The Alocasia ‘Polly’, commonly known as the African Mask Plant, is a captivating houseplant prized for its dramatic, arrow-shaped foliage featuring deep green color and prominent, silvery-white veins. This striking hybrid cultivar has become highly sought after by houseplant enthusiasts looking to add an exotic, tropical flair to their indoor spaces. Successfully multiplying your collection is an achievable goal. The primary method for creating new ‘Polly’ plants involves harvesting and sprouting the small, potato-like structures known as corms. This guide provides the necessary steps to successfully propagate your plant using these tiny underground energy stores.
Essential Preparation and Timing
The timing of propagation significantly influences the success rate of sprouting corms. Alocasia plants are tropical perennials that thrive during the warmer, brighter months, making spring and early summer the most advantageous seasons for propagation. Attempting to harvest corms during the fall or winter may result in a much slower process, as the plant’s natural tendency is to enter a period of dormancy when light levels and temperatures drop.
Before starting, gather all materials to ensure a smooth transition for the corms. You will need a clean, sharp cutting tool, such as sterilized scissors or a knife, to cleanly detach the corms from the parent plant. Prepare a propagation vessel and a suitable growing medium, which should be moisture-retentive but airy, like perlite, sphagnum moss, or an aroid soil mix. Finally, select a healthy, mature parent plant, as younger specimens may not have produced viable corms yet.
Step-by-Step Corm Propagation
The propagation process begins with carefully removing the mature Alocasia ‘Polly’ from its pot to access the root system. Gently shake or brush away the excess soil from the root ball to expose the rhizome and its network of roots. The corms are small, round, brown structures, often found attached to the main rhizome or scattered loosely in the soil.
Once the corms are located, use your sterilized cutting tool to snip them away from the parent plant’s roots with a clean cut. You should only detach corms that are firm to the touch; discard any that feel squishy or soft, as they have likely rotted. While optional, gently peel the outer brown, papery layer, known as the tunic, which may speed up the initial sprouting process by allowing moisture to penetrate more easily.
The prepared corms are then ready to be placed in the chosen propagation medium. If using sphagnum moss or perlite, ensure the medium is pre-moistened but not waterlogged. The corm should be oriented with the small, slightly pointed end facing upward, as this is the growth point where the new leaf will emerge. Alternatively, corms can be placed in a shallow container of water, ensuring they are only partially submerged to prevent rot.
Post-Propagation Care for Success
After planting the corms, the focus shifts to creating an environment that encourages rapid rooting and sprouting. The primary factor for successful corm propagation is maintaining high ambient humidity, ideally close to 100 percent. This can be achieved by placing the propagation vessel inside a clear, sealed container, a dedicated humidity dome, or even a simple plastic bag to trap moisture.
The corms should be placed in a warm location that receives bright, indirect light. While the corms themselves do not require light to sprout roots, the warmth is necessary. The developing plantlets will quickly need light for photosynthesis once they emerge. The preferred temperature range for growth is between 65°F and 75°F (18°C to 24°C), mimicking their native tropical habitat.
Be prepared for a waiting period, as corm propagation requires patience. Roots can begin to form in a few weeks, but the first tiny leaf may take anywhere from one to two months to appear.
Hardening Off and Transplanting
Once the plantlet has developed strong roots and at least one fully formed leaf, it is time to transition it out of the high-humidity environment. This process, known as hardening off, involves gradually exposing the plant to the lower humidity of your home over a few days or weeks, which prevents shock and leaf desiccation. The new plant can then be transplanted into a small pot filled with a chunky, well-draining aroid mix.