Kanawao: A Rare Hawaiian Native Worth Growing Responsibly
If you’re lucky enough to garden in Hawaii’s tropical climate, you might want to consider adding kanawao (Broussaisia arguta) to your landscape. This stunning native Hawaiian shrub offers both beauty and ecological value, though it comes with an important caveat that responsible gardeners should know about.
What Makes Kanawao Special
Kanawao is a perennial shrub that’s endemic to the Hawaiian Islands, meaning it exists nowhere else on Earth naturally. This multi-stemmed woody plant typically grows 13 to 16 feet tall, though it can occasionally reach greater heights under ideal conditions. What really sets kanawao apart are its large, broad leaves with prominent veining that create a lush, tropical appearance, complemented by clusters of white to cream-colored flowers that add subtle elegance to any garden.
Where Kanawao Grows Naturally
You’ll find kanawao growing naturally throughout the Hawaiian Islands in wet forest environments. It thrives as an understory plant in Hawaii’s native ecosystems, where it plays an important role in the island’s biodiversity.
Important Conservation Note
Before we dive into growing tips, there’s something crucial every gardener should know: kanawao has a Global Conservation Status of S3, which means it’s considered vulnerable. With typically only 21 to 100 occurrences and between 3,000 to 10,000 individuals remaining in the wild, this beautiful native needs our help.
If you decide to grow kanawao, please only source plants from reputable nurseries that propagate them responsibly. Never collect plants from the wild, as this could further threaten already vulnerable populations.
Why Grow Kanawao in Your Garden
There are several compelling reasons to consider kanawao for your Hawaiian landscape:
- Support native biodiversity and conservation efforts
- Attract native Hawaiian pollinators and birds
- Create authentic tropical garden aesthetics
- Add unique texture and form to shaded areas
- Contribute to native habitat restoration efforts
Perfect Garden Settings for Kanawao
Kanawao works beautifully in several garden types:
- Shade gardens where it can serve as a dramatic specimen plant
- Native Hawaiian gardens focused on indigenous species
- Tropical woodland landscapes
- Understory plantings beneath larger trees
- Conservation and restoration projects
Growing Conditions and Care
Kanawao is only suitable for USDA hardiness zones 10-12, making it exclusively a tropical and subtropical plant. Here’s what this Hawaiian native needs to thrive:
Light: Shade to partial shade – this understory plant doesn’t appreciate full sun
Soil: Moist, well-draining soil that mimics its natural wet forest habitat
Water: Consistent moisture is key, but avoid waterlogged conditions
Humidity: High humidity levels, which are naturally present in Hawaiian climates
Special considerations: Kanawao has a facultative wetland status in Hawaii, meaning it can handle both wet and drier conditions, though it prefers consistent moisture.
Planting and Care Tips
Successfully growing kanawao requires attention to its native habitat preferences:
- Plant in a location protected from strong winds
- Apply organic mulch around the base to retain moisture and suppress weeds
- Water regularly during dry periods, but ensure good drainage
- Avoid fertilizing heavily – native plants typically prefer lean soils
- Prune only as needed to maintain shape or remove damaged branches
Supporting Hawaiian Ecosystems
By choosing to grow kanawao responsibly, you’re doing more than just adding a beautiful plant to your garden. You’re supporting the conservation of Hawaii’s unique native flora and providing habitat for native pollinators and wildlife. The flowers attract various native Hawaiian insects and birds, making your garden a small but important piece of the larger ecosystem.
Remember, every native plant we grow responsibly is a small victory for conservation. Just make sure your kanawao comes from legitimate nursery sources, and you’ll be contributing to the preservation of this special Hawaiian treasure for future generations to enjoy.
