Alocasia atropurpurea Engl.

• Genus: Alocasia
• Botanical Background: First described by Adolf Engler in Das Pflanzenreich (1920) based on a 1913 Mount Polis specimen

• Geographical Range: Endemic to the wet tropical forests of northern Luzon, Philippines, with additional wild populations in the Ryukyu (Nansei‑shoto) islands
• Environment: Thrives in shaded understory of moist tropical forests with high humidity (>70%), well‑drained, humus‑rich soils, and stable temperatures around 20–28 °C

Leaves

• Large
• Glossy green
• Heart‑ to arrow‑shaped blades
• Prominent venation

Inflorescence (Spadix & Spathe)

• Typical aroid inflorescence
• Spathe limb deep purple‑brown (~14 cm), lower spathe ~4 cm; spadix slightly shorter
• Fly‑pollinated via sapromyophilous cues

Growth Habit

• Terrestrial subshrub arising from a thick rhizome, forming compact clumps; non‑climbing habit

Light Requirements

• Bright, indirect light; avoid direct sun to prevent leaf scorch

Watering & Humidity

• Keep substrate evenly moist but never waterlogged
• Humidity 60–80%, achieved via misting, pebble trays, or humidifiers

Soil & Potting Mix

• A chunky, well‑draining mix rich in organic matter (e.g., coco coir, orchid bark, perlite)
• Use unglazed pots to moderate moisture

Temperature & Fertilizer

• Ideal range 18–28 °C
• Feed monthly in spring/summer with half‑strength balanced fertilizer; reduce feeding in autumn/winter

Division and Cuttings

• Separate offsets or rhizome sections during repotting

Seeds

• Declines rapidly once berries are removed; sow fresh within hours; rinse pulp, keep moist in paper towel, sow in sterile, well‑draining medium at ~25 °C

Typical Issues

• Aphids, spider mites, mealybugs
• Root rot from overwatering
• Fungal leaf spots in high humidity without air

Treatment Recommendations

• Neem oil or insecticidal soap sprays; ensure good ventilation
• Systemic miticides or insect growth regulators for severe infestations
• Treat root rot with fungicides and repotting in fresh mix

• Critically endangered due to habitat loss and limited wild range
• Specific epithet atropurpurea highlights its unique spathe color

• Prized for its striking deep‑purple inflorescence and sculptural foliage
• Features prominently in aroid specialist collections

Wild Population Status

• Listed as Critically Endangered (IUCN 2008) with very few known wild occurrences

Market Availability

• Rare in general trade; most specimens are propagated via tissue culture by specialist nurseries to reduce wild collection