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Lacy tree philodendron 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 Lacy tree philodendron (Thaumatophyllum bipinnatifidum), using what its sources say about pests and diseases, humidity and watering and 3 problems recorded for it.

Sources last read 18 September 2026.

Start the diagnosis for this Lacy tree philodendron

Lacy tree philodendron (Thaumatophyllum bipinnatifidum), the whole plant.
Marcin Konsek, CC BY-SA 4.0 · Wikimedia Commons

Philodendron bipinnatifidum, synonyms including Thaumatophyllum bipinnatifidum and Philodendron selloanum, is a plant in the genus Philodendron, in the family Araceae. The species is native to South America, namely to Brazil, Bolivia, Argentina, and Paraguay, but is also cultivated as a landscape plant in tropical, subtropical and warm temperate climates. Wikipedia, CC BY-SA 4.0

Native range: E. Bolivia to SE. & S. Brazil and NE. Argentina (seasonally dry tropical). Also sold as Cut-leaf Philodendron, fiddle-leaf philodendron, Heartleaf Philodendron, Horsehead Philodendron, panda plant and Split Leaf Philodendron.

What Lacy tree philodendron’s sources say that bears on this

Pests and diseases
Can be troubled by banded greenhouse thrips.
NC State Extension · read 13 September 2026
Greenhouse red spider mite and scale insects can attack it. Disease is uncommon.
RHS · read 13 September 2026
Humidity
ASHRAE recommends indoor relative humidity between 30% and 60%
Penn State Extension · read 13 September 2026
Watering
Salt buildup harms it, so flush the soil often, let rain fall on it, or water with distilled water. It may form aerial roots that take up water and nutrients.
NC State Extension · read 13 September 2026
During growth, water moderately and feed monthly with a balanced liquid fertiliser. At other times water sparingly.
RHS · read 13 September 2026

How this shows up on a Lacy tree philodendron

Fine pale speckling on the leaf blades, then webbing at the tips: spider mites

The leaf blades of the lacy tree philodendron 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: Webbing. Only mites spin fine silk at the shoot tips.

RHS · read 13 September 2026

Silver-flecked leaves and marked or distorted flowers: an insect pest

The surface of the leaf blades of the lacy tree philodendron looks scraped and silvered, and slender insects smaller than a grain of rice run or jump when disturbed.

NC State Extension 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.

NC State Extension · read 13 September 2026

Sticky leaves and immobile shell-like insects on the stems

The lacy tree philodendron 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 shell protects the insect, so it survives a wipe that would clear aphids and keeps feeding.

Telling it apart: Whether the bumps sit on the veins. Scale follows the sap; spots from disease scatter across the leaf.

RHS · read 13 September 2026

Possible causes, likeliest first for a Lacy tree philodendron

  1. Most likely spider mites

    Ranked higher because Lacy tree philodendron's recorded problems point this way.

    • Fine pale speckling on the leaf blades, 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 lacy tree philodendron 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 Lacy tree philodendron'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 lacy tree philodendron 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 lacy tree philodendron does not move.

    Check this with the questions

  3. Most likely mealybugs

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

    What to try:

    • Move the lacy tree philodendron 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

Less likely for a Lacy tree philodendron, still possible

Questions

What usually causes pests on a Lacy tree philodendron?
For Lacy tree philodendron: spider mites, scale insects and mealybugs.
How can I tell which one it is on my Lacy tree philodendron?
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 Lacy tree philodendron's sources say about its pests and diseases?
NC State Extension: Can be troubled by banded greenhouse thrips. RHS: Greenhouse red spider mite and scale insects can attack it. Disease is uncommon.
What does this look like on a Lacy tree philodendron?
The leaf blades of the lacy tree philodendron lose their shine and fill with tiny pale dots. In a heavy infestation fine webbing strings across the shoot tips. Telling it apart: Webbing. Only mites spin fine silk at the shoot tips.
Is Lacy tree philodendron 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.

Something else wrong with the Lacy tree philodendron?

Everything the sources say about Lacy tree philodendron

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.