Alocasia Corms: Harvest, Wake, and Grow Your Own Backup

Alocasia are the only plants in our studio that ship with their own insurance. Along the rhizome and among the roots, a healthy plant builds corms: small, hard, brown-husked bulbs the size of a chickpea to a hazelnut. Each one is a complete plant waiting for a signal. Most growers throw them away with the old substrate. That is a rare plant going into the bin. When to look: at every repot, and whenever a plant is unpotted for root inspection. Gently work the substrate off the root ball and feel along the rhizome. Corms detach with a light twist; if one resists, leave it, it is still feeding. Peel or not: under the brown papery husk is a smooth, pale corm with a pointed growing tip. Peeling the husk off speeds sprouting by weeks and lets you see rot early. Use your fingernail, work from the base toward the tip, and never nick the tip itself. A corm that is soft, hollow or smells sour is dead; discard it. Waking them: a closed, clear container with a lid. Base of damp (not wet) sphagnum moss, corms set tip-up half buried, lid closed. Alternatively LECA with water sitting just below the corms so they draw moisture without touching it. Conditions: 25 to 28°C, bright indirect light, humidity near 90% inside the box. On top of a router or a warm cabinet shelf works. Open the lid for a minute every two days to exchange air. Timeline: roots in one to three weeks, first leaf in three to six weeks. Some corms take three months. Patience is the whole technique. Potting up: when a corm has two roots longer than three centimeters and a first leaf, move it into a small pot of Fluval Stratum or fine bark mix, and keep it in high humidity for another month before it meets the room. This is a TC start in every way that matters; treat it with the 21-day hardening SOP. Variegation: a corm from a variegated Alocasia is not a guaranteed variegated plant. Variegation is a chimera in the growing point; each corm carries its own copy of it, or does not. Expect a mix: some fully variegated, some green, some in between. A green sprout from a pink or white plant is normal, and a fully variegated corm plant is the reason this is worth doing. Storage: dry corms keep for months in a paper bag of barely damp coir at room temperature. Check monthly and discard anything soft.