Plant care guide

Alocasia Propagation: Divide Pups and Pot Up Corms

Updated

What should you know about corm pup propagation for an Alocasia?

Alocasia is propagated by division, not by leaf or stem cuttings. Separate offsets (pups) that have their own roots, divide the fleshy rhizome, or pot up the small corms found in the root ball.

What to do first

In spring, unpot the plant, cut away pups with as much root as possible, and pot each one in gritty, well-drained mix. Pot loose corms the same way and keep everything warm, above 16 °C (60 °F), in bright indirect light.

Alocasia does not root from a cut leaf. New plants come from the underground parts. NC State Extension gives division of offsets as the way to propagate Alocasia. The RHS Alocasia growing guide calls separating offsets the easiest method. It also describes dividing the fleshy rhizome.

You have three kinds of material to work with:

  • Pups (offsets). Small plants that sprout around the base of a mature Alocasia, each with its own leaves.
  • Rhizome pieces. Sections cut from the thick underground stem of a clump.
  • Corms. Small, firm, rounded storage organs that often turn up in the mix during repotting. NC State notes that corms may be started indoors in pots.

When to propagate

The RHS recommends separating offsets in spring and dividing the rhizome in late spring or early summer. This is when Alocasia comes out of its cooler, drier winter rest. Iowa State University Extension’s division guide calls early spring the ideal time for most houseplant division.

Do not divide a plant that is collapsing or rotting. Sort out the root problem first, and divide once the plant is growing again.

Before you start

  • Wear gloves. The RHS warns that Alocasia sap can irritate skin. The ASPCA lists Alocasia as toxic to dogs, cats and horses, so keep offcuts away from pets.
  • Clean a sharp knife.
  • Prepare small pots with drainage holes. The RHS suggests a peat-free multipurpose compost with horticultural grit added, about three parts compost to one part grit.

Divide pups (offsets)

  1. Slide the plant out of its pot. Lay it on its side and loosen the mix with your fingers, as Iowa State describes.
  2. Find where each pup joins the parent. The RHS advises slicing down with a knife and taking as much root as possible with the pup.
  3. Keep only pups with healthy leaves and roots. Iowa State notes that larger pieces recover more quickly.
  4. Pot each pup on its own in fresh mix, at the depth it grew before. Use a pot sized to its roots, not a large one.
  5. Water once to settle the mix and let it drain fully.
  6. Place the pots in bright, indirect light. Iowa State recommends waiting a few weeks before fertilizing so roots can recover.

Divide the rhizome

A large, crowded clump can be split into pieces. The RHS says to divide the fleshy rhizome in late spring or early summer and pot up the pieces. Give each piece at least one growing point and some roots. Pot them in gritty mix and keep them warm and in good light. The RHS notes they should soon produce new shoots.

Pot up loose corms

Corms that fall out of the root ball can grow into new plants. NC State notes that corms may be started indoors in pots. Missouri Botanical Garden’s Alocasia group page says the same of rhizomes and tuberous roots.

  1. Keep only firm corms. Discard any that are soft, hollow or smell rotten.
  2. Pot each corm in moist, well-drained mix, with the pointed growing end up and the top near the surface.
  3. Keep the mix lightly moist, never waterlogged. The RHS warns that overwatering can rot Alocasia roots.
  4. Keep the pot warm. The RHS says Alocasia needs at least 16 °C (60 °F) during the growing season.
  5. Wait for a shoot before you increase watering.

Aftercare for new divisions

  • Warmth. NC State reports that Alocasia grows best where daytime temperatures are 20–25 °C (68–77 °F). Keep new pots away from cold drafts.
  • Light. The RHS recommends bright but indirect light. Strong sun can scorch leaves.
  • Water. Once the plants are growing, the RHS suggests watering when the top 5 cm (2 in) of mix is dry.
  • Feeding. Hold fertilizer until new leaves appear.
  • Leaf loss. Clemson HGIC’s houseplant disorders guide notes that some leaf drop follows a big change in environment. Check the base and roots if leaves keep collapsing.

Store corms over winter (garden-grown elephant ears)

Alocasia grown outdoors in cold climates is lifted before frost. NC State notes that tubers can be removed from the soil and stored in a cool, dry place over winter. Clemson HGIC’s elephant ear article describes cutting back the foliage, drying the corms for several days, and storing them in an open container lightly covered with dry peat moss. Clemson gives 7–13 °C (45–55 °F) as the ideal storage range and warns not to let corms freeze. Replant them in spring after the last frost.

Missouri Botanical Garden adds that rhizomatous Alocasias are best left in their pots all year. Lift only tuberous types.

For more on waking stored or resting plants, see how to wake up an Alocasia after dormancy. The Alocasia care guide covers watering and corm checks, and the Alocasia hub lists our other Alocasia pages.

Other alocasia problems we cover: humidity requirements, brown spots, root rot, brown tips, overwatering.

References

How this guide was put together: RHS, NC State Extension, Missouri Botanical Garden, Iowa State University Extension, Clemson HGIC, and ASPCA guidance.

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Knowledge record: GR-0096