Bulb · Araceae
Elephant Ear
Colocasia esculenta
Feed it rich soil, full sun, and water it can never run dry, and elephant ear unfurls vast heart-shaped leaves all season.
Full sun
45–86°F · 7–30°C
USDA 8–11
3–6 ft · 0.9–1.8 m
Overview
The leaves are what stop you. Broad and heart-shaped, they widen past 3 feet (91 cm) across and hang from long, upright stalks, their surfaces stretched thin enough that light glows through them at the edges. Each blade arches from the corm below, the swollen underground stem the kitchen knows as taro, and the plant counts among the arums.
Up close the foliage reads as soft and pliant, the kind that ripples and bends in a breeze rather than holding stiff. In its hardy range of zones 8 to 11 fresh blades push up year after year, and in cooler ground the corm waits out winter to send them again. The same supple leaves sit easily over shallow standing water at a pond margin, their long stalks lifting them clear of the surface.
The clump builds quickly into a thicket of overlapping green sails, each new leaf rising taller than the last. Constant moisture and feeding keep the blades wide and unblemished, and shelter from wind keeps them whole. Handle them sparingly, though: every raw part is toxic, packed with stinging crystals just under the surface.
Care
The short version: the soil stays rich and constantly wet so it never dries, the light runs from full sun to part shade, the air stays warm, a balanced feed comes monthly through spring and summer, and the corms come up before frost where the plant is not hardy.
Light
In full sun the blades reach their fullest size and deepest color, and they still hold up in part sun or part shade, just smaller. Under hard summer sun the thin leaf edges scorch and brown, so afternoon shade keeps the surfaces whole and unmarked.
Water
The wide, thin leaves lose water fast, so the plant wants constantly wet, boggy soil and should never dry out, and it will stand as a pond marginal in up to 6 inches of standing water. The more sun and heat strike those broad surfaces, the more water the roots must pull up.
Soil
The roots sit in fertile, humus-rich clay or loam that stays moist, dark spongy ground that most plants would find too wet. The plant takes the occasional flood in stride, which lets the long stalks rise straight from the waterline at a pond edge.
Temperature
The foliage stays lush from about 45°F to 86°F (7°C to 30°C), and growth slows and the leaves stiffen as the air cools. There is no frost tolerance in the soft tissue, so the first freeze collapses the blades and ends the season above ground.
Humidity
Drawn from steamy tropical ground, the plant wants high humidity, and damp air keeps the broad leaf margins from drying and curling. That same need for moist air is why the foliage looks freshest near water.
Feeding
Through spring and summer, while new blades keep unrolling, a balanced fertilizer goes on once a month. Rich soil and steady feeding are what push each leaf to its oversized width.
Pruning
Little is needed beyond clearing spent foliage. Tattered, yellowing, or frost-damaged leaves come off as they fade, and shelter from strong wind keeps gusts from shredding the large, soft blades.
Repotting
The corms are divided and repotted in spring as the clump swells. Crowded corms, shrinking leaves, or a clump pushing up out of the pot show on the surface when it is time to split.
Size & spacing
A full clump stands 3 to 6 feet (91 to 183 cm) tall and spreads as wide, the blades overlapping into a solid mass of green. Spacing gives each leaf room to open flat without pressing against the next.
When to plant
Elephant ear lives on warmth and blackens at frost. The pale corms go into the ground in mid-spring once the soil has warmed and the cold has passed, the first furled leaves unroll through the warm months into broad blades, and the corms come back up before the first fall frost where the plant is not hardy.
Northern hemisphere
Southern hemisphere
Typical months for a temperate climate: start earlier in warm zones, later where spring frosts linger.
- Plant: Plant corms in mid-spring after the soil warms and frost danger has passed
- Harvest: Rarely flowers in cultivation (yellowish-white spathe); grown as a foliage plant
Hardiness
USDA hardiness zones: 8–11
Temperature: down to -12°C
Troubleshooting
Elephant ear stays nearly pest-free, so its troubles show on the leaves themselves, usually from dryness or cold. A scorched margin or a blackened blade tells the story at a glance. Match the look below before more of the foliage gives way.
Browning, scorched leaf edges and wilting leaves
Crisp brown margins and slack, drooping blades mark a bog plant gone dry. Elephant ear wants wet soil at all times, and full hot sun pulls water from the broad surfaces faster than dry roots can replace it, so the thin edges burn first. Deep watering, a layer of mulch, and afternoon shade in harsh summers bring the leaves back firm.
Fix:
- Water deeply and keep soil consistently wet
- Mulch to retain moisture
- Provide afternoon shade in hot climates
Leaves collapse and turn black after a cold night
Limp, blackened blades that fold over signal frost damage, the result of freezing air rupturing the soft tissue. The first fall frost darkens the whole canopy overnight. The ruined leaves come off, and the corms go into storage somewhere cool and dry above 45°F (7°C) until spring.
Fix:
- Cut back damaged foliage
- Dig corms after first frost and overwinter in a cool, dry place above 45°F
Toxicity
Just beneath the smooth surface of every leaf, stem, and corm sit insoluble calcium oxalate crystals, packed in needle-fine bundles. Chewed, they drive into the soft tissue and sting and swell the mouth and throat at once, and the swelling can be serious. The same crystals make the raw plant toxic to cats, dogs, horses, and people, and only thorough cooking of the corm yields edible taro, so keep the raw plant away from pets, livestock, and children.
Toxic to
Cats · Dogs · Horses · Rabbits · Livestock · Birds · People
Cats Moderate
A cat that bites into a blade meets the crystals at once and feels a fast, painful sting in the mouth, followed by heavy drooling, pawing at the face, a swollen mouth and tongue, vomiting, and trouble swallowing.
Dogs Moderate
The crystals burn a dog's mouth the moment the leaf is bitten, so most drop it fast, with drooling, retching, a swollen tongue, and difficulty swallowing soon after.
Horses Moderate
A grazing horse takes the same searing across the mouth and lips, the tissue drooling and swelling until the animal turns away from feed.
Rabbits Toxic
The needle-like raphides irritate a rabbit's small mouth and gut with little margin to spare, so the plant belongs well out of any rabbit's reach.
Livestock Toxic
Cattle, goats, and sheep that browse the raw blades take painful swelling through the mouth and digestive upset, and they may refuse feed while the raw tissue heals.
Birds Toxic
A bird that nibbles a leaf takes the same caustic burn across the mouth and crop, so the whole raw plant is off limits to it.
People Caution
Raw, every part stings the mouth and throat and can swell the airway, so no part of the fresh plant is a green to eat. The corm becomes edible taro only after thorough cooking in salted water, where heat breaks the crystals down; cooked it is safe, raw it is not.
Wear gloves when dividing corms; plant sap and raphides can irritate skin and mucous membranes.
Helpline numbers
United States
ASPCA Animal Poison Control: (888) 426-4435 (fee applies)
Poison Control: (800) 222-1222
Canada
Poison Centres: 1-844-764-7669
Varieties
The elephant ears gardeners reach for are picked for the color and finish of the leaf itself, most of them deep and dark. The selections below are the ones whose foliage is easiest to tell apart.
'Black Magic'
Its blades are a dusky purple-black, carried on stems of the same dark shade for an almost charcoal cast across the leaf.
'Illustris'
Its dark, near-black blades are laced with bright green veins that trace sharp lines against the deep ground color.
'Black Coral'
Its foliage is glossy and ruffled along the edges, a deep blue-black that throws back the light off its surface.
'Mojito'
Its green blades are flecked and splashed at random with dark purple-black, so the markings differ from leaf to leaf.
How to propagate
New plants come straight from the corms, the same plump underground stems the clump already makes. Splitting a clump puts those corms to work for you.
DivisionEasy
Spring, as new growth begins · A few weeks to establish in warm, moist conditions
A clump splits apart in spring as the first new growth shows. The pale corms pull free of one another and go into a rich, peaty mix kept constantly moist. In warm conditions fresh roots and shoots take hold within a few weeks.
Bulbs & cormsEasy
Plant corms in mid-spring after frost · Sprouts and establishes over several weeks once soil is warm
Stored corms also go into the ground in mid-spring, once frost has passed and the soil is warm, then push roots and a first shoot over several weeks. In zones colder than its hardy range, the corms lift out each fall and overwinter above 45°F (7°C).
Myths
Elephant ear and taro are poisonous, so they can never be eaten.
Raw, the plant is toxic, since the insoluble calcium oxalate raphides packed in its tissue burn the mouth. The corm itself is a staple across the tropics and the taro behind Hawaiian poi, once it has cooked through in salted water. Cooking breaks down the crystals and makes it safe; raw, it stays poisonous.