How to Grow ʻŌkea
ʻŌkea
Xanthosoma sagittifolium
vegetableʻŌkea, also known as tannia or malanga, is a tropical aroid plant cultivated for its edible corms (underground tubers) and nutritious leaves. Native to tropical Central and South America, it thrives in warm, humid climates and is widely grown throughout the Pacific Islands, including Hawaiʻi. The plant produces arrow-shaped leaves and starchy corms used in various culinary traditions.
When should you plant ʻŌkea in your zone?
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Example ʻŌkea timeline · Pittsburgh, PA (Zone 6b)
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Plant ʻŌkea
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 ʻŌkea
Around Oct 14≈ 180 days after planting
Sample dates for Pittsburgh, PA. Sign up to get exact ʻŌkea dates for your own zip code.
Growing Conditions
Soil
Growing Zones
Find your zone →Thrives in zones 10-12; grown as annual in zone 9 with frost protection
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Get my ʻŌkea timeline →Growth Stages
Sprouting
2-4 weeksCormels begin to develop shoots and rootlets within 2-4 weeks of planting.
Ensure soil stays warm (70-80°F) and consistently moist. Provide shade cloth if necessary to prevent heat stress.
Vegetative Growth
6-12 weeksBroad arrow-shaped leaves unfurl and plant establishes strong foliage; stem thickens as plant matures.
Maintain consistent moisture and humidity. Feed with balanced fertilizer every 4-6 weeks. Mulch around base to retain moisture and suppress weeds.
Corm Development
8-16 weeksUnderground corms begin to enlarge as plant allocates more resources to storage organs; leaf growth continues above ground.
Reduce nitrogen slightly to encourage corm development rather than excess foliage. Continue regular watering and mulching.
Mature Growth
4-8 monthsPlant reaches maximum height (3-6 feet tall) with large leaves; corms reach harvestable size (4-12 inches long).
Continue watering and feeding. Monitor for pests and diseases. Leaves can be harvested for cooking while corms continue developing.
Harvest
Harvest periodCorms are ready for harvest when they reach desired size; foliage may begin to yellow slightly.
Carefully dig around plant to avoid damaging corms. Harvest when soil is workable to minimize damage. Store in cool, dry place.
Companion Planting
Plan your garden →Plant with:
Avoid planting near:
Common Pests
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Use virus-free planting material; remove infected plants immediately; control aphids which transmit virus
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Improve drainage and air circulation; remove infected leaves; apply copper-based fungicides; avoid overhead watering
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Ensure well-draining soil; avoid waterlogging; remove affected plant material; practice crop rotation
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Increase humidity through misting; apply insecticidal soap; spray with neem oil
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Remove with alcohol-soaked cotton swab; apply neem oil or insecticidal soap
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Hand-pick caterpillars; use Bacillus thuringiensis (Bt) spray; remove affected leaves
Uses
Staple starch and tuber vegetable
CulinaryʻŌkea corms are cooked similarly to potatoes or taro—boiled, baked, fried, or mashed—and are a dietary staple in Hawaiian and Pacific island cuisine. The young leaves are also edible when cooked and are rich in minerals and vitamins. [source]
Traditional medicine and nutritional support
MedicinalIn traditional Hawaiian and Pacific medicine, ʻŌkea has been used to support digestion and provide energy. The corms are high in fiber, potassium, and various nutrients beneficial for cardiovascular and digestive health. [source]
Food security and sustainability
HouseholdʻŌkea is highly productive in warm, wet climates and requires minimal inputs, making it an excellent crop for food sovereignty and sustainable agriculture in tropical and subtropical regions. [source]
Ecological benefit and pollinators
WildlifeThe plant's flowers attract various pollinators and beneficial insects, and its large leaves provide habitat and shade structure in garden ecosystems. [source]
Ornamental and cultural significance
CraftʻŌkea's large, distinctive arrow-shaped leaves make it an attractive ornamental plant in tropical gardens. It holds cultural significance in Hawaiian and Pacific Island heritage gardening. [source]
This is not medical advice. LizPlants is not a medical resource. Always consult a qualified healthcare professional before using plants medicinally.
Harvest Tips
Corms are typically ready to harvest 9-12 months after planting in warm climates, earlier in optimal conditions. Harvest when corms reach 4-12 inches in length. Dig carefully around the plant base to avoid bruising corms. Leaves can be harvested continuously throughout the growing season for cooking—pinch off outer, mature leaves while leaving inner ones for continued growth. For maximum corm yield, allow full maturation. Store harvested corms in a cool (55-60°F), dry place with good air circulation; they keep 2-4 months. In tropical areas where the plant is perennial, secondary cormels will develop and can be separated for propagation.
Fun Facts
- 🌱 ʻŌkea is called different names across the Pacific—in Hawaiʻi it's ʻŌkea, in the Caribbean and Central America it's called tannia or malanga, and it's closely related to taro (Colocasia esculenta), though with different flavor and texture characteristics.
- 🌱 The plant can produce edible leaves year-round in tropical climates, making it an excellent continuous harvest crop; some Hawaiian lo'i (taro patches) historically grew mixed plantings of taro, ʻōkea, and other aroids together.
- 🌱 ʻŌkea contains calcium oxalate crystals in raw form that can cause mouth irritation, but cooking completely breaks down these crystals, making the cooked corms and leaves completely safe and palatable.
Gardening Terms
New to gardening? Learn about terms used in this guide:
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