---
title: "Houseplant Pest Identifier: Small White Bugs | Mend Petal"
description: "Small white bugs, webbing or tiny flies on your plant? A picture key names the pest, gives its treatment ladder and builds a 7-day re-check calendar."
url: https://mendpetal.me/houseplant-pest-identifier/
---

Pest identifier

# Small white bugs on your plant? Name the pest

Small white bugs on a houseplant are usually mealybugs (cottony blobs in the leaf joints), whiteflies (tiny white insects that fly up when you brush the plant) or, if the specks crawl on fine webbing, spider mites. Pick what you see below: the key names the pest, gives the treatment ladder from water and wiping up to soap or oil, and sets a re-check every 7 days.

## Small white bugs: the usual suspects

Three pests account for most “little white bugs”. They look alike at a glance but behave very differently, and the treatment differs too.

| Pest | What you see | Where | Moves? |
| --- | --- | --- | --- |
| Mealybugs | White, cottony or waxy blobs, up to about 4 mm (RHS) | Leaf joints, along veins, under leaves | Barely |
| Whiteflies | Tiny white winged insects, about 1.5 mm (RHS), and flat scale-like young | Undersides of leaves | Adults fly up when the plant is touched |
| Spider mites | Moving dots under 0.5 mm, pale speckling, fine webbing | Undersides of leaves, growing tips | Crawl; easy to see with a 10× lens |

White cast skins on new shoots belong to aphids, which shed them as they grow (UC IPM), and the yellow-orange crawlers of scale insects are tiny enough to need a lens.

## How to look: a lens and a sheet of white paper

Hold white paper under a stem and tap it: specks like dust or pepper that crawl away are spider mites (Iowa State, Missouri Botanical Garden). A 10× hand lens shows small pests and their young under the leaves (Clemson, UC IPM).

Pests hide on the undersides of leaves, in leaf joints and on new growth, so turn leaves over rather than looking down on the plant. Shaking a shoot over white paper works for thrips too, and you may spot sticky honeydew before the insects that make it (Penn State).

## The treatment ladder

UC IPM’s advice for houseplants climbs from the gentlest step to stronger ones, and only goes up a rung when the one below has not worked.

1. **By hand and with water.** Isolate the plant, wash pests off, wipe or pick them off, and cut away infested parts. For mealybugs, a cotton swab dipped in rubbing alcohol (70% or weaker) works on a few at a time; test it on a small part of the plant a day or two first. For fungus gnats, let the compost surface dry and use yellow sticky cards.
2. **Insecticidal soap or horticultural oil.** These work only on pests they touch, so the spray has to reach the undersides of the leaves, and repeats are often needed. Test on a few leaves first, and UC IPM warns against spraying water-stressed plants or above 32°C (90°F).
3. **Other options.** Bti drenches for fungus gnat larvae, and for some pests a systemic product as a last resort, with the caveats in each pest report. Sometimes the right last step is to throw the plant out before the pests spread.

Use only products labelled for indoor use on that plant and pest, and follow the label: UC IPM’s warning page puts it as “the label is the law”. Its statement on homemade pesticides says they should not be recommended, dish-soap recipes included.

## Why a re-check every 7 days

Sprays and wiping miss eggs and hidden young, which hatch over the following days. Spider mites go from egg to adult in about two weeks at 24°C (75°F) indoors, and aphids can be producing young of their own 7 to 8 days after birth (UC IPM). So treatment is a series, not a single event. UC IPM advises watching new plants weekly, and its mealybug guidance repeats treatment every week until they are gone; Clemson says spider mites often need spraying once a week for several weeks. A few pests need a faster rhythm: UC IPM repeats Bti for fungus gnats about every five days, and checks for aphids at least twice a week while plants are growing fast.

The schedule in the tool lists a check every 7 days from the date you choose. Download it as a standard .ics calendar file, which calendar apps such as Apple Calendar, Google Calendar and Outlook can import, or print the table and keep it near the plants.

## New plants and holiday gifts

November and December bring new plants into the house: poinsettias, holiday cacti, amaryllis, and plants that summered outdoors coming back in. UC IPM advises inspecting plants before you buy them, roots included, and re-inspecting plants returning from outdoors. Clemson suggests keeping new plants apart for six weeks and examining them about once a week; Penn State suggests about three weeks.

Downloading a free pest guide?

Plant shops and growers often offer free care e-books and pest guides in exchange for an email address. A temporary inbox from [CleanTempMail](https://cleantempmail.com/) needs no sign-up and empties itself after three days, so it can receive the download link without the newsletters that follow. Download the guide straight away, and use your real address for plant orders and deliveries.

## Common mistakes

- **Spraying before you are sure.** Name the pest first; for spider mites UC IPM says to always check mite numbers before treating.
- **One treatment and done.** Eggs and hidden stages survive, so plan for several rounds.
- **Spraying only the tops of the leaves.** Soap and oil must touch the pests underneath.
- **Leaving the plant with the others.** Isolate it and wash your hands after handling it (UC IPM).

General information from UC IPM, Clemson, the RHS and Penn State Extension, not professional advice. Pesticide rules differ between countries and states.

## Frequently asked questions

**What are the small white bugs on my plant?**

Most often mealybugs (cottony blobs in leaf joints that barely move) or whiteflies (tiny white insects that fly up when the plant is touched). Moving specks on fine webbing are spider mites.

**What are the tiny black flies in my houseplant soil?**

Fungus gnats. They breed in compost that stays moist, so let the surface dry between waterings and catch the adults on yellow sticky cards. UC IPM lists Bti drenches, repeated about every five days, for the larvae.

**How do I get rid of spider mites on a houseplant?**

Isolate it, spray the leaves forcefully with water, undersides included, and repeat weekly for several weeks (Clemson). UC IPM keeps insecticidal soap or horticultural oil as a last resort indoors and advises avoiding broad-spectrum insecticides.

**Is rubbing alcohol safe for mealybugs?**

UC IPM suggests dabbing them with 70% or weaker rubbing alcohol on a cotton swab, after testing it on a small part of the plant one or two days first. Alcohol is flammable and is not a registered pesticide.

**How often should I check a plant for pests?**

Weekly while you are treating it or while it is new to the house (UC IPM, Clemson); then UC IPM suggests monthly once several weeks pass without pests.

## Sources

All opened and checked on 3 November 2026. UC IPM’s Pest Notes are the main source; the RHS and Clemson fill in sizes in millimetres and life cycles.

1. [Pest Notes: Houseplant Problems (Publication 74172)](https://ipm.ucanr.edu/home-and-landscape/houseplant-problems/). UC Statewide IPM Program, University of California, updated August 2020.
2. [Pest Notes: Spider Mites (Publication 7405)](https://ipm.ucanr.edu/home-and-landscape/spider-mites/). UC Statewide IPM Program, University of California, updated December 2011.
3. [Pest Notes: Mealybugs (Publication 74174)](https://ipm.ucanr.edu/home-and-landscape/mealybugs/). UC Statewide IPM Program, University of California, updated March 2016.
4. [Pest Notes: Scales (Publication 7408)](https://ipm.ucanr.edu/home-and-landscape/scales/). UC Statewide IPM Program, University of California, updated September 2014.
5. [Pest Notes: Fungus Gnats (Publication 7448)](https://ipm.ucanr.edu/home-and-landscape/fungus-gnats/). UC Statewide IPM Program, University of California, updated August 2013.
6. [Pest Notes: Thrips (Publication 7429)](https://ipm.ucanr.edu/home-and-landscape/thrips/). UC Statewide IPM Program, University of California, updated May 2014.
7. [Pest Notes: Aphids (Publication 7404)](https://ipm.ucanr.edu/home-and-landscape/aphids/). UC Statewide IPM Program, University of California, updated July 2013.
8. [Pest Notes: Whiteflies (Publication 7401)](https://ipm.ucanr.edu/home-and-landscape/whiteflies/). UC Statewide IPM Program, University of California, updated September 2015.
9. [Warning on the Use of Pesticides](https://ipm.ucanr.edu/home-and-landscape/warning-on-the-use-of-pesticides/). UC Statewide IPM Program, University of California.
10. [UC IPM Statement on Homemade Pesticides](https://ucanr.edu/blog/coordinator-news/article/uc-ipm-statement-homemade-pesticides). UC Statewide IPM Program (UC ANR), 30 July 2024.
11. [Common Houseplant Insects & Related Pests (HGIC 2252)](https://hgic.clemson.edu/factsheet/common-houseplant-insects-related-pests/). Clemson Cooperative Extension, Home & Garden Information Center, updated 10 September 2021.
12. [Insecticidal Soaps for Garden Pest Control (HGIC 2771)](https://hgic.clemson.edu/factsheet/insecticidal-soaps-for-garden-pest-control/). Clemson Cooperative Extension, Home & Garden Information Center, updated 30 July 2021.
13. [Glasshouse red spider mite](https://www.rhs.org.uk/biodiversity/glasshouse-red-spider-mite). Royal Horticultural Society.
14. [Mealybug (glasshouse)](https://www.rhs.org.uk/biodiversity/mealybug). Royal Horticultural Society.
15. [Scale insects](https://www.rhs.org.uk/biodiversity/scale-insects). Royal Horticultural Society.
16. [Fungus gnats](https://www.rhs.org.uk/biodiversity/fungus-gnats). Royal Horticultural Society.
17. [Thrips on garden plants](https://www.rhs.org.uk/biodiversity/thrips). Royal Horticultural Society.
18. [Glasshouse whitefly](https://www.rhs.org.uk/biodiversity/glasshouse-whitefly). Royal Horticultural Society.
19. [Aphids](https://www.rhs.org.uk/biodiversity/aphids). Royal Horticultural Society.
20. [Pest and Disease Problems of Indoor Plants](https://extension.psu.edu/pest-and-disease-problems-of-indoor-plants). Penn State Extension, updated 12 October 2026.