How to Grow Oha wai
iNaturalist
Oha wai
Clermontia arborescens
shrubOha wai is a rare Hawaiian endemic shrub in the Campanulaceae family, characterized by its distinctive tubular flowers and lush foliage. Native to the wet forests of Hawaii, particularly on the Big Island, Maui, and Molokai, it plays an important ecological role and holds cultural significance to Native Hawaiian communities. The plant produces beautiful purple to blue flowers that are adapted for pollination by Hawaiian birds.
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Example Oha wai timeline · Pittsburgh, PA (Zone 6b)
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Plant Oha wai
Around Apr 17Near Pittsburgh's average last spring frost.
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Tend & protect
Late spring–summerWatering, feeding, and pest-watch reminders.
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Harvest Oha wai
Late summer into fallBefore the first fall frost (≈ Nov 8)
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Growing Conditions
Soil
Growing Zones
Find your zone →Zones 10b-12; requires warm, humid tropical or subtropical conditions year-round
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Get my Oha wai timeline →Growth Stages
Seedling
6-12 weeksTiny seedlings with 2-4 cotyledons and first true leaves appearing; very delicate and slow-growing
Keep in high humidity environment (70-80%), use bottom heat (70-75°F), provide bright indirect light, use sterile seed-starting mix, maintain consistent moisture without waterlogging
Juvenile
6-12 monthsSmall plants with 4-8 true leaves, establishing root system; growth remains slow
Provide dappled light, maintain high humidity, fertilize monthly with diluted balanced fertilizer, protect from cold drafts, pot up when 2-3 inches tall
Vegetative
1-2 yearsYoung shrub with multiple stems and increasingly dense foliage; establishing branch structure
Increase spacing as plant grows, maintain humidity and consistent moisture, light fertilization every 4-6 weeks, prune lightly to encourage branching, protect from temperature fluctuations below 55°F
Flowering
Begins year 3-4, continuous with seasonal variationMature shrub producing distinctive purple to blue tubular flowers; may reach 6-12 feet in ideal conditions
Maintain consistent watering and humidity during flowering, reduce nitrogen fertilizer to encourage blooms, provide bright indirect light, pollinate by hand if no native pollinators present, deadhead spent flowers to encourage additional blooms
Fruiting/Seed Production
2-3 months after floweringSmall berry-like fruits develop after successful pollination, containing numerous tiny seeds
Allow some flowers to remain for seed development, collect seeds when fruits darken and appear mature, clean and dry seeds on paper before storage, refrigerate seeds in sealed containers
Companion Planting
Plan your garden →Plant with:
Avoid planting near:
Common Pests
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Increase humidity to 70%+ to deter; spray with water; use organic miticide if severe; avoid overhead watering that damages leaves
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Inspect regularly, remove by hand or with soft brush, spray with horticultural oil or neem oil, isolate infected plants
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Remove by hand or soft brush, apply horticultural oil in winter dormancy period, monitor closely
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Use yellow sticky traps, spray with organic insecticidal soap, increase air circulation while maintaining humidity
Uses
Traditional Hawaiian use
CulinaryOha wai has been used traditionally by Native Hawaiians as a food plant; the buds, flowers, and young leaves have been consumed as part of traditional Hawaiian diet and gather practices. [source]
Traditional Hawaiian medicine
MedicinalThe plant has been used in Hawaiian traditional medicine (lomilomi) practices, though specific medicinal applications require consultation with Hawaiian cultural practitioners. Modern scientific research on medicinal properties is limited. [source]
Native bird pollination
WildlifeThe tubular flowers are specifically adapted for pollination by endemic Hawaiian honeycreepers, particularly the i'iwi and apapane birds. Growing Oha wai supports conservation of Hawaiian native birds and ecosystems. [source]
Lei making and cultural crafts
CraftThe flowers have been used in traditional Hawaiian lei making and cultural practices. The plant is significant in Native Hawaiian culture and restoration efforts. [source]
Native ecosystem restoration
WildlifeOha wai is important for Hawaiian forest ecosystem restoration and reforestation projects. Growing and propagating this endangered species supports native habitat recovery efforts. [source]
This is not medical advice. LizPlants is not a medical resource. Always consult a qualified healthcare professional before using plants medicinally.
Harvest Tips
Seeds are ready to harvest when fruits darken and appear mature, typically 2-3 months after flowering. Collect entire fruits and allow to dry for 1-2 weeks. Extract seeds by carefully breaking open dried fruits and cleaning away pulp. Seeds are very small and require careful handling. Store dried seeds in refrigerator in sealed container for up to 1 year.
Fun Facts
- 🌱 Oha wai is found naturally only in the Hawaiian Islands and is endemic to specific wet forest ecosystems on the Big Island, Maui, and Molokai, making it an irreplaceable part of Hawaiian biodiversity.
- 🌱 The name 'Oha wai' translates to something related to the plant's habitat preference, reflecting its association with water and wet forest environments where it naturally thrives.
- 🌱 The plant's flowers are specifically adapted for bird pollination (ornithophily), showing co-evolution with Hawaiian honeycreepers, demonstrating the intricate relationships within Hawaiian native ecosystems.
Gardening Terms
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