Cape leadwort 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 Cape leadwort (Plumbago auriculata), using what its sources say about pests and diseases, humidity and watering and 2 problems recorded for it.
Sources last read 14 September 2026.
Plumbago auriculata, the Cape leadwort, blue plumbago or Cape plumbago, is a species of flowering plant in the family Plumbaginaceae, native to South Africa and Mozambique. Wikipedia, CC BY-SA 4.0
Native range: Mozambique to S. Africa (subtropical). Also sold as Cape plumbago.
What Cape leadwort’s sources say that bears on this
- Pests and diseases
- Can be troubled by greenhouse whitefly and greenhouse red spider mite. 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
- Give container plants little water in winter.NC State Extension · read 13 September 2026In a greenhouse, give full light and use a peat-free potting mix that is loam-based; water generously during growth and feed monthly with a balanced liquid fertiliser.RHS · read 13 September 2026
How this shows up on a Cape leadwort
Pale stippled leaves and tiny moving dots underneath: a mite pest
Seen side-on, the cape leadwort 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. Mites empty the leaf cells one by one, which is what the pale dots are, and they breed fastest in warm, dry air.
Telling it apart: Where the damage starts. Mites stipple the whole leaf in fine dots; sun scorch bleaches the side facing the window.
RHS · read 13 September 2026Sticky, yellowing leaves and a cloud of white insects: whitefly
Brushing the cape leadwort 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: What lives under the leaves. Whitefly young are flat, pale ovals; mealybugs are woolly.
RHS · read 13 September 2026Possible causes, likeliest first for a Cape leadwort
Most likely spider mites
Ranked higher because Cape leadwort's recorded problems point this way.
- Pale stippled leaves and tiny moving dots underneath: a mite pest RHS
Why: Spider mites feed on individual leaf cells, and each emptied cell shows as a pale speck.
What to try:
- Move the cape leadwort 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 cape leadwort 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 cape leadwort 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 cape leadwort does not move.
Less likely for a Cape leadwort, still possible
Questions
- What usually causes pests on a Cape leadwort?
- For Cape leadwort: spider mites, mealybugs and scale insects.
- How can I tell which one it is on my Cape leadwort?
- 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 Cape leadwort's sources say about its pests and diseases?
- RHS: Can be troubled by greenhouse whitefly and greenhouse red spider mite. Diseases: usually none.
- What does this look like on a Cape leadwort?
- Seen side-on, the cape leadwort looks dusty and bleached. Under a lens the undersides move with minute mites, and silk gathers where leaves meet the stem. Telling it apart: Where the damage starts. Mites stipple the whole leaf in fine dots; sun scorch bleaches the side facing the window.
- Is Cape leadwort 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
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
Blue passion flowerPale stippled leaves and tiny moving dots underneath: a mite pest
Something else wrong with the Cape leadwort?
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.