Plant Pests

The most common houseplant pests are fungus gnats, spider mites, mealybugs, thrips, and scale insects. Each one hides differently, causes different damage, and responds to a different first treatment. The fastest path to solving any of them is figuring out where the problem is showing up first, not reaching for a product. If nothing is moving and the pattern looks more like spreading spots, mildew, rot, or wilt, switch to the houseplant diseases guide before treating for insects. ...

By KnowYourPlant Editorial Team, updated June 24, 2026. This version keeps the guide aligned with extension and IPM guidance reviewed for the June 18, 2026 evidence refresh. Start Here if You Need the Gnats Down Fast If you are standing over the pot right now and just want the first three moves, do these before you try anything fancy: Put a yellow sticky trap in every suspect pot so you can see which container is actually feeding the outbreak. Let the top 1 to 2 inches of mix dry as much as the plant safely allows, then empty every saucer, cachepot, or reservoir holding leftover water. If adults return after the next watering, add a labeled larval treatment such as BTI or beneficial nematodes and focus on the wettest source pots first. If the plant is a seedling, fresh cutting, or already recovering from root stress, keep the dry-down gentler and lean harder on monitoring plus larval control. ...

You notice a faint dustiness on the leaves. Maybe some tiny yellow speckles, or a leaf that looks a little washed out. You lean in closer and see the faintest threads of webbing in the crook where the stem meets a leaf. That’s when you know: spider mites have found your plant. Knowing how to get rid of spider mites is one of the most useful things you can learn as a plant person, because these pests move fast and they don’t announce themselves loudly. The good news is that if you catch them early, they’re very manageable. And even if the infestation has gotten ahead of you, there’s still a clear path back. ...