Pests
How to Get Rid of Spider Mites on Houseplants (Full Walkthrough)
A club member askedI just noticed fine webbing between the stems of my calathea, and the leaves have gone pale and speckled, almost dusty looking. I am pretty sure it is spider mites. It sits on a shelf with about a dozen other plants. Can I save it, and how do I keep this from spreading to everything I own?
Take heart, this is winnable. Fine webbing plus pale, stippled leaves is usually spider mites, and calatheas are one of their favorite snacks. Mites thrive in warm, dry air, which is why they so often explode in winter next to a heat vent. They pierce individual leaf cells and drain them, which is what makes those tiny pale dots.
The battle plan
- Quarantine first. Move the plant well away from the shelf. Mites travel on drafts, sleeves, and curious pets.
- Shower the whole plant with lukewarm water, tops and undersides of every leaf. This knocks off most of the population before you spray a thing.
- Spray every leaf surface with insecticidal soap or horticultural oil, undersides especially. That is where they live and lay their eggs.
- Repeat every five to seven days for three or four rounds. Sprays usually miss the eggs, so you are breaking the hatch cycle, not winning in one blow.
- Raise the humidity. Mites hate moist air, and your calathea will throw a small party.
- Inspect the neighbors. Check leaf undersides across the whole shelf with a bright light, and treat anything suspicious the same way.
What to expect
Stippled leaves will not heal; that damage is a scar, not an active problem. Judge progress by new growth instead. If new leaves come in clean over the next two to three weeks, you are winning. Keep the patient quarantined for a full month before it rejoins the shelf, then do a quick weekly leaf check as insurance.
Start here: why is my plant dying? — the four checks and the five things that kill nearly every houseplant.
Answers are written by AI and safety-checked by code before they post — no feeding doses, no medical advice, anything toxic to cats or dogs flagged. No human reads a question or an answer before it goes up, so treat this as good, careful guidance rather than professional or veterinary advice. If the plant is precious, or you suspect a spreading pest or disease, get human eyes on it too.