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Alocasia × amazonica
alocasia polly
Garden hybrid registered in Miami in the 1950s; presumed parent species native to Southeast Asia (China, Thailand, Malay Peninsula, Philippines)
Overview
Alocasia × amazonica (commonly sold as 'Alocasia Polly') is a hybrid African mask plant grown almost exclusively as an indoor specimen, reaching 18–24 inches (45–60 cm) tall and 12–18 inches (30–45 cm) wide as a clumping crown. Despite the species epithet 'amazonica', the plant is not from the Amazon and not a wild species; it is a garden hybrid believed to be Alocasia longiloba × Alocasia sanderiana, registered by Salvadore Mauro of Amazon Nursery in Miami in the 1950s. Each leaf is arrowhead-shaped, 8–14 inches (20–35 cm) long and 4–8 inches (10–20 cm) wide, with deeply scalloped wavy margins and prominent silver-white veins running from the leaf tip to the leaf base across a glossy dark green to near-black background; the underside of the leaf is purple. The veins form a contrasting network that reads white-on-black from a distance and gives the plant its 'African mask' common name. The plant grows from a thick rhizomatous corm and produces 4–8 leaves at any one time on a mature specimen, with each leaf lasting 6–12 months before yellowing and being replaced. Cultural failure modes are well-documented: leaf drop from cold air or temperature swings (the species is intolerant of temperatures below 60°F / 16°C), spider mite infestations (dry indoor air below 40 percent humidity), and root rot from soil that stays wet at the base of the pot. Many indoor specimens drop all leaves and enter a temporary dormancy in winter, recovering from the corm with new leaves in spring. All parts contain insoluble calcium oxalate crystals toxic to dogs, cats, and humans on ingestion; ingestion causes oral pain, drooling, and swelling.
Native Range
Alocasia × amazonica is a garden hybrid registered by Salvadore Mauro of Amazon Nursery in Miami in the 1950s and is believed to combine Alocasia longiloba × Alocasia sanderiana as parent species. The parent species are native to Southeast Asia — A. longiloba from southern China through Thailand and the Malay Peninsula, and A. sanderiana from the Philippines.Suggested Uses
Used as a small-to-medium indoor specimen for warm humid bathrooms, kitchens, and humidity-tray-equipped tabletops in containers of 2–3 gallons (8–11 liters). The arrowhead leaves with silver-white veins suit modern interiors as a foliage centerpiece. Combines with smaller foliage houseplants such as Calathea cultivars and Anthurium hybrids for layered tropical indoor plantings. Less suited to households with cats and dogs that browse foliage due to calcium oxalate toxicity, and the plant requires more humidity and warmth than most indoor specimens, so dry low-humidity homes should consider hardier alternatives.How to Identify
Appearance
Size & Dimensions
Height1'6" - 2'
Width/Spread1' - 1'6"
Reaches mature size in approximately 2 years
Colors
Foliage Colors
Fall Foliage Colors
Bloom Information
Flowers occasionally in container culture, producing a 4–6 inch (10–15 cm) greenish-white spathe surrounding a pale spadix; the inflorescence is small and inconspicuous compared with the foliage. Indoor plants are grown for the foliage, which is the year-round display when the plant is not in winter dormancy.
Detailed Descriptions
Flower Description
Greenish-white spathe 4-6 inches (10-15 cm) with pale spadix (occasional in container culture)Foliage Description
Glossy dark green to near-black arrowhead-shaped leaves 8-14 inches (20-35 cm) long with deeply scalloped wavy margins, prominent silver-white veins, and purple undersidesGrowing Conditions
Sun Requirements
Requires 4-6 hours of direct sunlight daily
• Full Sun: 6+ hours of direct sunlight
• Partial Shade: 3-6 hours of direct sunlight
• Full Shade: Less than 3 hours of direct sunlight
Care & Maintenance
Care Guide
Place in bright indirect light at 200–500 foot-candles; direct sun above 4 hours scorches the foliage. Water when the top one-third of the soil volume has dried; the plant prefers consistently moist soil through the active growing season and tolerates drier conditions during winter dormancy. Soil mix should be free-draining and chunky (peat-based potting mix amended with orchid bark and perlite at roughly 50–25–25 percent ratios). Maintain temperatures above 60°F (16°C) at all times and indoor humidity above 50 percent; cold or dry air shows as leaf drop and lower-leaf yellowing. Feed at half the label rate with a balanced liquid fertilizer monthly during active growth (spring through early autumn) and skip feeding in winter. Many specimens drop all leaves in winter and enter dormancy — keep the soil barely moist during dormancy and resume normal watering when new leaves emerge in spring.Pruning
Cut spent yellowing leaves at the base of the petiole with clean scissors. Cut spent flower stalks at the base after bloom finishes. Lift and divide the rhizomatous corm during spring repotting; mature plants produce offset corms that establish quickly in fresh potting mix.Container Growing
Suitable for container growing
Minimum container size: 2 gallons