Spider Mites on Houseplants: How to Spot and Get Rid of Them

[MAIN PHOTO (preview): fine spider mite webbing between houseplant leaves]

Spider mites are the most common houseplant pest during the heating season. They are almost invisible to the naked eye, so most owners only notice the damage: dull, dusty-looking leaves covered in tiny pale specks and fine webbing on the stems. Mites multiply within days, so act straight away. Here is how to identify them, how to treat your plants and how to stop them coming back, based on Google data and UFL’s own observations.

What spider mites look like

It is not an insect but a tiny arachnid (usually Tetranychus urticae), 0.3–0.5 mm long. Adults have eight legs and an oval body that is yellowish-green, orange or red; overwintering females often turn red. The round, translucent eggs sit on leaf undersides. Mites live in colonies, suck the sap out of leaf cells and spin webbing that they use to move between stems and plants.

The simplest test: tap a branch over a sheet of white paper. If tiny moving “specks of dust” appear, they are mites. With a 10× hand lens they are easy to see.

[фото: spider mite magnified on a leaf]

[фото: white paper test for detecting mites]

Signs of spider mites on houseplants

• Tiny pale or yellow specks on leaves — feeding punctures; over time the leaf turns mottled and greyish-dull.
• Fine webbing in leaf axils, between leaf stalks and over shoot tips.
• Leaves yellow, curl, dry out and drop; new growth is small and distorted.
• Moving “dust” and specks of shed skins on leaf undersides.
• Flower buds dry up before opening.

Speckling can also come from thrips or sunscorch, and yellowing from watering mistakes. Compare symptoms in our guide to houseplant problems.

[фото: leaf with tiny pale specks from spider mites]

[фото: webbing over a houseplant shoot tip]

Why mites appear and which plants are at risk

Mites love warmth and dry air: at 25–30 °C and humidity below 50 % a new generation develops in about a week, and a female lays up to a hundred eggs. That is why outbreaks peak in winter near radiators and in summer on sunny windowsills — see our tips on houseplant care in the heating season. Mites arrive on new plants, cut flowers, soil, clothing or through an open window, then spread to neighbouring plants along their webbing.

The most vulnerable are figs (including the fiddle leaf fig), potted roses, hydrangeas, croton, schefflera, dracaenas, alocasia, citrus, ivy and orchids. Tough-leaved succulents and plants with hairy leaves are attacked less often but are not immune.

[фото: ficus with yellowing leaves damaged by spider mites]

How to get rid of spider mites: step by step

1. Isolate the plant and inspect every pot nearby — mites spread fast.
2. Remove the worst leaves and webbed shoots and bin them in a sealed bag.
3. Shower the plant with warm water (about 40 °C), especially leaf undersides, with the soil covered by film.
4. Wipe the leaves with soapy water (plain or potassium soap) and rinse after 15–30 minutes. Tough leaves of figs and orchids can be wiped with cotton pads dampened with 30–40 % alcohol — test on one leaf first.
5. Apply a miticide for heavy infestations: spray the whole plant, the windowsill and the pot. Afterwards you can cover the plant with a clear bag for 1–2 days, as high humidity suppresses mites.
6. Repeat 3–4 times at 5–7 day intervals. Most products do not kill eggs, so a single treatment almost never works.
7. Return the plant to its spot only after two inspections in a row show no specks or webbing.

[фото: showering a houseplant with warm water against mites]

[фото: wiping an orchid leaf with a cotton pad]

Miticides

Mites are not insects, so ordinary insecticides are useless against them. You need a miticide or a combined insecticide-miticide:

Mites quickly become resistant to a single active ingredient, so rotate products from different groups if outbreaks recur. Follow the label for dose and number of treatments, wear gloves, ventilate the room and keep children and pets away.

[фото: spraying a houseplant with a miticide while wearing gloves]

Home remedies: what actually works

Home remedies suit early infestations or as a supplement to treatment:

• Soapy water washes off mites and webbing; repeat every 5–7 days.
• Garlic infusion (about 50 g crushed garlic per litre of water, steeped for a day) and onion skin infusion repel mites but will not wipe out a colony.
• Warm shower plus a bag — high humidity slows breeding.
• Predatory mites (Phytoseiulus) — a biological option for conservatories and large collections.

If specks and webbing return after 2–3 rounds, switch to a miticide.

Mites on orchids, figs and roses

• Orchids show silvery patches and tiny punctures, and flowers fade quickly. Wipe leaves with alcohol pads, do not let water sit in the crown after a shower and cover the bark before treatment.
• Figs drop leaves first. Wash big tough leaves with a sponge on both sides and spray a tub-grown tree in the bath.
• Potted roses are a mite favourite: keep them cool, mist regularly and check young shoots.

[фото: phalaenopsis orchid showing spider mite damage]

Prevention

• Keep humidity at 50–60 %, especially in the heating season: a humidifier or trays of wet clay pebbles.
• Quarantine new plants for 2 weeks and inspect them carefully.
• Shower the leaves or wipe them with a damp sponge every 1–2 weeks.
• Check leaf undersides weekly, especially on figs and roses.
• Keep pots away from radiators and avoid excess nitrogen — soft, lush growth attracts mites.

Healthy plants are attacked less often, so avoid common houseplant care mistakes.

[фото: humidifier next to houseplants]

Are spider mites dangerous to people?

No. Spider mites feed only on plant sap, do not bite people or pets and do not carry disease. They are unrelated to the ticks found in long grass. The only real risk comes from chemical treatments, so follow safety precautions.

FAQ

How many treatments does it take?

Usually 3–4, 5–7 days apart, so you kill the mites that hatch from eggs after each round.

Can a shower alone get rid of mites?

Sometimes, at an early stage, if you wash the plant weekly and raise humidity. A large colony needs a miticide.

Does Actara work on spider mites?

No. Actara and Confidor target insects, and mites are arachnids. Use a miticide, for example one based on aversectin or abamectin.

Why do mites keep coming back?

Eggs that survived treatment, warm dry air, or untreated neighbouring plants. Treat every plant nearby and the windowsill too.

Is it the same mite as on cucumbers?

Yes, it is the same species and the principles are similar, but vegetable gardens need products with a pre-harvest interval.

Author: Maria Svitlovir

Graduated from Taras Shevchenko National University of Kyiv, Institute of Biology and Medicine (2001). BSc in Biology, MSc in Horticulture. Writes about plants, works at a garden centre selecting and repotting plants, and contributes to plant reference guides.

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