What to do with a spider mite?

What to do with a spider mite? - briefly

Apply a strong jet of water or insecticidal soap to kill the spider mite instantly, then introduce predatory mites (e.g., Phytoseiulus persimilis) for ongoing biological control.

What to do with a spider mite? - in detail

Spider mites are tiny arachnids that feed on the undersides of leaves, causing stippling, yellowing, and possible leaf drop. Effective management requires early detection, accurate identification, and a combination of tactics that reduce populations while preserving plant health.

Begin by inspecting plants regularly. Hold a leaf over a white background and look for fine webbing or speckled damage. Use a hand lens to confirm the presence of the mite’s elongated bodies and eight legs.

Control measures fall into three categories:

  • Physical and cultural tactics

    1. Spray leaves with a strong jet of water to dislodge mites and break webs.
    2. Prune heavily infested foliage and discard it away from the garden.
    3. Increase air circulation with fans or by spacing plants more widely.
    4. Keep humidity above 60 % when possible; dry conditions favor mite reproduction.
  • Biological agents

    1. Introduce predatory mites such as Phytoseiulus persimilis or Neoseiulus californicus; release rates depend on infestation severity.
    2. Apply entomopathogenic fungi (e.g., Beauveria bassiana) according to label instructions.
    3. Encourage natural predators by planting flowering species that provide nectar and pollen.
  • Chemical options

    1. Use horticultural oil or neem oil, applying until runoff, to smother mites and disrupt feeding.
    2. Employ acaricides based on active ingredients like abamectin or spirodiclofen for severe outbreaks; rotate modes of action to delay resistance.
    3. Follow pre‑harvest intervals and safety guidelines to avoid residue on edible crops.

Integrate these steps into a monitoring schedule: record mite counts weekly, adjust treatment intensity when thresholds are exceeded, and discontinue applications once populations fall below economic injury levels. Proper disposal of contaminated plant material and thorough cleaning of tools prevent re‑introduction. Combining preventive culture, natural enemies, and targeted chemicals yields sustainable suppression of spider mite infestations.