Entelea arborescens
Entelea arborescens, commonly known as whau, is a species of malvaceous tree among New Zealand's native trees endemic to New Zealand. It is the sole species in the genus Entelea. It is a shrub or small tree, typically growing up to 8 meters (26 ft) tall, with an upright-oval habit. Its trunk can reach up to 0.25 meters in diameter. The tree has large (10–25 cm long), bright green, obliquely cordate (heart-shaped) leaves with 5 to 7 nerves and long petioles, giving it a tropical appearance. The leaves are soft, membranous, and can be glossy. White, scented flowers with yellow filaments are borne profusely between early spring and mid-summer. They are about 2 cm (0.79 in) in diameter and have 4 or 5 sepals and petals, with a dense central tuft of yellow stamens. The distinctive dry fruit capsules are brown, subglobose to globose, and covered with rigid, black to charcoal-colored spines that are 15-25 mm long. Entelea arborescens is notable for having one of the lightest known woods, sometimes even lighter than balsa wood, with a specific gravity less than that of cork. This wood was historically used by Māori for fishing floats and marker buoys. It grows in low forest along the coast of the North Island and the northern tip of the South Island of New Zealand, including the Poor Knights and Three Kings islands. It prefers sunny, free-draining soils but can tolerate semi-shade and seasonally damp ground. It is a fast-growing but short-lived species, typically living fewer than 15 years. Its seeds are long-lived and can be stimulated to grow by fire, allowing it to establish rapidly in disturbed areas. Entelea arborescens is frost-tender, tolerating temperatures down to 3°C. It can be grown outdoors in mild climates or in a conservatory. It prefers rich, moist loam and is intolerant of drought. It is easily propagated from seed.
| Scientific Name | Entelea arborescens |
|---|---|
| Height | 4-6 m |
| Spread | 3-5 m |
| Water Needs | Moderate |
| Light | Full sun to partial shade |
| Frost Tolerance | Low |
| Salt Tolerance | Moderate |
| Growth Rate | Fast |
| Lifespan | Medium |
Whau is a classic warm, coastal/lowland species. It thrives in frost‑free, humid districts with good summer moisture and shelter from strong winds. Juveniles are frost tender.
| City | Climate Suitability |
|---|---|
| Whangārei | Ideal |
| Auckland | Ideal |
| Hamilton | Ideal |
| Tauranga | Ideal |
| Rotorua | Ideal |
| Gisborne | Ideal |
| New Plymouth | Ideal |
| Napier | Ideal |
| Whanganui | Ideal |
| Palmerston North | Ideal |
| Wellington | Ideal |
| Nelson | Ideal |
| Christchurch | Ideal |
| Dunedin | Ideal |
| Invercargill | Ideal |
Prefers light, free‑draining, fertile soils with ample organic matter. Avoid heavy, cold, waterlogged clays. The very light timber reflects rapid growth in warm conditions.
Best in full sun to light shade with shelter. Exposure to strong winds tears the large leaves and stunts growth.
Maintain even moisture, especially in the first two summers. Short dry periods are tolerated once established, but regular watering promotes larger leaves and faster growth.
Whau produces exceptionally lightweight wood traditionally used for fishing floats and net corks. The species features in coastal restoration and heritage gardens for its tropical appearance.
Showy white flowers attract pollinators; seed capsules provide seasonal interest and food for some fauna. Rapid growth makes Whau a pioneer in sheltered sites.
Plant after last frost. Tip‑prune lightly to shape.
Water deeply in dry spells; stake young trees if windy.
Collect seed; reduce irrigation as temperatures cool.
Provide frost protection for juveniles in marginal climates.
Minimal pruning required for this fast-growing coastal native that can reach 6 metres in ideal conditions. Remove damaged or crossing branches and protect the large, soft leaves from strong winds which can tear and damage them extensively. Avoid heavy heading cuts which spoil the natural tropical form and can lead to weak regrowth in this lightweight-wooded species. Light tip-pruning in spring helps maintain compact growth and encourages bushier development, though whau naturally develops an attractive spreading canopy with age. Given its relatively short 15-20 year lifespan, focus on maintaining health and structural integrity rather than extensive pruning. Dead-heading spent flowers can redirect energy into foliage production, while removing lower branches improves air circulation around the distinctive heart-shaped leaves that characterize this unique New Zealand native.
Whau is a unique and fast-growing native shrub or small tree, highly valued for its exceptionally lightweight wood, large heart-shaped leaves, and tropical appearance. It is a pioneer species, rapidly colonizing disturbed sites in coastal and lowland forests. While it is a short-lived tree, its rapid growth and ability to establish quickly make it an excellent choice for early successional forest restoration and for adding a dramatic, exotic touch to sheltered gardens. Understanding its propagation methods is key to successfully growing this distinctive species.
Propagating Whau from seed is the most reliable and straightforward method. Collect the distinctive spiky seed capsules when they are mature and brown. Extract the seeds and sow them promptly in a well-draining seed-raising mix, lightly covering them. Whau seeds are known to have a hard seed coat, and germination can be improved by scarification (lightly sanding or nicking the seed coat) or by soaking the seeds in warm water for 24 hours before sowing. Maintain consistent moisture and provide warm, bright conditions for germination. Germination typically occurs readily in warm conditions, often within a few weeks. Once seedlings have developed a few true leaves, they can be potted into individual containers and grown in a sheltered, frost-free location before planting out.
Whau can also be propagated from semi-hardwood cuttings, typically taken in late summer or early autumn from healthy, current season's growth. Cuttings should be about 6-8 inches long. Remove the lower leaves and dip the cut end in a rooting hormone. Plant the cuttings into a well-draining, sterile cutting mix, such as a blend of perlite and sand. Maintain high humidity around the cuttings, perhaps by placing them under a plastic dome or in a propagator, and provide bottom heat to encourage root development. Keep the medium consistently moist but not waterlogged. Rooting can be slow and success rates can vary, making this method more suitable for experienced propagators.
Whau (Entelea arborescens) is a fast-growing, short-lived native tree endemic to New Zealand, renowned for its exceptionally lightweight wood and large, heart-shaped leaves. This distinctive native tree grows naturally in coastal and lowland forests, particularly in disturbed areas and forest margins, where it acts as a pioneer species. The plant produces clusters of delicate white flowers in spring, followed by distinctive spiky seed capsules. Traditionally valued by Māori for its buoyant wood, used for fishing floats and net markers, Whau is also appreciated in modern gardens for its tropical appearance and rapid growth. Its ecological role as a quick-growing colonizer and provider of habitat makes it important for early successional forest restoration.
Whau (Entelea arborescens) has cultural and ecological significance in Aotearoa New Zealand. It supports native biodiversity, contributes to habitat structure, and is valued in restoration and garden plantings. Within mātauranga Māori, native plants like this help sustain the health of the ngahere (forest) and local ecosystems.
