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Problem diagnosisHow to get rid of spider mites and mealybugs
Method verified against university horticulture extension guidance on 19 August 2026. Sources linked below.
Fine webbing and pale speckled leaves mean spider mites. White cottony clumps tucked in leaf joints mean mealybugs. Both spread fast and neither goes away on its own, so treat as soon as you spot either one, and repeat the treatment on a schedule because a single pass rarely kills the eggs.
You get rid of spider mites by washing them off with a forceful spray of water or wiping leaves down, then following up with insecticidal soap or horticultural oil every 7 to 14 days until they are gone. Mealybugs come off with a cotton swab dipped in isopropyl alcohol for small numbers, or a diluted alcohol spray for a heavier infestation, also repeated weekly. Neither pest is killed reliably by a single treatment, because most controls do not touch the eggs.
| Pest | What you see | How to treat it |
|---|---|---|
| Spider mites | Fine pale speckling (stippling) on leaves; fine webbing on the undersides and between stems in a heavier case | Forceful water spray or wipe-down, then insecticidal soap or horticultural oil, repeated every 7 to 14 days |
| Mealybugs | White, cottony clumps in leaf joints, along stems, or on leaf undersides; no webbing | Cotton swab dipped in isopropyl alcohol for light cases; a 10 to 25% alcohol spray for heavier ones, repeated weekly |
What are spider mites, and how do you spot them?
Spider mites are tiny sap-sucking arachnids, about 1/50th of an inch long, that feed on individual plant cells and leave behind a speckled or stippled look as the dead cells sit next to still-healthy green ones. They thrive in warm, dry conditions, which is exactly what most centrally heated homes provide over winter.
To confirm mites rather than guess from the speckling alone, tap a leaf over a sheet of white paper. Tiny specks that fall off and then crawl are mites; a hand lens or magnifying glass makes them easier to see. In a heavier infestation you will also see fine, silky webbing across the leaf undersides and between stems, which is the single clearest sign, because few other houseplant pests spin webbing at all.
How do you get rid of spider mites?
You get rid of spider mites by physically removing as many as you can, then following up with a repeat-application treatment, because most controls miss the eggs on the first pass.
- Wash them off. A forceful, lukewarm spray of water, or wiping larger leaves with a soft damp cloth, physically removes a large share of the population immediately.
- Isolate the plant from others while you treat it, since mites move readily to neighbouring foliage that is touching or close by.
- Apply insecticidal soap or horticultural oil, covering the leaf undersides where mites live. Repeat every 7 to 14 days, because most miticides do not kill eggs and a fresh generation hatches on that cycle.
- Increase humidity around the plant where practical (grouping plants, a pebble tray), since dry air is what let the population build up in the first place. Misting the leaves alone will not control an active infestation.
- If the infestation is severe, with most of the plant covered, discarding the plant is often the more reliable option than fighting it back from that point.
What are mealybugs, and how are they different from spider mites?
Mealybugs are small, soft-bodied insects that secrete a white, powdery wax over their bodies, and that wax is what you actually see: cottony clumps tucked into leaf joints, along stems, and on leaf undersides, rather than scattered speckling across the leaf surface. Adult females run about 1/20 to 1/5 inch long.
The clearest difference from spider mites is the wax versus the webbing. Mealybugs do not spin silk threads; what can look like fine webbing at a glance is usually dried honeydew (a sticky excretion) mixed with dust, or occasionally sooty mould growing on that honeydew. If you see true fine threads between leaves and stems, that is mites, not mealybugs.
How do you get rid of mealybugs?
You get rid of mealybugs by dissolving their waxy coating with alcohol, which then causes the insect to dry out and die, and by repeating the treatment weekly until no new clumps appear.
- For a light infestation, dip a cotton swab in isopropyl (rubbing) alcohol and dab or wipe it directly onto each visible mealybug. The alcohol strips the waxy coating that protects them.
- For a heavier infestation, mix a 10 to 25% isopropyl alcohol solution in a spray bottle and apply it thoroughly, including leaf joints and undersides where mealybugs cluster. Repeat weekly until the infestation clears.
- Test first. Try the alcohol on a small, inconspicuous part of the plant one to two days beforehand, since some plants can show leaf burn (phytotoxicity) from alcohol contact.
- For a heavy or stubborn case, follow up with insecticidal soap or a registered houseplant spray covering the whole plant, not just the visible clumps.
How do you stop them coming back?
You stop spider mites and mealybugs coming back by catching them early and not giving either one the conditions it needs to build up, since both pests establish quietly before you notice them:
- Inspect any new plant before it joins the others, checking leaf undersides and joints closely, because bringing in an infested plant is the most common way either pest arrives.
- Quarantine a new or recovering plant away from the rest of the collection for a couple of weeks, so an infestation you missed cannot spread while you are still watching for it.
- Keep humidity up where mites are a recurring problem, since dry, warm air is what lets spider mite populations build quickly; this is the opposite of the wet-soil conditions that favour fungus gnats and root rot.
- Check regularly, not just when a plant already looks unwell, since both pests are far easier to treat at the first sign than after they have spread across the whole plant.
FAQ
- How do I know if my plant has spider mites?
- Look for fine pale speckling (stippling) on the leaves and, in a heavier case, delicate webbing between leaves and stems. Tap a leaf over white paper; specks that fall off and crawl are mites.
- How do I know if my plant has mealybugs?
- Look for small white cottony clumps in leaf joints, along stems, or under leaves. Mealybugs do not spin webbing; the white material is a waxy body coating, not silk threads.
- Do spider mites and mealybugs go away on their own?
- No. Both reproduce faster than a plant can outgrow them, so treat as soon as you spot webbing, stippling or cottony clumps, and repeat the treatment on a schedule since one pass rarely kills the eggs.