Anthurium expansum Gleason

• Genus: Anthurium
• Botanical Background: First described by botanist Henry Gleason in the early 20th century, Anthurium expansum has remained a somewhat obscure species in both wild and cultivated settings. It is often studied for its unique floral structure.

• Geographical Range: Native to the high-altitude cloud forests of Costa Rica and Panama
• Environment: Prefers high humidity levels typical of cloud forest ecosystems, Thrives in rich, moist, well-draining soils, often in the shaded forest floor. Cool, consistent temperatures with low seasonal variation, typically ranging between 18°C and 25°C (64°F to 77°F).

Leaves

• Large, glossy, heart-shaped leaves with a slightly corrugated texture
• Leaves are dark green, typically growing 30–40 cm long, and display a subtle, elegant sheen

Inflorescence (Spadix & Spathe)

• Spadix is cylindrical, emerging from a white to pale green spathe that arches around it
• Inflorescence is not particularly fragrant but is visually striking, playing a role in attracting specific pollinators like beetles

Growth Habit

• Terrestrial species, growing from a rhizome and forming a compact, clump-like growth habit. It does not climb or trail but forms a bushy, upright structure

Light Requirements

• Prefers bright, indirect light
• Direct sunlight may scorch its leaves, so filtered light or partial shade is ideal

Watering & Humidity

• Keep the soil evenly moist but not soggy. Allow the top layer to dry slightly between waterings to prevent root rot
• Requires high humidity to thrive, ideally above 60%, and can benefit from misting or a humidity tray

Soil & Potting Mix

• A well-draining, organic-rich potting mix is essential. A mixture of peat, perlite, and pine bark is ideal for maintaining proper moisture levels

Temperature & Fertilizer

• Ideal temperature range is between 18°C and 25°C (64°F to 77°F), with no exposure to cold drafts
• Use a balanced liquid fertilizer once a month during the growing season. Reduce feeding in the winter when the plant is less active

Division

• Propagation is typically done by rhizome division, where healthy sections of the rhizome are separated and potted individually
• Each division should include at least one healthy leaf and root section

Seeds

• Propagation by seed is possible but rarely practiced in cultivation
• Seeds require high humidity and warmth for successful germination, and they may take several months to sprout

Typical Issues

• Spider mites, aphids, and mealybugs
• Fungal infections such as powdery mildew and root rot due to overly wet soil

Treatment Recommendations

• Insecticidal soap or neem oil can effectively control most pests
• A mixture of water and mild dish soap can be used to wash off pests. Ensure good air circulation and avoid overhead watering to minimize fungal diseases

• Notable for its rarity in both the wild and cultivation, making it highly sought after by aroid collectors
• Excellent example of an aroid adapted to cooler, shaded environments

• Large, glossy leaves and unique spadix make it a prized ornamental specimen
• Its rarity and dramatic foliage add significant value to any collection

Wild Population Status

• Not currently listed as endangered
• Limited range and specialized habitat make it vulnerable to habitat loss due to deforestation in Central America

Market Availability

• Rare in commercial markets, and plants are generally only found in specialty nurseries or through private collectors
• Not widely cultivated, adding to its appeal among aroid enthusiasts