Weinmannia racemosa
Kāmahi is a fast-growing evergreen tree reaching 15-25 meters tall, distinguished by its compound leaves with serrated leaflets and spectacular displays of creamy-white flowers that cover the entire crown in spring and summer. This adaptable species has attractive reddish-brown bark and serves as an excellent pioneer tree for revegetation projects. Found throughout New Zealand's lowland and montane forests, it produces abundant nectar that attracts native birds and beneficial insects, making it invaluable for both ecological restoration and garden wildlife among New Zealand's native trees
Image credit: Kāmahi (Weinmannia racemosa). Wikipedia
| Scientific Name | Weinmannia racemosa |
|---|---|
| Height | 15-25 meters |
| Spread | 8-15 meters |
| Water Needs | Moderate to high |
| Light | Full sun to partial shade |
| Frost Tolerance | Moderate (hardy to -8°C) |
| Salt Tolerance | Low |
| Growth Rate | Fast |
| Lifespan | 100-200 years |
Kāmahi grows throughout New Zealand from sea level to 1100 meters elevation in lowland and montane forests. It thrives in cool, moist climates with regular rainfall and performs best in areas with mild temperatures and high humidity. This adaptable species tolerates a range of conditions but struggles in very dry or very hot locations.
| 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 | Moderate |
Kāmahi is adaptable to various soil types but prefers fertile conditions:
Kāmahi performs well in various light conditions:
Kāmahi requires consistent moisture for optimal growth:
This versatile native plant offers multiple practical applications in landscaping and garden design, from providing ground cover and erosion control to creating habitat for native wildlife. The plant's natural characteristics make it valuable for restoration projects and sustainable gardening practices.
Kāmahi naturally develops good form but may benefit from light pruning:
Use sharp, clean tools and make cuts just outside the branch collar. Kāmahi has excellent wound response and tolerates pruning well, making it suitable for size management.
Plant Kāmahi during autumn or spring when soil conditions are optimal. This fast-growing species establishes quickly when planted during favorable weather conditions.
Choose a site with:
Provide regular watering during first 2-3 years until established. Kāmahi's fast growth means it quickly becomes self-sufficient but benefits from consistent care during establishment.
Kāmahi propagates readily from seed with good germination rates:
Seedlings grow rapidly and may flower within 5-8 years under good conditions.
Vegetative propagation is moderately successful:
This native species has been part of New Zealand's natural heritage for thousands of years, contributing to the unique ecosystems that characterized the country before human settlement. The plant's evolutionary adaptations reflect the distinctive environmental conditions and ecological relationships of its native habitat.
Kāmahi's vigorous growth means it typically recovers well from pest damage. Focus on maintaining good growing conditions for natural pest resistance.
Time your garden visits to coincide with Kāmahi's spectacular flowering season (November to February). The entire tree becomes covered in masses of creamy-white, fragrant flowers that attract an incredible diversity of native birds, bees, and butterflies. Early morning is particularly magical when the flowers are fresh and bird activity is at its peak.
Learn more about the cultural significance of native trees in Cultural Plants.
This section provides important information about plant care and cultivation practices. Understanding these aspects helps ensure successful growth and development in garden conditions.
This section provides important information about plant care and cultivation practices. Understanding these aspects helps ensure successful growth and development in garden conditions.
This section provides important information about plant care and cultivation practices. Understanding these aspects helps ensure successful growth and development in garden conditions.
This section provides important information about plant care and cultivation practices. Understanding these aspects helps ensure successful growth and development in garden conditions.
Kāmahi serves as a dominant canopy species in many New Zealand forests, creating important habitat structure and food resources through its abundant nectar-rich flowers that support numerous native birds, bees, and other pollinators. The tree plays crucial roles in forest succession, often forming pure stands in regenerating areas while providing nurse habitat for other forest species to establish. Its dense foliage supports diverse epiphyte communities and provides nesting sites for native birds, while the extensive root system helps stabilize forest soils and maintain watershed integrity in both lowland and montane forest ecosystems.
This section provides important information about plant care and cultivation practices. Understanding these aspects helps ensure successful growth and development in garden conditions.
This section provides important information about plant care and cultivation practices. Understanding these aspects helps ensure successful growth and development in garden conditions.
Kāmahi is not currently threatened and remains widespread throughout New Zealand's forests, demonstrating good adaptability to various forest environments and natural disturbances. However, browsing pressure from introduced mammals, particularly deer and possums, can impact regeneration and canopy health, while habitat fragmentation reduces its ability to form the large forest stands that characterize healthy native ecosystems. Conservation efforts focus on managing mammal pests, protecting large forest blocks, and promoting the species' use in forest restoration where its ecological roles as a nurse species and wildlife habitat provider make it essential for successful ecosystem recovery.
This plant has cultural associations in Aotearoa and is valued in restoration and gardens for ecological services; use eco‑sourced stock near natural areas.
Kāmahi holds significant cultural importance for Māori as both a practical resource and a symbol of forest health, with the hard, fine-grained timber being used for making tools, weapons, and implements, while the astringent inner bark provided important medicinal applications for treating various ailments including stomach problems and wounds. The tree's abundant white flowers, which can cover entire canopies in spectacular displays, were recognized in traditional ecological calendars as markers of seasonal abundance and forest health. The species continues to hold cultural significance as an indicator of pristine native forest conditions and remains valued in contemporary restoration and cultural practices.
This section provides important information about plant care and cultivation practices. Understanding these aspects helps ensure successful growth and development in garden conditions.
This section provides important information about plant care and cultivation practices. Understanding these aspects helps ensure successful growth and development in garden conditions.
