Elephant Ear
Colocasia esculenta · Taro
It grows in warm, wet ground across tropical Asia, throwing up huge heart-shaped leaves on stout stalks from an underground corm. That corm is taro, one of the oldest food crops on Earth, and the same plant you can buy for a few dollars as a giant-leaved patio tropical.
Family
Araceae
Origin
Tropical Asia
In the wild
Marsh and paddy
Indoors
0.9–1.8 m
Growth
Fast
With pets
Toxic
Where it's from
Southern India and Southeast Asia
Wetland country
Marsh margins, stream banks and flooded paddies across warm tropical Asia, grown both flooded and dryland.
Outdoors: zones 8–10
Frost kills the foliage. Colder than zone 8, the corm is lifted and stored over winter.
Invasive on the Gulf Coast
Naturalised and weedy in southeastern US wetlands, where it displaces native marsh plants. Plant responsibly near waterways.
The oldest food crop
This is taro, the corm that feeds more than 100 million people and the starch behind Hawaiian poi. Independently domesticated several times across the Pacific and Asia, it carries an estimated 15,000 food varieties. But it must be cooked: raw taro holds the same irritant crystals that make the ornamental toxic.
Cooked, not raw
Thorough cooking or soaking breaks down the calcium oxalate crystals that make it harmful raw.
Down means Colocasia
If the giant leaves point down it is a Colocasia. If they point up it is an Alocasia.
Grown for the leaf or the corm
It rarely flowers in cultivation, and the bloom is insignificant. It is kept for foliage or food.
How to keep it
LightFull sun to part shade
Wants a lot of light. Indoors, give it the brightest spot you have.
WaterKeep wet
A bog plant. Keep the soil constantly moist to wet, even standing water. Do not let it dry out.
HumidityHighA tropical wetland plant. Dry air browns the leaf edges.
TemperatureAbove 10°CFrost-tender. Foliage dies back at the first frost. Store dormant corms cool and dry in cold zones.
SoilRich, moisture-retentiveFertile, humus-rich soil that holds water. It likes wet, boggy conditions.
FeedingHeavy in growthA heavy feeder. Regular feeding through the growing season supports the large leaves.
DifficultyEasy to moderateVigorous and forgiving in warmth and moisture. Often grown as a summer plant and overwintered as a corm.
With petsToxicInsoluble calcium oxalate crystals. Oral burning, drooling, vomiting and difficulty swallowing if chewed.
PropagationCorm divisionLift and split the corm or separate offset cormels in spring. Not from stem cuttings.
RepottingEvery 1–2 yearsVigorous. It fills a pot quickly, so pot up or divide regularly.
What the data says
What it costs
A mass-market patio and pond plant, and a global food crop sold as produce.
$5–25
Dark named cultivars like Black Coral, Mojito and the Royal Hawaiian series run a little higher. There is no speculative tier.
IUCN · Least Concern
In the wild
The inversion of the usual houseplant tragedy: too successful, not endangered.
A domesticated staple humans have carried, planted and eaten for thousands of years, assessed Least Concern. The conservation concern runs the other way: it has become an invasive weed in places it was never native, choking Gulf-Coast wetlands. Not vanishing in the wild, taking over it.
When it sulks
Wilting, drooping leavesThe number one issue. This is a wetland plant. Keep it wet.
Brown crispy leaf edgesLow humidity, dry air or inconsistent moisture.
Yellowing and collapse in autumnFrost or cold. Normal dieback. Lift and store the corm in cold zones.
Leaf scorchSudden full sun on a plant that was not acclimated to it.
Unwanted spread outdoorsIt naturalises aggressively in warm wet ground. Keep it away from natural waterways.
Varieties & company
The varieties
Black MagicIllustrisMojitoBlack CoralPink China
Pairs with · keep apart from
CannaBananaCaladiumSnake PlantCactiSucculents
A new plant, every week.
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