Repotting guide

When & how to repot Colocasia Antiquorum (Colocasia antiquorum)

Also called dasheen, old-world taro.

More about colocasia antiquorum

About Colocasia Antiquorum

Colocasia antiquorum · also called dasheen, old-world taro · edible

Colocasia antiquorum, the old-world dasheen taro, is a heat-loving aroid grown for its starchy corms and downward-pointing peltate leaves. It thrives in warm, swampy, fertile ground with constant moisture and high humidity, growing fast in a single season. All raw parts contain calcium oxalate and must be thoroughly cooked before eating.

Mature size: 0.9-1.5 m tall with a similar spread in one season; leaves up to 60 cm long.

How to tell colocasia antiquorum needs repotting

Repotting on a calendar is less reliable than reading the plant. For colocasia antiquorum, watch for these signs:

Flowering has tailed off year on year and the clump has become congested and overcrowded.
Lots of leaf and few flowers — a classic sign that colocasia antiquorum bulbs or tubers need lifting and dividing.
Bulbs visibly bursting the pot or pushing each other to the surface.
It is the natural dormancy window (foliage yellowed and died back) — the only safe time to lift and split.

For the underlying biology of a pot-bound root system and why it stalls a plant, see our guide to spotting and fixing a root-bound plant.

How often to repot colocasia antiquorum

Lift and divide every 3–4 years once clumps congest. Rather than a true repot, colocasia antiquorum is lifted and divided once the clump congests and flowering drops off. Clumping herbaceous perennial growing from a central corm with downward-pointing (peltate) heart-shaped leaves on succulent stalks; spreads by offset cormels..

What size pot to step colocasia antiquorum up to

Pot size matters less than depth and spacing here. When you replant colocasia antiquorum, set the bulbs or tubers at the correct depth (a rough guide: two to three times their own height of soil over the top) and space them so they are not touching. A wide, shallow pot suits a clump better than a tall narrow one.

Not sure of the exact diameter? Our pot size calculator takes the current pot and root spread and tells you the right next size — it deliberately recommends a single step up, never a big jump.

The best time of year to repot colocasia antiquorum

The only safe window is dormancy: wait until the foliage has yellowed and died back naturally, lift and divide then, and replant before or at the start of the next growing season. Disturbing colocasia antiquorum in full growth or flower sets it back badly.

Step-by-step: repotting colocasia antiquorum

Wait for dormancy. Let colocasia antiquorum foliage yellow and die back completely. Lifting while it is in growth wastes the energy it is storing for next year.
Lift carefully. Loosen the soil well away from the bulbs/tubers with a fork and ease the whole clump out without spearing them.
Separate the offsets. Gently pull the clump apart into individual bulbs or tubers. Keep only firm, healthy, blemish-free ones.
Replant at the right depth. Reset them in fresh rich, heavy, water-retentive loam to clay loam at the correct depth and spacing — not touching — so each has room to bulk up.
Water in and rest. Water once to settle them, then keep on the dry side until growth resumes. Do not feed until leaves are actively growing.

Aftercare

After replanting colocasia antiquorum, keep the soil barely moist — not wet — until shoots appear; bulbs and tubers rot in cold, saturated soil. Once leaves are growing strongly, resume normal watering. Hold off feeding until the plant is in active growth again.

The right soil mix for colocasia antiquorum

Colocasia Antiquorum wants rich, heavy, water-retentive loam to clay loam. Wants deep, fertile, humus-rich ground that holds water. Amend generously with compost or rotted manure; a slightly acidic to neutral pH around 5.5-6.5 suits corm development. Always use fresh mix when you repot — reusing old, broken-down soil reintroduces the compaction and poor drainage you are repotting to fix.

Repotting colocasia antiquorum — frequently asked questions

How often should you repot colocasia antiquorum?

Lift and divide every 3–4 years once clumps congest for colocasia antiquorum. Colocasia Antiquorum is lifted and divided, not "repotted". Every 3–4 years, once the foliage has died back and it is dormant, lift the clump, separate the offsets, and replant at the correct depth in rich, heavy, water-retentive loam to clay loam. Crowding, not pot size, is what reduces flowering over time.

What size pot does colocasia antiquorum need?

When is the best time of year to repot colocasia antiquorum?

Do you "repot" colocasia antiquorum, or lift and divide it?

You lift and divide it. Colocasia Antiquorum grows from bulbs or tubers, so instead of repotting you wait for dormancy, lift the congested clump, separate the healthy offsets, and replant them at the right depth and spacing. Doing this every 3–4 years restores flowering.

Should you fertilise colocasia antiquorum after repotting?

Hold off feeding colocasia antiquorum until it is in active growth again. Fresh soil already carries enough nutrients to get it re-established, and feeding disturbed roots too soon does more harm than good.