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Calla lily

Zantedeschia aethiopica, Araceae

Sources last read 14 September 2026.

Middling It gives warning, with time to act.

Also called African lily, altar lily, Arum Lily, Brosimun aethiopica, Calla aethiopica, Egyptian lily, Florist's Calla, Garden Calla, lily of the Nile, Pig Lily, richardia, trumpet lily, white arum lily and White or common arum lily.

Calla lily (Zantedeschia aethiopica), the whole plant.
Krzysztof Ziarnek, Kenraiz, CC BY-SA 4.0 · Wikimedia Commons

Calla lily is toxic

  • Toxic to cats. Toxic principle: Insoluble calcium oxalates. Clinical signs: Oral irritation, pain and swelling of mouth, tongue and lips, excessive drooling, vomiting (not horses), difficulty swallowing. ASPCA
  • Toxic to dogs. Toxic principle: Insoluble calcium oxalates. Clinical signs: Oral irritation, pain and swelling of mouth, tongue and lips, excessive drooling, vomiting (not horses), difficulty swallowing. ASPCA
  • Toxic to people. Harmful when eaten; irritates skin and eyes. Use gloves and protective gear when handling it. RHS

What the sources say about its care

Light
Full sun, Partial shade
RHS · read 13 September 2026
Water
Poorly-drained
RHS · read 13 September 2026
Humidity

No source read publishes a humidity figure for any plant on this site. What follows is general guidance for foliage plants.

ASHRAE recommends indoor relative humidity between 30% and 60% 30–60%
Penn State Extension · read 13 September 2026
Temperature

How cold this tolerates, not what it prefers. No source read for this site publishes a preferred range for a plant indoors.

H4 — -10 to -5°C -10 to -5 °C
RHS · read 13 September 2026
Soil
Clay, Loam; pH Acid or Alkaline or Neutral
RHS · read 13 September 2026
Toxic to cats
Toxic
ASPCA · read 13 September 2026
Toxic to dogs
Toxic
ASPCA · read 13 September 2026
Harmful to people
Harmful when eaten; irritates skin and eyes. Use gloves and protective gear when handling it.
RHS · read 13 September 2026

How it usually goes wrong

Edges of the leaves brown while the middle stays sound

Leaves on the side of the calla lily nearest a heater or vent brown at the edges while those on the far side stay clean.

Penn State Extension cites ASHRAE's recommended indoor range of 30% to 60% relative humidity; a heated room in winter drops below it. Air that dry pulls water from the leaf faster than the roots replace it, and the margins are furthest from the supply. That applies while it is grown indoors; its RHS rating of H4 describes a plant that also grows outside, where the air is seldom that dry.

Telling it apart: Whether the damage advances. Dry air marks a leaf and stops; rot keeps going.

Penn State ExtensionCalla lily brown leaf tips and edges: causes
Leaves bruised and browned along the edges after a gale

After a windy night the calla lily shows fresh brown edges and a few torn leaves, all facing the same way.

Its source describes a sheltered spot. In an exposed one, wind both dries the leaves and damages them physically, which is why the marks follow the direction of the weather.

Telling it apart: The pattern of the damage. Tears and bruises point at wind; soft, spreading patches point at rot or disease.

RHSCalla lily brown leaf tips and edges: causes
Leaves but no flowers

The calla lily flowered well at first, then less each season, while its leaves stayed healthy and new stems grew longer.

Its source places it in full sun, partial shade. Flowers cost more than leaves, and a plant kept darker than that keeps growing leaves while it builds few buds or none.

Telling it apart: Whether the stems have stretched. Leafy, stretched growth with no buds points at light; normal spacing points at timing, feeding or a season it has not had.

RHSCalla lily not flowering or dropping buds: causes
Pale dry areas across the upper leaves only

Affected tissue goes pale and then papery, and the boundary follows where the light falls rather than the shape of the leaf.

Its source names full sun, partial shade, yet a leaf grown in lower light has thinner tissue than one grown in sun, and it scorches if moved into strong light in one step.

Telling it apart: Which side. Damage confined to the lit side is light; damage spread evenly is not.

RHSCalla lily leaves turning yellow: causes
The lowest leaves on each stem turn yellow and hang

A sour smell from the compost is common on a calla lily, and the lowest leaves on each stem come away when pulled. The surface may look dry while everything beneath it is not.

Kept wetter than the poorly-drained its source describes, the root tips die back. A plant with fewer working roots cannot drink, which looks from above exactly like one that has not been watered.

Telling it apart: The smell. Healthy compost smells of earth; compost that has been wet too long does not.

RHSCalla lily leaves turning yellow: causes

Not sure which it is? Ask the diagnosis questions for Calla lily.

Routine care

Watering
They can survive in water up to 12" deep, so they suit pond margins or rain gardens.
NC State Extension · read 13 September 2026
Plant outside in part shade or full sun, in soil that holds moisture; in containers use peat-free potting compost (John Innes No2), or grow it at the margins in water to a depth of 30cm (1ft).
RHS · read 13 September 2026
Feeding
Pests, diseases and other problems: the leaves and flowers may be eaten by Japanese beetles.
NC State Extension · read 13 September 2026
Propagation
It usually grows in clumps and divides easily in early spring once frost danger is over, or once flowering ends in late summer or early fall.
NC State Extension · read 13 September 2026
Divide in spring.
RHS · read 13 September 2026
Pruning
Tidy away foliage that frost has blackened.
RHS · read 13 September 2026
Pests and diseases
Can be troubled by banded greenhouse thrips.
NC State Extension · read 13 September 2026
Thrips or aphids can occur. Diseases: a virus, and bacterial and fungal rots, can occur.
RHS · read 13 September 2026

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About the plant

Zantedeschia aethiopica, commonly known as calla lily, arum lily, and death lily, is a species of flowering plant in the family Araceae, native to southern Africa in Lesotho, South Africa, and Eswatini.

From Wikipedia, CC BY-SA 4.0 · read 13 September 2026

Native range
S. Africa
World Checklist of Vascular Plants, June 2026 release, CC BY.
Kew WCVP · read 13 September 2026
Southern Africa
NC State Extension · read 13 September 2026
S Africa, Lesotho
RHS · read 13 September 2026
Climate
seasonally dry tropical
World Checklist of Vascular Plants, June 2026 release, CC BY.
Kew WCVP · read 13 September 2026
Growth form
tuberous geophyte
World Checklist of Vascular Plants, June 2026 release, CC BY.
Kew WCVP · read 13 September 2026
Bulb, Perennial, Water Plant; habit clumping
NC State Extension · read 13 September 2026
Clump forming (deciduous)
RHS · read 13 September 2026
Size
Height 24–39 in; width 12–24 in
NC State Extension · read 13 September 2026
Height 0.5-1 metres; spread 0.1-0.5 metres after 5–10 years
RHS · read 13 September 2026
Flowering
Flowers white; blooms in summer
NC State Extension · read 13 September 2026
Flowers white in spring and summer; yellow in spring and summer
RHS · read 13 September 2026

Common problems with Calla lily

More of the Araceae family

Plants with similar care

Sources

What this does not cover

The figures above are what published sources say, not measurements of the plant in your room. They say nothing about your pot size, your water, the season, or how far from the glass the plant stands, and those decide more than any figure here does.

Humidity has no species figure because no source read for this site publishes one, and the only temperature published for this plant is a cold floor. The simulator fills those gaps with general figures for its kind of plant, marked as general and listed on how we read sources. Where a toxicity row says the plant was not assessed, that is the absence of a finding and not a finding of safety.

If something is already wrong, the diagnosis tool asks about the soil, the window and the watering, which is where the answer usually is.