How to eradicate spider mites? - briefly
Apply a miticide or release predatory insects such as lady beetles, while keeping foliage dry and regularly washing leaves with a mild soap solution. Complement chemical treatment with cultural measures like pruning heavily infested parts and maintaining adequate ventilation to prevent recurrence.
How to eradicate spider mites? - in detail
Spider mites thrive in hot, dry conditions and reproduce rapidly, so effective control requires a combination of cultural, biological, and chemical measures.
First, modify the growing environment. Keep humidity above 60 % by misting foliage several times a day or using a humidifier. Water plants at the soil level to avoid wetting leaves, then allow the canopy to dry slowly; this reduces the micro‑climate that favors mite development. Remove heavily infested leaves and discard them away from the garden to eliminate breeding sites.
Second, employ natural enemies. Predatory mites such as Phytoseiulus persimilis and Neoseiulus californicus consume large numbers of spider mites and can be released from commercial suppliers. Ladybird beetle larvae and predatory thrips also contribute to suppression. For optimal results, introduce these agents when mite populations are low and provide a pollen source (e.g., Typha pollen) to sustain them.
Third, apply horticultural oils and soaps. Dilute neem oil, horticultural oil, or insecticidal soap to the manufacturer’s recommended concentration and spray thoroughly, covering the undersides of leaves where mites reside. Repeat applications every 5–7 days until no mobile stages are observed, then discontinue to prevent resistance buildup.
Fourth, consider selective miticides only if other tactics fail. Products containing abamectin, spiromesifen, or bifenazate are effective against all life stages but must be rotated with different chemistries to avoid resistance. Follow label instructions precisely, observe pre‑harvest intervals, and protect beneficial insects by applying during low activity periods (early morning or late evening).
Finally, monitor continuously. Use a 10 × 10 cm white paper to tap foliage; count the number of motile mites per leaf. A threshold of 10 mites per leaf typically signals the need for intervention. Record observations weekly to track population trends and adjust tactics accordingly.
By integrating environmental adjustments, biological control agents, safe spray compounds, and, when necessary, carefully managed chemicals, a persistent spider mite problem can be brought under control and prevented from re‑establishing.