Bulb · Araceae
Caladium
Caladium bicolor
Give it warm soil, dappled shade, and steady moisture, and the caladium throws up heart-shaped leaves splashed in red, pink, and white.
Partial shade
Every 2–4 days
61–86°F · 16–30°C
60–90 days
Overview
Caladiums are grown for their leaves, not their flowers. Each tuber pushes up big, paper-thin, heart-shaped foliage marbled in red, pink, white, and green, and a single plant can light up a shady corner where little else has much color. The plant belongs to the arum family, the same group as philodendrons and peace lilies, and it carries that family's love of warmth and humidity.
This is a tropical tuber, so it lives by the warmth. It wakes up, grows fast, and reaches full size in one season, then dies back and rests as the weather cools. You can grow it in a shaded bed, a patio pot, or indoors as a houseplant, but in every case it wants warm soil and air around 16°C and up before it will do anything at all.
Color is the whole point, and shade is what protects it. Strong sun bleaches the bright markings toward plain green and scorches the delicate leaves, while dappled light keeps them vivid. Caladiums are not difficult once the warmth is there, but they are particular about that one thing.
Care
The short version: partial to dappled shade, warm soil that never drops cold, and even moisture through the growing season. Feed lightly, keep the humidity up, and ease off the water as the leaves yellow into dormancy.
Light
Partial to dappled shade is the sweet spot, with maybe 2 to 4 hours of gentle sun and shelter from hot afternoon light. Too much direct sun fades the bright markings to green and scorches the thin leaves, while deep shade keeps the color richest.
Water
Caladiums are thirsty in active growth, so keep the soil evenly moist to the touch but never waterlogged, since soggy ground rots the tubers. Watering every 2 to 4 days suits most plants, and you ease right off as the leaves yellow toward dormancy.
Soil
Plant in fertile, well-drained soil loaded with organic matter so it holds moisture without staying wet. A slightly acidic pH of 5.5 to 6.0 suits them, and good drainage is what keeps tuber rot at bay.
Temperature
Warmth is everything here. Caladiums grow between 61°F and 86°F (16°C to 30°C) and sulk or stall in anything cooler, so wait for the soil to warm before the tubers go out.
Humidity
These are tropical plants that want humidity of 60% or more. Dry indoor air leaves the leaf edges crisp and brown, so group plants together, set them over a pebble tray, or run a humidifier in a dry room.
Feeding
Feed every two weeks through the growing season with a balanced liquid fertilizer, or use a slow-release low-phosphorus formula instead. Go easy, because over-feeding fades the reds and whites toward plain green.
Pruning
There is little to prune. Snip off yellowing or damaged leaves at the base, and removing the central bud on a tuber before planting pushes it to throw more shoots and leaves.
Repotting
Caladiums are replanted each year from stored tubers rather than potted on. Leave established clumps undisturbed, and lift and divide only when the tubers crowd and lift at the surface or the leaves shrink over the season.
Size & spacing
A caladium grows 12 to 30 inches (30 to 76 cm) tall with a matching spread. Set tubers 8 to 12 inches apart so the broad leaves have room to fill in without crowding.
When to plant
Caladiums run on warmth, not the calendar. Start tubers indoors a few weeks before the last frost if you want a head start, then move them out only once the soil has warmed through in late spring. They fill out over summer and die back as the season cools.
Northern hemisphere
Southern hemisphere
Typical months for a temperate climate: start earlier in warm zones, later where spring frosts linger.
- Sow: Start tubers indoors 4-6 weeks before the last frost in a warm spot, keeping the medium about 70 degrees F, to get a head start in cold-winter regions
- Plant: After all danger of frost has passed and soil reaches at least 60-70 degrees F (late spring to early summer)
- Harvest: Grown for foliage, which reaches full size in one season; insignificant arum-type spathe flowers may appear in summer
Hardiness
USDA hardiness zones: 9–10
Temperature: down to -7°C
Troubleshooting
Caladium trouble usually shows up in two places: tubers that won't wake in cold ground, and leaves that lose their color or get chewed. Read the early signs and most of it is easy to head off. Match what you see below, then act before the season runs out.
Tubers that sit in the ground and rot instead of sprouting
Cold, wet soil is almost always the reason caladium tubers stall or rot before they ever break the surface. Wait until the ground holds steady at 60°F to 70°F (16°C to 21°C), improve drainage so the soil stays moist but never soggy, and toss any tuber that already feels soft. Starting with clean, disease-free stock keeps fungal tuber rot out of the bed in the first place.
Fix:
- Wait to plant until soil is consistently 60-70 degrees F
- Improve drainage and reduce watering so soil is moist but not saturated
- Discard soft or rotted tubers and start with disease-free stock
Leaves losing their red, pink, or white and turning plain green
When the bright markings wash out toward green, the plant is usually getting too much direct sun or too much fertilizer. Move it into partial or dappled shade away from hot afternoon light, and cut feeding back to a light touch once or twice a season. Shade is what keeps the color rich, so the deeper the dapple, the bolder the leaves.
Fix:
- Move to partial or dappled shade with protection from hot afternoon sun
- Reduce fertilizer to a light application once or twice in the season
Ragged holes and chewed edges across the leaves
Most chewed caladium foliage is the work of slugs and snails, which feed after dark and leave shiny slime trails behind them. Hand-pick them at night or set out bait, and clear away the damp hiding spots they shelter in. Torn rather than chewed leaves point instead to wind or hail battering the brittle foliage, so a sheltered spot helps.
Fix:
- Hand-pick slugs and snails or use baits per label
- Site out of strong wind to protect brittle leaves
Toxicity
Every part of a caladium is toxic, with no exception. The leaves, stems, and tubers are packed with insoluble calcium oxalate crystals that act like microscopic needles, and a single bite sets off intense burning, drooling, and swelling of the mouth and throat. No part is edible, so keep the plant and any stored tubers away from pets, livestock, and children.
Toxic to
Cats · Dogs · Horses · Rabbits · Livestock · Birds · People
Cats Toxic
A cat that bites a leaf feels the burn at once, pawing at its mouth and drooling hard. The lips, tongue, and throat swell, and vomiting and trouble swallowing often follow.
Dogs Toxic
Dogs that chew any part get a sharp sting in the mouth, with heavy drooling and a swollen tongue. Most back off fast, but vomiting and a refusal to eat can linger for a day.
Horses Toxic
The crystals inflame a horse's mouth and lips on contact, bringing pain, drooling, and difficulty swallowing. Horses cannot vomit, so the irritation stays where the plant was bitten.
Rabbits Toxic
Rabbits face the same needle-like crystals, which scald the mouth and gut and put them off their food. Keep the plant and any stored tubers well out of their reach.
Livestock Toxic
Grazing animals like goats, sheep, and cattle suffer mouth and gut irritation if they sample the foliage. Most spit it out quickly because the burn is immediate, but keep the plants away from pasture.
Birds Toxic
The oxalate raphides irritate a bird's mouth and crop just as they do in mammals, so pet birds should never have access to the leaves or sap.
People Caution
No part of the plant is edible. A bite brings instant burning of the lips and mouth, drooling, and swelling, and the sap can leave skin itchy, so wash your hands after handling and keep it away from children.
Keep plants and stored tubers out of reach of pets and children; wash hands after handling sap.
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
Caladiums come in hundreds of named selections, sorted mainly by leaf shape. A few stand out as the ones worth knowing.
Candidum
A classic fancy-leaved selection prized for its near-white leaves laced with bold green veins.
Pink Cloud
A named fancy-leaved cultivar listed by NC State, carrying soft pink-flushed foliage.
Lance-leaved (strap-leaved) types
These stay narrower and generally under 12 inches tall, and they take more sun than the fancy-leaved kinds.
How to propagate
Caladiums multiply through their tubers, and you can do it by cutting them up or by splitting off the offsets a clump makes on its own.
DivisionEasy
Late winter to early spring before planting, while tubers are dormant · 4-6 weeks to sprout in warm soil; full size in one season
Divide tubers in late winter or early spring while they are dormant. Cut a large tuber into pieces, each carrying at least one eye, let the cut faces dry and callus over, then plant them eye-side up about 2 inches deep. In warm soil the pieces sprout in 4 to 6 weeks and fill out to full size within the one season.
Offsets & pupsEasy
At lifting in autumn or replanting in spring · One growing season to reach mature size
Caladiums also build their own daughter tubers around the parent. Lift the clump in autumn or at replanting in spring, snap the offsets free, and set them out on their own, where they take a single growing season to reach mature size.
Myths
Caladiums need full sun to develop their bright leaf colors.
It works the other way around. The color comes in deepest under partial or dappled shade, while too much direct sun fades the reds, pinks, and whites toward green and scorches the fragile leaves.
You can plant caladium tubers in early spring like other hardy bulbs.
Caladiums are tropical and rot or stall in cool ground. Wait until the soil reaches at least 60°F to 70°F (16°C to 21°C) before the tubers go in, which usually means late spring rather than the first warm day.