How to treat a greenhouse for mites? - briefly
Inspect the greenhouse, remove heavily infested plants, and clean surfaces with a strong soap solution. Then apply a registered miticide such as sulfur or neem oil, increase ventilation, and keep humidity low to suppress mite populations.
How to treat a greenhouse for mites? - in detail
Mite infestations in greenhouse environments require a systematic approach that combines early detection, cultural adjustments, biological agents, and, when necessary, chemical interventions.
Accurate identification is the first step. Use a magnifying lens or a digital microscope to examine leaf undersides, flower buds, and soil surface. Look for tiny, moving specks (typically 0.2–0.5 mm) and fine webbing. Record infestation levels on a scale of 0–5 to track progress.
Cultural measures reduce habitat suitability:
- Maintain relative humidity between 60 % and 70 %; low humidity discourages spider‑mite reproduction.
- Regulate temperature to stay within the optimal range for the cultivated species, avoiding excess heat that accelerates mite life cycles.
- Space plants to improve air circulation and reduce leaf wetness.
- Remove plant debris, fallen leaves, and infested material promptly.
- Rotate crops and avoid planting the same species in the same location for more than two consecutive cycles.
Mechanical tactics provide immediate relief:
- Spray foliage with a strong jet of water to dislodge mites; repeat every 3–4 days until populations drop.
- Install yellow sticky traps at canopy level; replace weekly and count captured mites to gauge population trends.
Biological control agents offer sustainable suppression:
- Release predatory phytoseiid mites (e.g., Phytoseiulus persimilis or Neoseiulus californicus) at a rate of 1 predator per 10 cm² of leaf area.
- Introduce predatory insects such as Amblyseius swirskii for broader pest coverage.
- Ensure adequate humidity (≥70 %) to support predator activity and reproduction.
Chemical options should be reserved for severe outbreaks and applied according to label instructions:
- Use neem‑oil formulations (2–3 % concentration) as a contact insecticide; repeat after 7 days.
- Apply horticultural oil (e.g., mineral oil) at 1–2 % to suffocate mites; avoid temperatures above 30 °C to prevent phytotoxicity.
- Select acaricides with low persistence (e.g., spinosad) to minimize residue buildup; rotate active ingredients to delay resistance.
Integrated pest management (IPM) cycles incorporate monitoring, threshold decision‑making, and timely intervention. Set action thresholds (e.g., >5 mites per leaf) and follow the outlined steps without delay. Consistent record‑keeping and adherence to preventive cultural practices will keep mite populations below damaging levels and preserve greenhouse productivity.