My indoor chilli plants have whitefly. I’ve tried putting grit on top of the compost, washing the leaves and spraying with a soap solution. What should I do?
Whitefly and aphids are fond of indoor chillies. Such a comfy life: central heating, no predators and regularly watered, tender plants. It’s easy to get these pests confused, so check what you have – whitefly will fly off if you shake the plant, whereas aphids cling.
Grit on the compost won’t do anything for either pest, although it can prevent fungus gnats, and looks attractive. Washing the plants can dislodge pests, but the washing-up liquid trick flouts EU rules. The legal version is horticultural soft soap; for it to work you’d have to spray regularly.
The best option for whitefly is to introduce Encarsia, a tiny parasitic biological control. It’s effective, although not cheap. Or boost the plants’ own defences by stimulating growth: Garlic Wonder and SB Plant invigorator are popular choices.
If these are too expensive, take a gamble: put the plants outside the back door when you know there won’t be a hard frost. The pests won’t take a chilly night well, but healthy plants will pull through.
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