What should be done about spider mites? - briefly
Apply a miticide or release natural predators such as predatory mites, and keep humidity low to reduce spider‑mite proliferation. Regularly inspect plants and remove heavily infested foliage to prevent further outbreak.
What should be done about spider mites? - in detail
Spider mites (e.g., «Tetranychus urticae») feed on plant tissue, causing stippling, yellowing, and reduced photosynthetic capacity. Rapid population growth under warm, dry conditions makes early intervention essential.
Cultural measures reduce habitat suitability. Remove infested foliage, keep plant canopies open to improve air circulation, and apply a fine stream of water to dislodge mites from leaf surfaces. Mulch and debris elimination prevent sheltering sites.
Biological agents provide sustainable suppression. Predatory mites such as Phytoseiulus persimilis, Neoseiulus californicus, and Amblyseius swirskii consume large numbers of spider mites. Release rates should match infestation severity; repeated applications maintain predator populations. Supplementary releases of lady beetles (e.g., Stethorus punctillum) and lacewings can enhance control in greenhouse environments.
Chemical options include miticides with distinct modes of action to avoid resistance buildup. Early‑season applications of neem oil or insecticidal soaps offer contact toxicity with minimal residual effects. For severe outbreaks, rotate systemic acaricides (e.g., abamectin, bifenazate) according to label‑specified intervals. Record product use to track resistance trends.
Integrated management follows a systematic cycle: monitor leaf undersides weekly with a hand lens, record mite counts, compare against established economic thresholds, and select the least disruptive control method that meets the threshold. Combine cultural, biological, and chemical tactics to maintain mite populations below damaging levels while preserving beneficial organisms.