About

Alocasia macrorrhizos is a tropical perennial characterized by its large, shiny, dark green foliage. The leaves, featuring light green veins, can grow up to 1.2 meters in length and are supported by upright petioles that also reach approximately 1.2 meters high. During the summer, it may develop pale green flowers. Commonly referred to as giant taro, this plant is extensively grown and established in tropical regions for its edible tubers, which necessitate thorough cooking before consumption. In cooler climates, it can serve as a unique addition to conservatories.

About the genus

Alocasia consists of sturdy, evergreen perennials that develop rhizomes or tubers. They feature large, typically peltate leaves marked by prominent veins. While their flowers are somewhat inconspicuous, they can give rise to orange-red fruits.

Growing conditions

Sunlight
Partial shade
Soil type
Loam, Sand
Soil pH
Acid, Alkaline, Neutral
Soil moisture
Moist but well-drained
Aspect
East-facing, South-facing, West-facing
Exposure
Sheltered
UK hardiness
H1A

Plant details

Plant type
Conservatory Greenhouse
Habit
Columnar upright
Foliage
Evergreen
Height
1.5-2.5 metres
Spread
1.5-2.5 metres
Time to full height
2-5 years
Suggested uses
Architectural, City and courtyard gardens, Patio and container plants, Sub-tropical
Native to
C Malesia to NE Australia
Toxicity
TOXIC if eaten, skin/eye irritant. Wear gloves and other protective equipment when handling. TOXIC to pets - see the HTA guide to potentially harmful plants for further information and useful contact numbers

Care notes

Cultivation
Grow indoors in a peat-free houseplant compost with added perlite, in bright, indirect light. Water freely and apply a general liquid fertiliser every 2-3 weeks from spring to autumn. Provide high humidity by placing the container on a tray of moist gravel or pebbles. Reduce watering to a minimum in winter, and keep above 15°C. See Alocasia for further advice
Pruning
No pruning required
Propagation
Propagate by sowing seed at 23°C as soon as it's ripe, or by division of rhizomes in spring
Pest resistance
May be susceptible to mealybugs and glasshouse red spider mite
Disease resistance
Generally disease-free