String of pearls 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 String of pearls (Curio rowleyanus), using what its sources say about pests and diseases, humidity and watering and 3 problems recorded for it.
Sources last read 18 September 2026.
Curio rowleyanus, syn. Senecio rowleyanus, is a flowering plant in the daisy family Asteraceae. Wikipedia, CC BY-SA 4.0
Native range: Cape Prov. (subtropical). Also sold as Bead Plant, Irish Beads, Necklace Plant, Rosary Vine, String of Beads and String of Marbles.
What String of pearls’s sources say that bears on this
- Pests and diseases
- Greenhouse red spider mite, aphids and whitefly can attack it. Disease is uncommon.RHS · read 13 September 2026
- Humidity
- Most foliage plants prefer more humidity than a heated room gives; succulents are named as an exceptionPenn State Extension · read 13 September 2026
- Watering
- It copes with infrequent watering, but too much water can cause root rot. The rounded leaves expose less surface to dry desert air, so they lose less water or moisture.NC State Extension · read 13 September 2026Over winter, give little water and hold the temperature between 13°C and 16°C (55-60°F).RHS · read 13 September 2026
How this shows up on a String of pearls
Dull, finely mottled leaves and faint webs: spider mites
The leaves of the string of pearls lose their shine and fill with tiny pale dots. In a heavy infestation fine webbing strings across the shoot tips.
RHS lists spider mites among the pests it may attract. They feed from the underside, so the damage shows on top long before the mites are noticed.
Telling it apart: Webbing. Only mites spin fine silk at the shoot tips.
RHS · read 13 September 2026Sticky buds and shoot tips crowded with small insects
Aphids gather on the undersides of new leaves and around buds on the string of pearls, leaving honeydew and shed skins behind.
RHS lists aphids among the pests it may attract. Colonies build within days on young shoots, and the honeydew they shed makes the leaves sticky.
Telling it apart: Where they sit. Aphids crowd soft tips and buds; scale sits still on older stems.
RHS · read 13 September 2026Tiny white insects that fly up when the plant is touched: whitefly
Brushing the string of pearls lifts a cloud of tiny white insects. The undersides of the leaves carry pale, scale-like young, and the surfaces below are sticky.
RHS lists whitefly among the pests it may attract. Their honeydew is what makes the leaves sticky and lets a black film grow on them.
Telling it apart: Shake the plant. A cloud of white insects is whitefly; nothing else on a houseplant flies up like that.
RHS · read 13 September 2026Possible causes, likeliest first for a String of pearls
Most likely spider mites
Ranked higher because String of pearls's recorded problems point this way.
- Dull, finely mottled leaves and faint webs: spider mites RHS
Why: Spider mites feed on individual leaf cells, and each emptied cell shows as a pale speck.
What to try:
- Move the string of pearls 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 aphids
Ranked higher because String of pearls's recorded problems point this way.
- Sticky buds and shoot tips crowded with small insects 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 fungus gnats, which point at wet potting mix
Ranked higher for String of pearls because of what its sources say.
String of pearls stores water in its own tissue, which makes it more sensitive to wet soil than most leafy plants, so this reading is stronger for it.
Why: Fungus gnats lay their eggs in moist potting mix, and their larvae feed on organic matter and fungi in it.
What to try:
- Let the top two inches of potting mix dry between waterings; the larvae need it wet.Useful: moisture meter
- Yellow sticky traps near the soil catch the adults and show whether the numbers fall.Useful: sticky traps
What would settle it: Put a slice of raw potato on the soil for a day. Tiny translucent larvae on the underside confirm them.
Less likely for a String of pearls, still possible
Questions
- What usually causes pests on a String of pearls?
- For String of pearls: spider mites, aphids and fungus gnats.
- How can I tell which one it is on my String of pearls?
- 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 String of pearls's sources say about its pests and diseases?
- RHS: Greenhouse red spider mite, aphids and whitefly can attack it. Disease is uncommon.
- What does this look like on a String of pearls?
- The leaves of the string of pearls lose their shine and fill with tiny pale dots. In a heavy infestation fine webbing strings across the shoot tips. Telling it apart: Webbing. Only mites spin fine silk at the shoot tips.
- Is String of pearls safe to handle while I check it?
- Its sources list it as toxic to people. Wash your hands after handling the roots or sap, and keep trimmings away from pets.
Other plants that show pests
Purple passionCurled, sticky new leaf blades with green or black insects: aphids
AlocasiaFine pale speckling on the leaves, then webbing at the tips: spider mites
Aloe veraSticky leaves and immobile shell-like insects on the stems
Areca palmDull, finely mottled fronds and faint webs: spider mites
Arrowhead plantCurled, sticky new leaf blades with green or black insects: aphids
Asparagus fernCurled, sticky new fronds with green or black insects: aphids
Something else wrong with the String of pearls?
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.