How to treat a spider mite? - briefly
Apply a miticide such as neem oil or horticultural oil, covering both leaf surfaces and repeating treatment every 5–7 days until mites disappear. Maintain low humidity and introduce predatory mites (e.g., Phytoseiulus persimilis) for biological control.
How to treat a spider mite? - in detail
Spider mites are tiny arachnids that feed on the undersides of leaves, causing stippling, yellowing, and reduced photosynthetic capacity. Early detection relies on inspecting foliage with a magnifying lens; presence of fine webbing confirms an infestation.
Cultural measures reduce population pressure. Maintain optimal watering to prevent plant stress, which makes foliage more attractive to the pest. Adjust fertilization to avoid excess nitrogen, which encourages rapid leaf growth and provides abundant food. Prune heavily infested branches and dispose of them away from the garden.
Mechanical actions interrupt the life cycle. Remove affected leaves by hand or use a strong jet of water to dislodge mites from plant surfaces. Sticky traps placed near the canopy capture wandering adults and provide a visual gauge of infestation levels.
Biological agents offer sustainable control. Introduce predatory insects such as Phytoseiulus persimilis, Neoseiulus californicus, or Amblyseius swirskii; release rates of 10–20 predators per square foot achieve rapid suppression. Apply entomopathogenic fungi (e.g., Beauveria bassiana) according to label instructions; spores penetrate mite cuticles and cause mortality within days.
Chemical options serve as a last resort when other tactics fail. Select products with low toxicity to beneficial organisms, such as horticultural oils, neem oil, or insecticidal soaps. Apply at the recommended concentration, covering both leaf surfaces and undersides. Rotate active ingredients—e.g., abamectin, bifenthrin, or spirotetramat—to delay resistance development. Observe pre‑harvest intervals and protective equipment requirements.
Monitoring continues after treatment. Inspect plants weekly, record mite counts, and adjust management strategies accordingly. Integrating cultural, mechanical, biological, and judicious chemical measures maintains populations below economic thresholds and preserves plant health.