Madagascar periwinkle 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 Madagascar periwinkle (Catharanthus roseus), using what its sources say about pests and diseases, humidity and watering and 2 problems recorded for it.
Sources last read 14 September 2026.
Catharanthus roseus, commonly known as bright eyes, Cape periwinkle, graveyard plant, Madagascar periwinkle, old maid, pink periwinkle, rose periwinkle, is a perennial species of flowering plant in the family Apocynaceae. It is native and endemic to Madagascar, but is grown elsewhere as an ornamental and medicinal plant, and now has a pantropical distribution. Wikipedia, CC BY-SA 4.0
Native range: E. & S. Madagascar (seasonally dry tropical). Also sold as Annual Vinca, Cape periwinkle, cayenne jasmine, East Indian periwinkle, old maid and Periwinkle.
What Madagascar periwinkle’s sources say that bears on this
- Pests and diseases
- Diseases: southern bacterial wilt, Phytophthora blight and root rot, black root rot.NC State Extension · read 13 September 2026Can be troubled by greenhouse red spider mite and greenhouse whitefly. Diseases: usually none.RHS · read 13 September 2026
- Humidity
- ASHRAE recommends indoor relative humidity between 30% and 60%Penn State Extension · read 13 September 2026
- Watering
- During growth, water moderately and feed monthly with a balanced liquid fertiliser. Give little water in winter.RHS · read 13 September 2026
How this shows up on a Madagascar periwinkle
Fine pale speckling on the leaves, then webbing at the tips: spider mites
The leaves of the Madagascar periwinkle 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. Heated rooms suit them: dry, warm air speeds each generation, and the damage builds within weeks.
Telling it apart: Tap a leaf over white paper. Dots that crawl are mites; dust stays still.
RHS · read 13 September 2026Tiny white insects that fly up when the plant is touched: whitefly
Brushing the Madagascar periwinkle 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. The young stay fixed under the leaves feeding, so the population keeps growing after the adults are cleared.
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 Madagascar periwinkle
Most likely spider mites
Ranked higher because Madagascar periwinkle's recorded problems point this way.
- Fine pale speckling on the leaves, then webbing at the tips: 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 madagascar periwinkle 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 madagascar periwinkle 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.
Most likely scale insects
Why: Scale insects settle in one place under a hard or waxy shell and feed on sap.
What to try:
- Move the madagascar periwinkle away from other plants.
- Scrape the scales off with a fingernail or a soft brush, then wipe the stems and leaves.
What would settle it: Push a bump gently with a fingernail. Scale comes away and leaves a mark; a bump that is part of the madagascar periwinkle does not move.
Less likely for a Madagascar periwinkle, still possible
Questions
- What usually causes pests on a Madagascar periwinkle?
- For Madagascar periwinkle: spider mites, mealybugs and scale insects.
- How can I tell which one it is on my Madagascar periwinkle?
- 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 Madagascar periwinkle's sources say about its pests and diseases?
- NC State Extension: Diseases: southern bacterial wilt, Phytophthora blight and root rot, black root rot. RHS: Can be troubled by greenhouse red spider mite and greenhouse whitefly. Diseases: usually none.
- What does this look like on a Madagascar periwinkle?
- The leaves of the Madagascar periwinkle lose their shine and fill with tiny pale dots. In a heavy infestation fine webbing strings across the shoot tips. Telling it apart: Tap a leaf over white paper. Dots that crawl are mites; dust stays still.
- Is Madagascar periwinkle safe to handle while I check it?
- Its sources list it as toxic to cats and dogs. Wash your hands after handling the roots or sap, and keep trimmings away from pets.
Other plants that show pests
OleanderCurled, sticky new leaves with green or black insects: aphids
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 Madagascar periwinkle?
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.