How do you treat a spider mite infestation? - briefly
Apply horticultural oil or neem oil, introduce predatory mites such as Phytoseiulus persimilis, keep leaf surface humidity above 50 %, and prune heavily infested foliage.
How do you treat a spider mite infestation? - in detail
Spider mites thrive in hot, dry conditions and reproduce rapidly, so early detection and swift action are essential. Examine the undersides of leaves for tiny, moving specks and stippled discoloration; a fine webbing often indicates a severe outbreak.
Effective management combines cultural, mechanical, biological, and chemical methods.
- Reduce humidity stress by misting foliage regularly and increasing ambient moisture.
- Eliminate excess nitrogen fertilization; high nitrogen levels promote rapid mite population growth.
- Prune heavily infested shoots and discard them away from the garden to remove breeding sites.
- Wash plants with a strong jet of water, targeting the leaf undersides, to dislodge mites and their webs.
Biological controls provide long‑term suppression. Introduce predatory mites such as Phytoseiulus persimilis or Neoseiulus californicus; release rates of 10–20 predators per square foot establish a self‑sustaining population. Preserve habitats for native predators by maintaining ground cover and avoiding broad‑spectrum insecticides.
When cultural and biological options are insufficient, selective acaricides may be applied. Choose products based on active ingredients—abamectin, spirodiclofen, or neem oil—and follow label‑specified intervals to prevent resistance. Rotate chemicals with different modes of action; a minimum 7‑day gap between applications reduces the risk of mite adaptation.
Preventive practices sustain plant health and deter future invasions.
- Monitor temperature and humidity, keeping daytime leaf temperatures below 30 °C when possible.
- Apply a thin layer of horticultural oil early in the season; the oil suffocates emerging mite eggs without harming the plant.
- Maintain clean tools and avoid moving infested plant material between locations.
Consistent scouting, combined with the integrated tactics outlined above, curtails spider mite populations and protects foliage from extensive damage.