How should spider mites on indoor plants be treated? - briefly
Wash the plant thoroughly with a strong jet of water to dislodge mites, then treat with a suitable miticide such as neem oil or horticultural oil, repeating the application every 7–10 days until the pests are gone. Keep humidity low and inspect regularly to avoid reinfestation.
How should spider mites on indoor plants be treated? - in detail
Spider mite infestations on indoor foliage require prompt, systematic action to prevent rapid population growth and leaf damage. Effective control combines cultural, mechanical, biological, and chemical measures.
First, isolate the affected plant to stop spread. Reduce ambient humidity to 60 % or lower, as dry conditions favor mite reproduction. Increase air circulation with a fan for at least 30 minutes daily.
Second, remove visible mites and eggs by washing the plant. Use a gentle stream of lukewarm water or a spray of soapy solution (1 tsp mild liquid soap per liter of water). Thoroughly cover the undersides of leaves, where mites congregate. Repeat the rinse every 3–5 days for two weeks.
Third, introduce natural predators if the infestation is moderate to severe. Predatory mites such as Phytoseiulus persimilis or Neoseiulus californicus can be released according to label instructions. Maintain a temperature of 20–25 °C and avoid broad‑spectrum insecticides that would harm the biocontrol agents.
Fourth, apply horticultural oil or neem oil if biological control is insufficient. Mix oil to a concentration of 1–2 % (v/v) and spray until runoff, ensuring coverage of leaf undersides. Apply in the early morning or late evening to reduce phototoxicity. Reapply every 7–10 days until no mites are observed.
Fifth, reserve synthetic acaricides for extreme cases. Choose products labeled for indoor use, such as abamectin or spirotetramat, and follow the manufacturer’s dosage and safety guidelines. Limit applications to the minimum effective number and rotate modes of action to delay resistance.
Finally, monitor the plant weekly for at least one month after treatment. Look for new webbing, stippling, or yellowing. Maintain optimal watering, adequate lighting, and regular cleaning to keep the environment unfavorable for future outbreaks.