To get rid of aphids on houseplants, isolate the plant, rinse the aphids off under a tap or shower, then treat every few days with an insecticidal soap or neem oil spray until no new aphids appear. Most infestations clear within two to three weeks if you stay consistent.
Aphids are small sap-sucking insects, usually 1 to 3 mm long, and green, black, yellow or pink. They cluster on the softest tissue: new shoots, flower buds and the undersides of young leaves. They breed extremely fast, which is why aphids on houseplants seem to appear overnight, so speed matters more than any single product.
Start by isolating and rinsing
Move the affected plant away from the rest of your collection straight away. Aphids walk and fly to neighbouring plants, and one overlooked shoot can reinfest a whole shelf. Then take the plant to a sink or shower and rinse the aphids off with a firm stream of lukewarm water, tilting the pot so the runoff does not waterlog the roots. This alone removes the bulk of the colony and buys you time.
Treat with insecticidal soap or neem
Rinsing does not catch everything, so follow up with a contact treatment. An insecticidal soap coats and kills the aphids you spray directly, while neem oil both deters feeding and disrupts their breeding cycle over time. Dilute according to the label, and cover the leaf undersides and growing tips thoroughly, which is where aphids hide. A pressure sprayer makes it far easier to get even coverage on a leafy plant.
Whichever you use, treat every three to five days for at least two to three weeks. Aphids reproduce so quickly that a single spray never clears them; you are breaking the breeding cycle, not winning in one go. You will find these and other treatments in our pest and fungal control collection.
Check for ants
If ants are marching up and down the stems, deal with them too. Ants farm aphids for the sugary honeydew they excrete and will actively protect and move them around, so an ant problem keeps an aphid problem alive. Our guide to the most common houseplant pests covers how these problems often travel together.
Wipe away honeydew and sooty mould
Aphids leave a sticky residue called honeydew on leaves and nearby surfaces, and a black fungus called sooty mould often grows on it. Wipe leaves down with a damp cloth as you treat, both to clean off the honeydew and to physically remove more aphids. Try neem leaves steeped as a rinse if you prefer a gentler, plant-based option for wiping down foliage.
Consider biological controls for stubborn cases
If aphids keep returning on a larger plant or a collection, biological controls are worth it. Ladybird larvae (Adalia and other species) and lacewing larvae are voracious aphid predators, and the parasitic wasp Aphidius lays eggs inside aphids, leaving behind papery brown mummies. These are best suited to a greenhouse, conservatory or plant cabinet rather than a single windowsill plant, and you should stop chemical sprays before introducing them, since a spray will kill your predators too. For most single-plant cases indoors, rinsing plus neem is enough.
Keep treating until they are gone, then prevent
Only stop treating once you have gone a full week with no new aphids on the growing tips. Then keep the plant in quarantine a little longer before returning it to the collection. Prevention comes down to habit: inspect new growth weekly, and above all quarantine new arrivals, since shop-bought and gifted plants are the most common way aphids get in. See our advice on quarantining new houseplants and on why pests keep coming back after treatment.