spaWhole-plant symptoms

Pests

Tiny insects, mites, or visible signs of infestation on your indoor plant — most commonly caused by spider mites, mealybugs, scale insects, fungus gnats, or thrips.

Moderate RiskNeeds Closer CheckingBug or Pest

reportSeverity hint

Treatable if caught early. Isolate the affected plant to prevent spread to nearby plants. Most pest infestations can be resolved within 2-3 weeks with consistent treatment.

Key Symptoms

Match the visible pattern before looking for causes.

Fine webbing on leaves

Delicate, spider-like webbing appears between leaf veins, on leaf undersides, or between stems. This is distinct from ordinary spider webs because it's thinner, covers more surface area, and often has tiny moving specks within it.

White cottony masses

White, fluffy or cotton-like tufts appear on stems, leaf undersides, or in the joints where leaves meet stems. These look like small bits of cotton wool and are often clustered in groups.

Small black flies

Tiny black flies about 1/8 inch long that fly around the plant, especially after watering or when you move the plant. They're most noticeable on windows or walls near infested plants.

Bump-like structures on stems

Small brown, gray, or white bumps attached to stems, twigs, or leaf undersides. They don't move when touched and can be scraped off with a fingernail, leaving a mark underneath.

Silvery streaks on leaves

Irregular silvery or metallic-looking streaks, blotches, or washed-out patches on leaf surfaces. You may also see tiny black specks of insect waste near the damaged areas.

Sticky residue or black mold

Leaves or stems feel sticky or shiny from a sugary substance (honeydew), and/or there's black sooty mold growing on this sticky coating. This often appears below where pests are clustered.

Start With What You See

Choose the situation that best matches your plant.

You see distinct white cottony or fuzzy masses on stems, leaf undersides, or where leaves meet stems, appearing especially in protected corners or after bringing new plants nearby

Look for white, fluffy tufts that resemble small bits of cotton wool. These are often clustered in groups and appear most commonly in leaf axils or on the undersides of leaves.

Likely cause: Mealybugs

See Treatmentarrow_forward

You find fine webbing on leaves, especially between leaf veins or on new growth, particularly in warm, dry conditions or near heat vents

Check for delicate, spider-like webbing that covers multiple leaves or stems. Unlike ordinary spider webs, this webbing often contains tiny moving specks and spreads more extensively across plant surfaces.

Likely cause: Spider Mites

See Treatmentarrow_forward

Leaves or stems feel sticky, or there's black sooty mold growing on the plant, especially on surfaces directly below sticky or clustered areas

Touch the leaves to feel for a shiny, sugary residue. Look for dark, velvety black mold growing on this sticky coating, particularly on upper leaf surfaces where honeydew drips down.

Continue to Diagnostic flowarrow_forward

Small flies are flying around the plant, especially when you water or move it, and they're most noticeable on windows or walls nearby

Observe the plant during and after watering. Tiny black flies that swarm up from the soil or fly around when the plant is disturbed indicate fungus gnats.

Likely cause: Fungus Gnats

See Treatmentarrow_forward

Leaves have silvery streaks, blotches, or look washed out, sometimes with tiny black dots, and the damage appeared recently especially on new growth or flower buds

Inspect leaf surfaces for irregular silvery or metallic patches that give leaves a faded, dull appearance. Look closely for tiny black specks of insect waste, especially near leaf edges or damaged flower buds.

Continue to Diagnostic flowarrow_forward

Not sure what you're seeing, or multiple things seem true

If you're uncertain about the symptoms or if your plant shows multiple signs, proceed through the diagnostic checklist to identify the pest based on specific, observable characteristics.

Continue to Diagnostic flowarrow_forward

Common Causes

Start from the top. Match what you can observe, then use one check to confirm.

Spider Mites

Best Match If

checkFine webbing appears on leaves, especially between leaf veins and on new growth
checkLeaves have tiny speckled or stippled dots on the upper surface that look like sandpaper when rubbed
checkLower leaves look bronzed, gray, or overall faded and pale
checkDamage is worse in warm, dry conditions and on plants near heat vents

Next Check

Hold a white sheet of paper under a branch and tap it firmly. If tiny specks fall and start moving, you have spider mites.

Why It Happens

Spider mites pierce plant cells with needle-like mouthparts and suck out the sap. This creates tiny wounds that appear as stippled dots. As feeding continues, leaves lose chlorophyll and develop a bronzed appearance. Spider mites thrive in warm, dry conditions and produce fine webbing to protect themselves and move between plants.

Mealybugs

Best Match If

checkWhite cottony masses or tufts appear on stems, leaf undersides, or in leaf axils where leaves meet stems
checkLeaves or stems feel sticky from honeydew, a shiny sugary substance
checkBlack sooty mold grows on the sticky honeydew, especially on upper leaf surfaces
checkInsects look like small oval blobs covered in white powdery wax, often clustered in groups

Next Check

Inspect the undersides of leaves and leaf axils with a magnifying glass for white cottony masses. Look especially near where new leaves are emerging.

Why It Happens

Mealybugs are soft-bodied insects covered in a white waxy coating that protects them. They insert their piercing-sucking mouthparts into plant tissue and feed on sap. This weakens the plant and causes distorted, stunted growth. As they feed, they excrete excess sugars as honeydew, which provides ideal conditions for sooty mold fungi to grow.

Scale Insects

Best Match If

checkBrown, gray, or white bump-like structures appear on stems, twigs, or undersides of leaves
checkThe bumps can be scraped off but leave a mark underneath; they don't move when touched
checkSticky residue or sooty mold appears specifically below where the hard bumps are clustered
checkLeaves yellow and drop prematurely, especially on the affected branches

Next Check

Run your fingernail along the stem and leaf midribs. If you feel small bumps that can be scraped off, you likely have scale insects.

Why It Happens

Scale insects are immobile pests that secrete a hard, protective shell covering that makes them resemble bumps on the plant. They insert their mouthparts into plant tissue and feed continuously on sap. This saps the plant's energy and causes leaf yellowing and premature drop. Soft scale insects excrete honeydew, which leads to sooty mold growth.

Fungus Gnats

Best Match If

checkTiny black flies about 1/8 inch long fly around the plant when you water or move it
checkAdult flies are most active right after watering, when the soil surface is wet
checkSmall translucent white larvae visible on the soil surface when the top layer is gently disturbed
checkFlies are most noticeable on windows or walls near infested plants

Next Check

Place a slice of raw potato on the soil surface and check it in 24-48 hours. If you see tiny worm-like larvae feeding on it, you have fungus gnats.

Why It Happens

Fungus gnats are small flies that develop in potting soil. The adults are mainly a nuisance, but their larvae live in the soil and feed on fungi, decaying organic matter, and root hairs. While established plants usually tolerate light feeding, heavy larval infestations can damage roots—especially on seedlings and young plants—causing reduced vigor and leaf loss. Fungus gnats thrive in consistently moist soil.

Thrips

Best Match If

checkLeaves develop irregular silvery streaks, blotches, or a washed-out dull appearance
checkTiny black specks of excrement appear on leaves, especially near leaf edges
checkFlower buds or petals are streaked, distorted, or fail to open properly
checkTapping or blowing on affected leaves causes tiny slender insects to scramble quickly

Next Check

Hold a white sheet of paper under the affected plant and shake the leaves gently. If tiny slender insects fall onto the paper and move quickly, you have thrips.

Why It Happens

Thrips are tiny, slender insects that feed by scraping plant tissue and sucking out the cell contents. This scraping action creates silvery streaks and blotches on leaves as the surface cells are damaged. They also leave behind distinctive black fecal specks. Thrips can distort flower buds by feeding inside them before they open, causing scarring and preventing proper development.

Diagnostic Flow

Check these in order. If one answer lands on a likely conclusion, treat that as your stopping point before moving into the matching treatment.

Do you see any fine webbing on the leaves or between stems?

If yesthere's webbing

Likely cause

Spider Mites

If noNo webbing

Proceed to check for white cottony masses on stems or leaf undersides.

Not sureHard to tell if there's webbing or not

Hold a white sheet of paper under the plant and tap it. If tiny moving specks appear with webbing, it's likely spider mites.

Do you see white cottony or fuzzy masses on stems, leaf undersides, or where leaves meet stems?

If yesthere are white cottony masses

Likely cause

Mealybugs

If noNo white cottony masses

Proceed to check for bump-like structures on stems or leaf undersides.

Not sureHard to tell if there are cottony masses or not

Use a magnifying glass to inspect leaf undersides and stem joints. White cottony masses are distinct and look like small bits of cotton wool.

Do you see bump-like structures on stems or leaf undersides? (They might be brown, gray, or white and don't move when touched)

If yesthere are bump-like structures

Likely cause

Scale Insects

If noNo bump-like structures

Proceed to check for small flies around the plant or silvery streaks on leaves.

Not sureHard to tell if there are bump-like structures or not

Run your fingernail along stems and leaf midribs. If you feel small bumps that can be scraped off, you likely have scale insects.

Are there small flies flying around the plant, especially when you water or move it?

If yesthere are flies around the plant

Likely cause

Fungus Gnats

If noNo flies

Proceed to check for silvery streaks or blotches on leaves, which would indicate thrips.

Not sureHard to tell if there are flies around or not

Water the plant and observe closely. Tiny black flies that swarm from the soil are fungus gnats. If no flies appear, look for leaf damage instead.

Do you see silvery streaks, blotches, or washed-out patches on the leaves?

If yesthere are silvery streaks or blotches

Likely cause

Thrips

If noNo silvery streaks

Re-examine the plant for any overlooked signs: webbing, cottony masses, bumps, or flies. If still uncertain, review the common causes section for detailed comparisons.

Not sureHard to tell if there are silvery streaks or not

Hold a white sheet under the plant and shake the leaves gently. Tiny slender insects that move quickly indicate thrips. Silvery leaf damage is also characteristic.

Treatment

Start with safe stabilizing actions, then follow the plan that matches the diagnosed cause.

Safe while diagnosing

These low-risk actions help stabilize the plant before you know the exact cause.

checkIsolate the plant from other plants to prevent pests from spreading

Treatment plan by cause

Spider Mites

Use this plan if fine webbing appears on leaves, especially between leaf veins and on new growth, or leaves have tiny speckled or stippled dots on the upper surface that look like sandpaper when rubbed.

Today

Move the plant to a cooler room away from other plants
Spray the plant with a forceful stream of water to dislodge mites
Increase humidity around the plant to discourage mite reproduction

Next a few weeks

Check the undersides of leaves every 3-4 days for new mite activity
Keep the soil moist but not saturated to maintain higher humidity
Repeat water spray every 3-4 days for 2 weeks until no signs remain

What to expect

Webbing should stop appearing within 7-10 days and leaf damage should not worsen
Leaves already speckled or bronzed will not recover their color
If webbing or new speckling continues after 2 weeks, consider using miticide or discard heavily infested plants

Don't do this

Well-meant fixes that can make the problem harder to diagnose.

Treating all pests with the same spray without identifying what you have

check_circle

Different pests require different treatments. Spider mites are arachnids, not insects, so many insecticides won't work on them. Scale insects have protective shells that need oils or physical removal. Identify the pest first, then choose the appropriate treatment method.

Applying pesticide only once and stopping when you don't see immediate results

check_circle

Most pest life cycles require multiple treatments to be effective. Eggs hatch in waves, and treatments don't kill all stages. Follow the product label for reapplication intervals, typically every 5-14 days for 3-6 weeks, to break the pest's reproductive cycle.

Keeping heavily infested plants because they might recover

check_circle

Some infestations, especially severe scale, mealybug, or cyclamen mite problems, are extremely difficult to control and can spread to your entire collection. It's often better to discard one heavily infested plant than to risk multiple plants and weeks of ineffective treatment attempts.

Using dish soap instead of insecticidal soap for pest control

check_circle

Dish soap can burn plant tissues and doesn't have the proper formulation to effectively control pests. Use insecticidal soap specifically labeled for houseplants, which is designed to penetrate insect exoskeletons without harming plant tissue.

Watering plants with pest problems to help them recover

check_circle

Overwatering stressed plants can cause root rot and create conditions favorable for fungus gnats and other pests. Maintain normal watering practices based on the plant's needs and soil moisture, not in response to the pest problem itself.