Puka
Meryta sinclairii
Meryta sinclairii , commonly known as Puka or Pukanui, is an iconic and highly distinctive broadleaved evergreen tree endemic to the Three Kings Islands (Manawatāwhi), a small group of islands off the northern tip of New Zealand. This magnificent tree is renowned for its extraordinarily large, glossy leaves and robust, architectural form, making it a dramatic focal point in subtropical and coastal gardens. As a critically endangered species in the wild, it holds significant conservation importance.
Plant Description
Meryta sinclairii typically grows as a small, stout-trunked tree, reaching up to 6-8 meters in height, though it can be smaller in cultivation. Its most striking feature is its massive, leathery, dark green leaves, which are the largest of any native New Zealand tree. These leaves are oblong to ovate, sometimes reaching up to 50 cm long and 20 cm wide, with prominent venation. The tree has a distinctive architectural form, often sparsely branched with leaves clustered at the branch tips. It produces panicles of small, greenish-white flowers in summer, followed by clusters of small, black, fleshy fruit that are attractive to birds.
Quick Facts
| Scientific Name | Meryta sinclairii |
|---|---|
| Family | Araliaceae |
| Form | Broadleaved evergreen tree |
| Light | Partial shade to full sun (prefers dappled light when young) |
| Soil | Moist, well-drained, rich in organic matter |
| Water | Moderate to high |
| Water Needs | Moderate |
| Frost Tolerance | Frost Tender |
| Salt Tolerance | High |
| Height | Up to 8 m |
| Spread | 3-5 m |
| Flowering Season | Summer |
| Fruit/Berry Season | Autumn/Winter |
| Foliage | Evergreen; extraordinarily large, glossy, dark green leaves |
| Growth Rate | Moderate |
| Lifespan | Long-lived perennial |
| Unique Features | Largest leaves of any native New Zealand tree; critically endangered in wild. |
Climate Best Suited to
Meryta sinclairii , the puka, requires warm, humid, frost-free conditions typical of northern coastal forests. This tropical-looking tree thrives in areas with mild winters (minimum 5°C), warm summers, and high humidity. It performs best in regions with 1000-1500mm annual rainfall and protection from cold winds and frost.
Regional Suitability
| City | Climate Suitability |
|---|---|
| Whangārei | Ideal |
| Auckland | Ideal |
| Hamilton | Suitable |
| Tauranga | Ideal |
| Rotorua | Marginal |
| Gisborne | Suitable |
| New Plymouth | Suitable |
| Napier | Marginal |
| Whanganui | Marginal |
| Palmerston North | Unsuitable |
| Wellington | Marginal |
| Nelson | Marginal |
| Christchurch | Unsuitable |
| Dunedin | Unsuitable |
| Invercargill | Unsuitable |
Habitat
Natural Distribution
In the wild, Meryta sinclairii is naturally restricted to a very small population on the Three Kings Islands (Manawatāwhi), off the northern coast of New Zealand. It grows in sheltered forest environments, often on steep, rocky slopes and gullies, where it is protected from the harshest winds and retains good humidity. Its limited natural range makes its wild population extremely vulnerable.
Conservation Status
Current Threats and Protection
Meryta sinclairii is classified as "Nationally Critical" under the New Zealand Threat Classification System. It is one of New Zealand's rarest trees, with only a few mature wild specimens remaining on the Three Kings Islands. Threats include historical habitat destruction (by introduced goats, now eradicated) and its extremely limited natural range. Intensive conservation efforts, including strict protection of its island habitat and ex-situ cultivation, are critical for its survival.
How to Grow
Cultivation Requirements
Meryta sinclairii thrives in warm, humid, frost-free environments. It requires moist, well-drained soil rich in organic matter. Young plants prefer partial shade and shelter from wind and direct, harsh sunlight, while mature trees can tolerate more sun if adequate moisture is available. Protect from strong winds, which can shred its large leaves, and from any frost, especially when young. Regular watering is essential, particularly during dry periods.
Planting Guide
Best Planting Practices
Plant Meryta sinclairii in spring in a sheltered, frost-free location with partial shade, gradually acclimating it to more sun if desired as it matures. Prepare a large planting hole, enriching the soil with plenty of well-rotted compost. Ensure good drainage, as it does not tolerate waterlogging. Water deeply after planting and maintain consistent moisture. Mulch well to keep the root zone cool and moist. Provide wind protection, especially during establishment.
Ecological Role
Environmental Benefits
Despite its critically endangered status in the wild, Meryta sinclairii plays an ecological role on the Three Kings Islands as a component of the native forest ecosystem. Its flowers provide nectar for insects, and its fruit is a food source for native birds, which in turn aid in seed dispersal. Its large leaves contribute to the understory shade and litter layer, contributing to soil health.
Uses
Traditional and Modern Applications
Meryta sinclairii is primarily valued as an ornamental tree for subtropical and warm-temperate gardens, particularly in frost-free coastal areas. Its dramatic foliage and architectural form make it an outstanding specimen plant, focal point, or tropical accent. It is also of immense scientific and conservation interest due to its rarity and unique evolutionary history.
Landscaping Uses
Garden Design Applications
Puka is an exceptional specimen tree for sheltered, frost-free gardens in subtropical and warm-temperate climates. Its bold, architectural form and giant leaves create a dramatic, tropical effect. It is ideal as a focal point, in courtyards, or planted against a plain wall to highlight its unique silhouette. It can also be grown in large containers.
Seasonal Care
Year-Round Maintenance
Meryta sinclairii requires consistent moisture, especially during dry periods. Protect young plants from any frost. Fertilize lightly in spring with a balanced slow-release fertilizer suitable for native plants. Monitor for pests and diseases, particularly in humid conditions. In cooler climates, grow in a sheltered spot or in a pot that can be moved indoors for winter.
Pruning
Pruning Techniques
Minimal pruning is typically required for Meryta sinclairii to maintain its natural form. Remove any dead, damaged, or diseased branches as needed. Light shaping can be done to encourage a denser habit or to remove lower branches for trunk development. Avoid heavy pruning, as it can stress the tree.
How to Grow Puka
From Seed
Propagation of Meryta sinclairii from seed is a common and effective method. Collect seeds from ripe fruit in autumn/winter. Clean the fleshy pulp from the seeds thoroughly, as this can inhibit germination. Sow fresh, cleaned seeds into a well-draining seed-raising mix. A period of warmth (around 20-25°C or 68-77°F) and consistent moisture is usually required for germination, which can be erratic and sometimes slow, taking several weeks to a few months. Once seedlings are robust enough to handle, prick them out into individual pots and grow them on in a warm, sheltered, and bright location, protecting them from direct sunlight and frost.
From Cuttings
Meryta sinclairii can be successfully propagated from semi-hardwood cuttings. Take cuttings about 15-20 cm long from healthy, non-flowering shoots in late spring or summer. Remove the lower leaves and dip the cut end in a rooting hormone to encourage root development. Insert the cuttings into a free-draining rooting medium such as a mix of sand and perlite. Provide high humidity around the cuttings, either by placing them in a propagation chamber or covering them with a plastic bag, and ensure consistent moisture in the rooting medium. Keep in a warm, bright location out of direct sunlight. Rooting typically occurs within 8-12 weeks. Once rooted, gradually acclimatize plants to ambient conditions before potting up.
General Cultivation
Puka (Meryta sinclairii) is an iconic tree that thrives in warm, humid, frost-free environments, making it suitable for subtropical and coastal gardens. It requires moist, well-drained soil rich in organic matter; prepare the planting site with plenty of well-rotted compost. Young plants prefer partial shade and shelter from strong winds and harsh, direct sunlight. As they mature, trees can tolerate more sun if adequate moisture is available. Protection from strong winds is crucial, as its large leaves can be easily damaged. It is frost tender, so protect from any frost, especially when young, or grow in a container that can be moved indoors in colder climates. Regular watering is essential, particularly during dry periods. Mulch well to keep the root zone cool and moist. Minimal pruning is required; remove dead or damaged branches and light shaping can be done to encourage a denser habit.
Pests and Diseases
Common Problems and Solutions
Meryta sinclairii is generally a robust tree when grown in optimal conditions. The main issues are related to environmental stress: frost damage, windburn on its large leaves, and root rot in poorly drained soils. Scale insects or mealybugs may occasionally appear, but these are usually manageable. Ensure good air circulation and well-drained soil to prevent fungal issues.
Cultural Significance
Traditional Uses and Values
Meryta sinclairii , or Puka (Pukanui), holds significant cultural value for Māori, particularly due to its restricted and sacred status as a species endemic to the Three Kings Islands (Manawatāwhi). The islands themselves are steeped in Māori tradition and spiritual importance. As one of New Zealand's rarest native trees, Puka is considered a taonga (treasure) and a symbol of conservation efforts for unique indigenous flora. Its large, distinctive leaves are also recognized for their beauty and uniqueness.
Bonus Tip
Expert Growing Advice
To provide the best growing conditions for Meryta sinclairii , particularly in areas outside of its natural subtropical habitat, mimic a sheltered forest understory by providing overhead shade and protection from strong winds, especially when the plant is young. A rich, organic mulch will help maintain soil moisture and coolness, promoting healthy growth.
