‘Blue Hawaii’ Elephant Ear (Colocasia esculenta ‘Blue Hawaii’) is a distinctive tropical ornamental plant. A cultivar of the taro plant, it is popular for its dramatic foliage and striking appearance, adding a bold statement to any garden or landscape.
Distinctive Appearance
The ‘Blue Hawaii’ Elephant Ear boasts captivating, large, heart-shaped to arrow-shaped leaves. These leaves have a vibrant green base with prominent dark blue-black or deep purple-black veins and undulating margins. Held on semi-glossy, dark burgundy stems, the leaves can reach 2 feet long. The plant grows to about 5 feet tall and 2 feet wide, making it a focal point in any garden or container display.
Optimal Growing Conditions
Light Needs
‘Blue Hawaii’ Elephant Ear thrives in bright, indirect light or partial shade. While it tolerates some full sun in cooler climates, direct afternoon sun in hot regions can scorch leaves. Insufficient light diminishes vigor and vibrant leaf coloration. A sheltered spot protects its large leaves from strong winds.
Watering Practices
This water-loving plant requires consistently moist soil to flourish. Regular watering ensures the soil never fully dries out, but avoid waterlogging to prevent root rot. ‘Blue Hawaii’ can even grow as a marginal plant in up to 6 inches of standing water, highlighting its preference for abundant moisture.
Soil Preferences
Ideal soil for ‘Blue Hawaii’ is rich, organically fertile, and well-draining. A mix high in organic matter, such as compost or well-rotted manure, improves fertility and moisture retention while allowing for adequate drainage. Good drainage prevents water accumulation around the corms, yet the soil must retain enough moisture for the plant’s high water demands.
Temperature and Humidity
As a tropical plant, ‘Blue Hawaii’ prefers warm, humid conditions. Optimal growth temperatures range between 68°F and 86°F (20°C and 30°C). Temperatures below 50°F (10°C) can cause damage, as the plant is not frost-tolerant. Indoors, maintain high humidity through misting or a humidifier for healthy foliage.
Fertilization
‘Blue Hawaii’ is a heavy feeder, benefiting from regular nutrient replenishment during its active growing season. Apply a balanced, water-soluble fertilizer every two to four weeks from spring through summer to encourage vigorous growth, vibrant foliage, and a more impressive overall plant size.
Planting and Winter Care
‘Blue Hawaii’ Elephant Ear can be planted directly in the ground in USDA hardiness zones 8 to 11, where it behaves as a perennial and tubers remain year-round. In colder regions, container planting allows the plant to be moved indoors when temperatures drop. When planting, dig a hole roughly twice the root ball size, backfilling with amended soil for a healthy start.
In regions with cold winters (below USDA Zone 8), ‘Blue Hawaii’ is grown as an annual or requires overwintering. Before the first hard frost (when temperatures consistently fall below 50°F / 10°C), carefully dig up the corms. After lifting, clean off excess soil and dry them for a few days to prevent rot during storage. Store them in a cool, dry, frost-free location (above 45°F / 7°C), such as a garage or basement, often nestled in peat moss or wood shavings, until spring.
Potential Issues and Safety
Common pests affecting ‘Blue Hawaii’ Elephant Ear include spider mites and aphids, managed by regular inspection and insecticidal soap. Root rot can occur from overwatering or poorly draining soil.
All parts of Colocasia esculenta, including ‘Blue Hawaii’, contain calcium oxalate crystals. If ingested, these crystals cause irritation and burning in the mouth and throat, leading to symptoms like stomach upset, swelling, and difficulty swallowing. Keep the plant away from children and pets. Wear gloves when handling to prevent skin irritation.