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Crape myrtle 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 Crape myrtle (Lagerstroemia indica), using what its sources say about pests and diseases and humidity and 4 problems recorded for it.

Sources last read 14 September 2026.

Start the diagnosis for this Crape myrtle

Crape myrtle (Lagerstroemia indica), the whole plant.
Gabriel Collares, CC BY 4.0 · Wikimedia Commons

Lagerstroemia indica, known as the crape myrtle, is a species of flowering plant in the genus Lagerstroemia of the family Lythraceae. It is native to East Asia, South Asia and Southeast Asia. Wikipedia, CC BY-SA 4.0

Native range: Himalaya to S. China and Indo-China (subtropical). Also sold as Common Crape Myrtle, Crape Flower, crapemyrtle, crepe flower, Crepe Myrtle and Indian crape myrtle.

What Crape myrtle’s sources say that bears on this

Pests and diseases
Can be troubled by crape myrtle pests, including crapemyrtle aphid, crapemyrtle flea beetle and crapemyrtle bark scale.
NC State Extension · read 13 September 2026
When grown indoors, greenhouse whitefly and greenhouse red spider mite can occur. Diseases: rarely, honey fungus.
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 a Crape myrtle

Clusters of small soft insects on the shoot tips and buds: aphids

Aphids gather on the undersides of new leaves and around buds on the crape myrtle, leaving honeydew and shed skins behind.

NC State Extension 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: 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 2026

Dull, finely mottled leaves and faint webs: spider mites

Seen side-on, the crape myrtle 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 2026

Small white flying insects under the leaves

The leaves of the crape myrtle yellow and grow sticky, sometimes dusted black, and white insects rest on the undersides.

RHS lists whitefly among the pests it may attract. Adults and young feed on sap from the undersides and shed honeydew, and warm indoor conditions keep them breeding.

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 2026

Sticky leaves and immobile shell-like insects on the stems

The crape myrtle is sticky to the touch and yellows slowly. Along the veins on the undersides sit small shell-like scales that lift off with a fingernail.

NC State Extension lists scale insects among the pests it may attract. The insect settles under a waxy shell and feeds on sap for life, so a colony builds quietly along the stems.

Telling it apart: Flick a bump with a fingernail. Scale comes away and leaves a mark; a natural bump on the stem does not move.

NC State Extension · read 13 September 2026

Possible causes, likeliest first for a Crape myrtle

  1. Most likely spider mites

    Ranked higher because Crape myrtle'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 crape myrtle 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.

    Check this with the questions

  2. Most likely scale insects

    Ranked higher because Crape myrtle's recorded problems point this way.

    • Sticky leaves and immobile shell-like insects on the stems NC State Extension

    Why: Scale insects settle in one place under a hard or waxy shell and feed on sap.

    What to try:

    • Move the crape myrtle 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 crape myrtle does not move.

    Check this with the questions

  3. Most likely aphids

    Ranked higher because Crape myrtle's recorded problems point this way.

    • Clusters of small soft insects on the shoot tips and buds: aphids NC State Extension

    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.

    Check this with the questions

Less likely for a Crape myrtle, still possible

Questions

What usually causes pests on a Crape myrtle?
For Crape myrtle: spider mites, scale insects and aphids.
How can I tell which one it is on my Crape myrtle?
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 Crape myrtle's sources say about its pests and diseases?
NC State Extension: Can be troubled by crape myrtle pests, including crapemyrtle aphid, crapemyrtle flea beetle and crapemyrtle bark scale. RHS: When grown indoors, greenhouse whitefly and greenhouse red spider mite can occur. Diseases: rarely, honey fungus.
What does this look like on a Crape myrtle?
Aphids gather on the undersides of new leaves and around buds on the crape myrtle, leaving honeydew and shed skins behind. Telling it apart: Whether you can see them. Aphids are visible to the eye; the mites that distort new growth are not.

Something else wrong with the Crape myrtle?

Everything the sources say about Crape myrtle

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.