Calla lily pests, webbing or sticky leaves: causes and what to do
6 results in the diagnosis tree begin with pests, 5 of them marked likely when the answers fit. They are ordered here for Calla lily (Zantedeschia aethiopica), using what its sources say about pests and diseases, humidity and watering and 2 problems recorded for it.
Sources last read 14 September 2026.
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. Wikipedia, CC BY-SA 4.0
Native range: S. Africa (seasonally dry tropical). Also sold as African lily, altar lily, Arum Lily, Brosimun aethiopica, Calla aethiopica and Egyptian lily.
What Calla lily’s sources say that bears on this
- Pests and diseases
- Can be troubled by banded greenhouse thrips.NC State Extension · read 13 September 2026Thrips or aphids can occur. Diseases: a virus, and bacterial and fungal rots, can occur.RHS · read 13 September 2026
- Humidity
- ASHRAE recommends indoor relative humidity between 30% and 60%Penn State Extension · read 13 September 2026
- Watering
- They can survive in water up to 12" deep, so they suit pond margins or rain gardens.NC State Extension · read 13 September 2026Plant outside in part shade or full sun, in soil that holds moisture; in containers use peat-free potting mix (John Innes No2), or grow it at the margins in water to a depth of 30cm (1ft).RHS · read 13 September 2026
How this shows up on a Calla lily
Curled, sticky new leaves with green or black insects: aphids
The youngest growth of the calla lily is sticky and distorted, and a closer look finds colonies of small, pear-shaped insects.
RHS lists aphids among the pests it may attract. They feed on the sap of soft new growth, which distorts it, and they multiply quickly without mating.
Telling it apart: Whether you can see them. Aphids are visible to the eye; the mites that distort new growth are not.
RHS · read 13 September 2026Silvery patches dotted with tiny black spots: thrips
Patches of the calla lily turn silver-gray, with black specks of excrement, and new growth may be scarred.
RHS lists thrips among the pests it may attract. They rasp the surface cells and drink the contents, which leaves the silvered, empty tissue.
Telling it apart: Shake a flower or leaf over white paper. Thrips show as tiny slender insects that move.
RHS · read 13 September 2026Possible causes, likeliest first for a Calla lily
Most likely aphids
Ranked higher because Calla lily's recorded problems point this way.
- Curled, sticky new leaves with green or black insects: aphids RHS
Why: Aphids cluster on soft new growth and flower buds, where the sap is easiest to reach.
What to try:
- Rub them off with fingers, or rinse them off in a sink or shower.
- Repeat every few days while new ones appear.
What would settle it: Look for the pale shed skins among the insects. Aphids molt as they grow, and the skins are left behind in the colony.
Most likely spider mites
Why: Spider mites feed on individual leaf cells, and each emptied cell shows as a pale speck.
What to try:
- Move the calla lily away from other plants.
- Wash the leaves, top and underside, with a strong spray of water in a shower or sink.
What would settle it: Hold a sheet of white paper under a leaf and tap the leaf. Tiny specks that move across the paper are mites.
Most likely mealybugs
Why: Mealybugs are soft insects that cover themselves in white wax, which gives the cottony look.
What to try:
- Move the calla lily away from other plants.
- Wipe off every insect you can see with a cotton swab dipped in rubbing alcohol, testing a single leaf first.
What would settle it: Touch a tuft with a cotton swab. If a small, pale, oval insect is underneath, it is a mealybug.
Less likely for a Calla lily, still possible
Questions
- What usually causes pests on a Calla lily?
- For Calla lily: aphids, spider mites and mealybugs.
- How can I tell which one it is on my Calla lily?
- What can you see? Fine webbing, and tiny pale speckles on the leaves; White, cottony tufts in the leaf joints; Small brown or pale bumps on stems and leaves that do not move; Clusters of small, soft insects on the new growth; Tiny dark flies around the soil; Sticky, shiny residue, but no insect I can see.
- What do Calla lily's sources say about its pests and diseases?
- NC State Extension: Can be troubled by banded greenhouse thrips. RHS: Thrips or aphids can occur. Diseases: a virus, and bacterial and fungal rots, can occur.
- What does this look like on a Calla lily?
- The youngest growth of the calla lily is sticky and distorted, and a closer look finds colonies of small, pear-shaped insects. Telling it apart: Whether you can see them. Aphids are visible to the eye; the mites that distort new growth are not.
- Is Calla lily safe to handle while I check it?
- Its sources list it as toxic to cats, dogs and people. Wash your hands after handling the roots or sap, and keep trimmings away from pets.
Other plants that show pests
Flamingo flowerHard, rounded scale on the undersides of the leaves
African violetIrregular notches bitten from leaf edges by an insect pest
Barberton daisyCurled, sticky new leaves with green or black insects: aphids
Bearded irisRagged holes and slime trails: a slug or snail pest
Bigleaf hydrangeaClusters of small soft insects on the shoot tips and buds: aphids
Bird of paradiseDull, finely mottled leaves and faint webs: spider mites
Something else wrong with the Calla lily?
What this does not cover
This page orders a decision tree's results using a plant's sourced care. It has not seen your plant, its pot or its window, and two problems at once are common: that is the usual reason a confident answer turns out wrong. The questions in the diagnosis tool narrow it further than a list can.