Oleander 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 Oleander (Nerium oleander), using what its sources say about pests and diseases and humidity and 5 problems recorded for it.
Sources last read 14 September 2026.
Nerium oleander, the oleander, is a shrub or small tree native to the Mediterranean region east to southern Asia, from Morocco and Portugal east to India and Myanmar; the Flora of China also cites it as native in Yunnan in China. It is the only species currently classified in the genus Nerium, belonging to subfamily Apocynoideae of the dogbane family Apocynaceae. Wikipedia, CC BY-SA 4.0
Native range: Medit. to Myanmar (subtropical). Also sold as East Indian oleander, Jamaica South Sea rose, laurier rose, rose bay, Rose Laurel and Rosebay.
What Oleander’s sources say that bears on this
- Pests and diseases
- Can be troubled by oleander aphid, milkweed bug and spinose scale, plus sooty molds.NC State Extension · read 13 September 2026In a greenhouse, greenhouse red spider mite, mealybugs and scale insects can attack it. Disease risks: it is a high-risk host of Xylella fastidiosa, and honey fungus occurs rarely.RHS · read 13 September 2026
- Humidity
- ASHRAE recommends indoor relative humidity between 30% and 60%Penn State Extension · read 13 September 2026
How this shows up on an Oleander
Curled, sticky new leaves with green or black insects: aphids
The youngest growth of the oleander is sticky and distorted, and a closer look finds colonies of small, pear-shaped insects.
NC State Extension lists aphids among the pests it may attract. They favor tender tips and buds, so the damage concentrates where the plant is growing.
Telling it apart: Whether you can see them. Aphids are visible to the eye; the mites that distort new growth are not.
NC State Extension · read 13 September 2026Dull, finely mottled leaves and faint webs: spider mites
Seen side-on, the oleander looks dusty and bleached. Under a lens the undersides move with minute mites, and silk gathers where leaves meet the stem.
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 2026Small raised bumps along the stems and veins, with sticky leaves: scale insects
Rows of small, hard scales sit where the veins of the oleander are thickest, and the surface below them is glossy with honeydew.
RHS lists scale insects among the pests it may attract. Each scale sits in one place drawing sap and dripping honeydew, which is why the leaves below turn sticky.
Telling it apart: Stickiness below the bumps. Scale drips honeydew; a leaf spot is dry.
RHS · read 13 September 2026Sticky leaves and white fluff where they meet the stem: mealybugs
The oleander carries white, cottony specks in its crevices, and growth slows. Leaves beneath the colonies turn sticky and, in time, dull or yellow.
RHS lists mealybugs among the pests it may attract. The wax keeps them dry and hard to reach, so they multiply in the sheltered joints of the plant.
Telling it apart: Where the white is. Mealybugs gather in joints and under leaves; a powdery coating across the top of a leaf is mildew.
RHS · read 13 September 2026Sticky leaves turning black on top
The upper surfaces of the leaves of the oleander are covered in a black, soot-like layer that wipes off to show green leaf beneath. The surface is sticky.
NC State Extension lists sooty mold among the diseases it may get. It does not infect the leaf but shades it, and it follows aphids, scale, mealybugs or whitefly.
Telling it apart: Stickiness. Sooty mold grows on sticky leaves; dry black spots are something else.
NC State Extension · read 13 September 2026Possible causes, likeliest first for an Oleander
Most likely spider mites
Ranked higher because Oleander'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 oleander 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
Ranked higher because Oleander's recorded problems point this way.
- Sticky leaves and white fluff where they meet the stem: mealybugs RHS
Why: Mealybugs are soft insects that cover themselves in white wax, which gives the cottony look.
What to try:
- Move the oleander 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
Ranked higher because Oleander's recorded problems point this way.
- Small raised bumps along the stems and veins, with sticky leaves: scale insects RHS
Why: Scale insects settle in one place under a hard or waxy shell and feed on sap.
What to try:
- Move the oleander 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 oleander does not move.
Less likely for an Oleander, still possible
Questions
- What usually causes pests on an Oleander?
- For Oleander: spider mites, mealybugs and scale insects.
- How can I tell which one it is on my Oleander?
- 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 Oleander's sources say about its pests and diseases?
- NC State Extension: Can be troubled by oleander aphid, milkweed bug and spinose scale, plus sooty molds. RHS: In a greenhouse, greenhouse red spider mite, mealybugs and scale insects can attack it. Disease risks: it is a high-risk host of Xylella fastidiosa, and honey fungus occurs rarely.
- What does this look like on an Oleander?
- The youngest growth of the oleander 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 Oleander 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
Madagascar periwinkleFine pale speckling on the leaves, then webbing at the tips: spider mites
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 Oleander?
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.