How should I treat spider mite?

How should I treat spider mite? - briefly

Use horticultural oil or neem oil spray together with frequent water jets to knock pests off the foliage, and add predatory mites (e.g., Phytoseiulus persimilis) if the problem continues. Keep humidity low and limit nitrogen fertilizer to reduce mite reproduction.

How should I treat spider mite? - in detail

Spider mites thrive in hot, dry conditions and reproduce rapidly on the undersides of leaves. Early detection relies on visual inspection: look for stippled foliage, fine webbing, and tiny moving specks. Confirm presence by shaking a leaf over white paper; mites will fall and become visible.

Control strategies combine cultural, mechanical, biological, and chemical measures.

• Cultural practices

  • Increase humidity to 50‑70 % by misting or using a humidifier.
  • Reduce temperature extremes; keep greenhouse or indoor environments below 80 °F (27 °C) when possible.
  • Remove heavily infested leaves and dispose of them away from the growing area.
  • Space plants to improve air circulation and limit microclimates that favor mites.

• Mechanical removal

  • Wash foliage with a strong jet of water, targeting the leaf underside.
  • Apply a fine‑toothed brush or cotton swab dipped in soapy water to dislodge mites.
  • Use sticky traps placed near plants to monitor adult populations.

• Biological agents

  • Introduce predatory mites such as Phytoseiulus persimilis or Neoseiulus californicus; release rates of 5‑10 predators per square foot are effective for moderate infestations.
  • Apply entomopathogenic fungi (e.g., Beauveria bassiana) according to label instructions for supplemental control.

• Chemical options

  • Use horticultural oil or neem oil at 1‑2 % concentration; spray thoroughly, covering both leaf surfaces, and repeat every 7‑10 days until populations decline.
  • Select miticides with low toxicity to beneficial insects, such as abamectin or spirotetramat; follow label dosage and pre‑harvest intervals precisely.
  • Rotate active ingredients to prevent resistance buildup; avoid repeated use of the same mode of action.

Monitoring continues after treatment. Count mites per leaf area weekly; when numbers fall below 2 mites per cm², reduce intervention frequency but maintain preventive practices. Maintaining optimal environmental conditions and regular scouting prevents re‑infestation and protects plant health.