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Kentia palm 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 Kentia palm (Howea forsteriana), using what its sources say about pests and diseases, humidity and watering and 6 problems recorded for it.

Sources last read 14 September 2026.

Start the diagnosis for this Kentia palm

Kentia palm (Howea forsteriana), the whole plant.
Granitethighs, CC BY-SA 3.0 · Wikimedia Commons

Howea forsteriana, the Kentia palm, thatch palm or palm court palm, is a species of flowering plant in the palm family, Arecaceae, endemic to Lord Howe Island in Australia. It is also widely grown on Norfolk Island. Wikipedia, CC BY-SA 4.0

Native range: Lord Howe I. (wet tropical). Also sold as flat palm, Forster sentry palm, paradise palm, Sentry Palm, Thatch Palm and thatch-leaf palm.

What Kentia palm’s sources say that bears on this

Pests and diseases
Can be troubled by mealybugs (including root mealybugs), fern scale, greenhouse thrips and banded greenhouse thrips. Diseases: sooty molds.
NC State Extension · read 13 September 2026
Can be troubled by scale insects, thrips 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
During growth, water moderately, keep humidity moderate and feed monthly with a liquid fertiliser through summer. Give little water in winter.
RHS · read 13 September 2026

How this shows up on a Kentia palm

A black, sooty film on sticky leaves

The fronds of the kentia palm look dirty and dull, coated in black that comes off on a damp cloth.

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 2026

Pale stippled leaves and tiny moving dots underneath: a mite pest

Seen side-on, the kentia palm looks dusty and bleached. Under a lens the undersides move with minute mites, and silk gathers where fronds 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

Silvery patches dotted with tiny black spots: thrips

Patches of the kentia palm turn silver-gray, with black specks of excrement, and new growth may be scarred.

RHS lists thrips among the pests it may attract. They rasp the surface cells and drink the contents, which leaves the silvered, empty tissue.

Telling it apart: The black specks. Silvering with black dots is thrips; pale dots without them point at mites.

RHS · read 13 September 2026

Slow growth and limp leaves, with white specks on the roots: root mealybugs

Nothing on the fronds explains the decline. The roots of the kentia palm carry small white waxy clusters, most thickly at the edge of the root ball.

NC State Extension lists root mealybugs among its pests. The damage is to the roots, so the symptoms above ground look like drought.

Telling it apart: Take the plant out of its pot. White waxy specks that smear are root mealybugs; fine white threads that do not are fungal growth.

NC State Extension · read 13 September 2026

Sticky leaves and immobile shell-like insects on the stems

The kentia palm 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.

RHS 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.

RHS · read 13 September 2026

White, cottony tufts in the joints of the fronds: mealybugs

Clusters of white wax sit where each frond joins the stem and along the undersides of the kentia palm. Lifted with a cotton swab, each tuft holds a soft, pale insect, and the fronds below are sticky.

NC State Extension lists mealybugs among the pests it may attract. Mealybugs pierce the stem and draw sap, which weakens new growth and leaves a sticky residue.

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.

NC State Extension · read 13 September 2026

Possible causes, likeliest first for a Kentia palm

  1. Most likely spider mites

    Ranked higher because Kentia palm'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 kentia palm 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 mealybugs

    Ranked higher because Kentia palm's recorded problems point this way.

    • White, cottony tufts in the joints of the fronds: mealybugs NC State Extension

    Why: Mealybugs are soft insects that cover themselves in white wax, which gives the cottony look.

    What to try:

    • Move the kentia palm 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.

    Check this with the questions

  3. Most likely scale insects

    Ranked higher because Kentia palm's recorded problems point this way.

    • Sticky leaves and immobile shell-like insects on the stems RHS

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

    What to try:

    • Move the kentia palm 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 kentia palm does not move.

    Check this with the questions

Less likely for a Kentia palm, still possible

Questions

What usually causes pests on a Kentia palm?
For Kentia palm: spider mites, mealybugs and scale insects.
How can I tell which one it is on my Kentia palm?
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 Kentia palm's sources say about its pests and diseases?
NC State Extension: Can be troubled by mealybugs (including root mealybugs), fern scale, greenhouse thrips and banded greenhouse thrips. Diseases: sooty molds. RHS: Can be troubled by scale insects, thrips and greenhouse red spider mite. Diseases: usually none.
What does this look like on a Kentia palm?
The fronds of the kentia palm look dirty and dull, coated in black that comes off on a damp cloth. Telling it apart: Stickiness. Sooty mold grows on sticky leaves; dry black spots are something else.

Something else wrong with the Kentia palm?

Everything the sources say about Kentia palm

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.