Koolau Range Colicwood: A Rare Hawaiian Treasure for Your Native Garden
Meet the Koolau Range colicwood (Myrsine fosbergii), one of Hawaii’s most precious and endangered native shrubs. This little beauty might not be the showiest plant in the garden, but what it lacks in flash, it makes up for in ecological importance and quiet charm. If you’re passionate about Hawaiian native plants and conservation, this could be a meaningful addition to your landscape—but there’s a catch we need to talk about first.
What Makes This Plant Special?
The Koolau Range colicwood is a perennial shrub that typically grows as a multi-stemmed woody plant, usually staying under 13-16 feet tall. Its compact growth habit and small, oval leaves create a dense, attractive form that works beautifully in understory plantings. The tiny white to pinkish flowers may be modest, but they’re followed by small dark berries that add seasonal interest.
This shrub belongs to the Myrsine family and is sometimes known by its synonym Myrsine meziana var. fosbergii, though the accepted name remains Myrsine fosbergii.
A True Hawaiian Native
This plant is as Hawaiian as it gets—it’s endemic to the Koolau Range on Oahu, making it a true local treasure. You won’t find Myrsine fosbergii growing naturally anywhere else in the world, which makes it both incredibly special and incredibly vulnerable.
The Conservation Reality Check
Here’s where we need to have an honest conversation. The Koolau Range colicwood has a Global Conservation Status of S1, meaning it’s critically imperiled, and it’s listed as Endangered in the United States. With typically 5 or fewer occurrences and very few remaining individuals (fewer than 1,000), this plant is hanging on by a thread in the wild.
What this means for gardeners: If you’re considering growing this plant, you absolutely must source it responsibly from reputable native plant nurseries or conservation programs. Never collect from wild populations, and consider whether your garden can truly provide the specialized conditions this rare beauty needs to thrive.
Garden Role and Landscape Design
When grown successfully, the Koolau Range colicwood serves as an excellent understory shrub in Hawaiian native gardens. Its compact form and dense growth habit make it perfect for:
- Creating structure in shaded garden areas
- Supporting native ecosystem restoration projects
- Adding authentic Hawaiian character to native plant collections
- Providing habitat for native insects and birds
This isn’t a plant for formal landscapes or high-traffic areas. Instead, think of it as a specialized addition to conservation-minded gardens or authentic Hawaiian native plant displays.
Growing Conditions: Recreating the Koolau Mountains
The Koolau Range colicwood comes from Hawaii’s mesic to wet forests at elevations between 1,000-2,500 feet, and it’s pretty particular about its growing conditions. Here’s what it needs:
- Climate: USDA hardiness zones 10-11 only (think tropical to subtropical)
- Light: Partial shade to full shade—this is an understory plant
- Moisture: Consistently moist but well-draining soil
- Humidity: High humidity levels typical of Hawaiian forests
- Soil: Rich, organic soil that mimics forest floor conditions
The plant has a facultative wetland status in Hawaii, meaning it can handle both wetland and non-wetland conditions, but it definitely prefers consistent moisture.
Planting and Care Tips
Growing this endangered beauty requires dedication and the right setup:
- Plant in organic-rich, well-draining soil that stays consistently moist
- Provide protection from strong winds and direct sunlight
- Maintain high humidity around the plant—consider misting systems in dry climates
- Mulch heavily to retain moisture and suppress weeds
- Water regularly but avoid waterlogged conditions
- Be patient—rare plants often grow slowly and may take time to establish
Wildlife and Pollinator Benefits
While specific pollinator relationships aren’t well-documented for this rare species, the small flowers likely attract native Hawaiian insects. The berries may provide food for native birds, contributing to the broader ecosystem web that makes Hawaiian forests so special.
Should You Grow Koolau Range Colicwood?
This is a plant for serious native plant enthusiasts and conservationists. Consider growing it if you:
- Have experience with native Hawaiian plants
- Can provide the specific growing conditions it needs
- Are committed to conservation and can source plants responsibly
- Want to contribute to preserving Hawaii’s botanical heritage
Skip it if you’re looking for low-maintenance landscaping or live outside of tropical zones. This plant requires dedication and the right environment to succeed.
By choosing to grow responsibly sourced Koolau Range colicwood, you’re not just adding a unique plant to your garden—you’re becoming part of a conservation effort to save one of Hawaii’s rarest botanical treasures. That’s pretty special, even if your neighbors might not immediately understand why you’re so excited about your little shrub.
