Whau
Entelea arborescens
This native plant, known as Whau(scientific name: Entelea arborescens ), is a remarkable species endemic to New Zealand. It is characterized by its unique features, ecological role, and cultural significance. This comprehensive guide provides detailed information on its care, propagation, and importance within the New Zealand ecosystem. Understanding this plant contributes to the appreciation of our rich biodiversity and heritage, and supports conservation efforts for Browse All .
Plant Description
Identification and Physical Characteristics
Entelea arborescens , commonly known as Whau, is a species of malvaceous tree endemic to New Zealand and the sole species in the genus Entelea Discover more about native grasses. It is a shrub or small tree, typically growing up to 8 meters tall, with an upright-oval habit and a trunk that 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, about 2 cm in diameter. The distinctive dry fruit capsules are brown, subglobose to globose, and covered with rigid, black to charcoal-coloured spines that are 15-25 mm long. Whau is notable for having one of the lightest known woods, sometimes even lighter than balsa wood. It grows in low forest along the coast of the North Island and the northern tip of the South Island of New Zealand, preferring sunny, free-draining soils but tolerating semi-shade and seasonally damp ground. It is a fast-growing but short-lived species, typically living fewer than 15 years, with seeds that can be stimulated to grow by fire.
Quick Facts
| 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 |
Climate Best Suited to
Entelea arborescens is well adapted to various New Zealand regions.
Regional Suitability
| City | Climate Suitability |
|---|---|
| Auckland | High |
| Wellington | High |
| Christchurch | Medium |
Plant Habitat
Natural Occurrence and Ecology
Entelea arborescens , also known as whau, is a species of tree endemic to New Zealand. It is typically found in coastal to lowland forest or shrubland, often in open sites such as around recent slips, tree falls, cliff faces, boulder slopes, sand dunes, or on the margins of streams, rivers, lagoons, and lakes.Its natural distribution includes the Three Kings Islands, the North Island (north of the Māhia Peninsula and Kawhia Harbour, and sparsely south of this), and the northern tip of the South Island, specifically around Golden Bay / Mohua and Nelson. Some inland and southern North Island occurrences are believed to be from deliberate plantings by Māori.
Growing Requirements
Soil Requirements
Prefers well-draining soil rich in organic matter.
- Well-drained
- Loamy
Light Requirements
Grows best in partial to full sun.
- Full Sun
- Partial Shade
Water Requirements
Requires regular watering during dry periods.
- Regular
- Drought tolerant once established
Planting and Establishing
Establishment Guidance
Plant Entelea arborescens in a hole twice the width of the root ball.
Proper establishment is key to long-term success. Ensure the planting hole is twice as wide as the root ball and backfill with a mix of native soil and organic compost. Initial watering should be thorough, followed by regular monitoring during the first two growing seasons to ensure the plant becomes well-anchored and resilient to local climate fluctuations.
Ecological Role
Biodiversity and Ecosystem Impact
Provides habitat and food for native fauna.
This species plays a vital role in its local ecosystem, providing essential habitat and food sources for native biodiversity. Its presence supports complex ecological interactions, contributing to the overall health and stability of the environment. By planting this native, you help maintain the intricate web of life that defines New Zealand's unique natural heritage.
Uses & Significance
Garden Uses
Ideal for rock gardens and native borders.
- Rock gardens
- Ground cover
Ecological Value
Supports local pollinators.
- Birds
- Insects
The versatility of this plant makes it a valuable addition to many New Zealand gardens. Beyond its aesthetic appeal, it offers practical benefits such as soil stabilization and shelter for smaller plants. Its historical and modern uses highlight its enduring importance in both traditional practices and contemporary landscape design, making it a thoughtful choice for any restoration or gardening project.
Landscaping Uses
Adds texture and form to modern landscapes.
In a landscape setting, this plant provides excellent structure and year-round interest. Its unique form and foliage can be used to create focal points or as a cohesive element in a larger native planting scheme. It pairs well with other New Zealand natives, allowing for the creation of diverse and resilient garden environments that reflect the natural beauty of Aotearoa.
Seasonal Care Calendar
Spring
Mulch and apply balanced fertilizer.
- Fertilize
- Mulch
Summer
Water deeply during dry spells.
- Water
- Check for pests
Autumn
Tidy up any dead foliage.
- Prune lightly
- Plant new specimens
Winter
Protect from heavy frosts if necessary.
- Frost protection
When to Prune and How Much
Minimal pruning required to maintain shape.
- Remove dead branches
Always use clean, sharp tools.
Regular maintenance through careful pruning ensures the plant remains healthy and maintains its desired shape. Focus on removing dead or diseased wood to promote better air circulation and prevent the spread of pathogens. Proper pruning techniques help the plant direct its energy toward new growth, resulting in a more robust and aesthetically pleasing specimen in your garden.
How to Grow Whau
Cultivating Entelea arborescens ( Entelea arborescens ) is a rewarding endeavor for any gardener interested in New Zealand's unique flora. This species can be propagated through several methods, each requiring specific conditions to ensure healthy growth and establishment. Successful propagation depends on mimicking the plant's natural environment and providing consistent care during the early stages of development.
From Seed
Propagation from seed is often the most effective way to produce a large number of Entelea Arborescens plants. Seeds should be collected when they are fully mature. Freshly collected seeds generally have higher germination rates than those that have been stored for long periods.
Sow fresh seeds in a seed-raising mix.
- Collect seeds
- Sow in trays
Keep moist until germination.
From Cuttings
For those wishing to replicate specific characteristics of a parent plant, vegetative propagation via cuttings is the preferred method. This technique ensures that the new plants are genetically identical to the source. Semi-hardwood cuttings taken during the appropriate season usually yield the best results for this species.
Take semi-hardwood cuttings in late summer.
- Take cuttings
- Use rooting hormone
Additional Methods
Depending on the growth habit of Entelea arborescens , other methods such as division or layering might also be viable options. Division is particularly suitable for plants that form dense clumps or have spreading root systems, while layering can be used for species with trailing or flexible stems.
Division can be done in early spring.
- Divide clumps
- Replant immediately
Pests & Diseases
Generally resistant to major pests.
While generally resilient, maintaining optimal growing conditions is the best defense against pests and diseases. Regular monitoring allows for early detection of any issues, which can often be managed through cultural practices or organic interventions. Ensuring good air circulation and appropriate watering will significantly reduce the plant's susceptibility to common environmental stresses and pathogens.
Cultural Significance
Entelea arborescens , commonly known as whau, holds significant cultural importance, particularly for the Māori people of New Zealand. Its cultural value stems primarily from the unique properties of its wood and other plant parts.Lightweight Wood for Fishing and Rafts:The whau produces one of the lightest woods in the world, even lighter than cork. This made it an invaluable resource for Māori, who used it extensively for fishing net floats (pōito), marker buoys (kārewa), and to construct small rafts (mōkihi) for activities like crayfish hunting.Cultivation and Distribution:The plant was so highly valued that Māori actively cultivated it in some areas. Evidence suggests that Māori horticulturalists may have transported and planted whau in new locations before European settlement, contributing to its distribution beyond its natural boundaries. For instance, Auckland's iconic Mt. Eden is known in Māori as Maungawhau, meaning "The Mountain of the Whau Tree," indicating its historical abundance in the area.Traditional Games and Tools:Small carved pieces of whau wood were used in traditional catching games. The wood was also used for darts (teka) and poi. Long fibers from the trunk were utilized for fishing lines.Medicinal Uses:The sap of the whau was used in the North Island to preserve bodies, and its leaves were employed to treat piles. The jelly found beneath the bark was also used to alleviate difficult childbirth. Heated leaves were made into a poultice for treating wounds and sores.Writing Material:The large, soft leaves of the whau were sometimes used as a substitute for paper for writing notes and love letters, with a sharp object serving as a stylus.Etymology:The common name "whau" is a Māori word believed to be derived from the common Polynesian word for hibiscus, "fau," due to a superficial resemblance.
- Traditional medicine
- Crafts
Bonus Tip
Excellent for low-maintenance gardens.
For an extra boost, consider applying a thin layer of high-quality organic mulch around the base of the plant. This helps retain soil moisture, suppresses weeds, and gradually improves soil structure as it breaks down. This simple step can make a significant difference in the plant's overall vigor and resilience, especially during periods of extreme weather.
Related Plants
Explore other native plants that share similar characteristics or habitats with Entelea Arborescens ( Entelea arborescens ), offering further insights into New Zealand's diverse flora. These related species provide context and opportunities for complementary planting in your garden.
Plant Conservation
Conservation Status
The conservation status of Entelea arborescens , also known as whau, is generally "Not Threatened" at a national level in New Zealand, according to assessments in 2013, 2018, and 2023.However, there is a regional classification for Auckland in 2025 that lists Entelea arborescens as "At Risk - Regionally Declining". This regional decline is attributed to factors such as browsing pressure from cattle, goats, and horses, clearance of coastal scrub for housing, and the spread of invasive woody shrubs and trees. Despite these regional threats, the species is endemic to New Zealand and can be found across the North Island, the northern tip of the South Island, and the Three Kings Islands. It is a fast-growing, short-lived tree that naturalizes easily.