kermadec pōhutukawa

New Zealand endemic.

Easily propagated from fresh seed. Widely planted in mainland New Zealand from, seemingly, a single clone. The clone is slow growing and forms large shrubs, or compact trees with time. Cultivars with various variegations have been selected, including M. kermadecensis ‘Lewis Nicholls’, ‘Radiant’, ‘Red and Gold’, ‘Sunninghill’ and ‘Variegata’.

Endemic to the northern Kermadec Island group. However, widely cultivated in New Zealand (North Island especially), also in Australia and Norfolk Island.

• Reddish aerial roots.
• Lower surface of leaves mostly velvety.
• Leaf tips rounded or slightly notched.
• Leaves sub-orbicular, broadly ovate to elliptic-oblong.
• Flowers crimson (rarely pink).
• Flower stalks stout.
• Flower-cluster stalks, individual flower stalks, base of flowers and outer surface of sepals all with long, copious hairs.
• Stamens 10–23 mm long.

Tree up to 20 m tall in the wild (in cultivation to 10 m tall), with large canopies, often multi-trunked from base. Branches spreading, and often bearing aerial roots.

Bark firm, grey to grey-brown. Branchlets very hairy, becoming hairless with age. Sometimes branches spreading and rooting where touching the ground.

Leaves arranged in opposite pairs, each pair being at right angles to the pair below, leathery, sub-orbicular, broadly ovate to elliptic-oblong, (20–)25–50 mm long, 10–20(–30) mm wide, upper surface dark green, paler below (mainly due to thick layer of grey-white hairs), leaf surface flat, not puckered, upper surface at first hairy, becoming hairless with age, lower surface mostly velvety, midrib raised, oil glands not readily visible on either surface; margins entire, but slightly rolled downwards (revolute), tips rounded or notched, leaf stalks ± 7–9 mm long, hairy.

Flowers in rounded terminal clusters, cluster-branchlets often 3-flowered, or flowers solitary on cluster axis. Flowers ± 6–8 mm in diam., mature flower stalks absent to ± 2 mm long, ± 1.5 mm wide, petals 5, crimson; sepals 5, tips free, persistent, stalks and base of flowers and outer surface of sepals all with long, copious hairs; stamens crimson (rarely pink), filaments 10–23 mm long, much longer than petals. Main flowering period: throughout the year.

Fruit dry, densely hairy, ± 5–8 mm wide, capsule dome raised above the calyx tube, calyx tube as wide as fruit, seeds released through open valves.

Of the New Zealand species M. kermadecensis is most similar to M. excelsa in that both have velvety lower leaf surfaces, but differs in that the former possesses smaller leaves and relative to its length, wider leaves (up to 50 mm long and up to 30 mm wide, as opposed to up to 120 mm long and up to 60 mm wide), and shorter stamens (filaments 10–23 mm long as opposed to 30–40 mm long).

As M. kermadecensis is naturally endemic to the Kermadec Islands where it is being impacted by myrtle rust (caused by Austropuccinia psidii), it was given a conservation status of Threatened – Nationally Critical in 2018.

Hybridises in cultivation with M. excelsa.

Metrosideros is a genus of more than 50 species of trees, shrubs and vines, mostly found in the Pacific region. New Zealand is well represented by having 12 endemic species.

• CitSciHub
• Flora of New Zealand Online
• GBIF
• iNaturalist NZ
• NZPCN