How should cucumbers be treated for mites in a polycarbonate greenhouse? - briefly
Use a registered miticide (e.g., abamectin, neem oil, or spinosad) applied to all foliage, especially leaf undersides, at label‑recommended concentrations. Combine chemical treatment with weekly inspections and release of predatory mites to keep populations low.
How should cucumbers be treated for mites in a polycarbonate greenhouse? - in detail
Effective control of cucumber mite infestations in a polycarbonate greenhouse requires an integrated approach that combines cultural, biological, and chemical tactics.
First, maintain optimal environmental conditions. Keep temperature between 20‑25 °C and relative humidity around 60 % to discourage mite reproduction. Ensure adequate ventilation to reduce leaf surface humidity, which limits mite colonization.
Second, implement strict sanitation. Remove all plant debris, trim heavily infested leaves, and sterilize tools with a 10 % bleach solution. Replace any heavily damaged vines with clean stock.
Third, introduce natural enemies. Release predatory phytoseiid mites such as Phytoseiulus persimilis or Neoseiulus californicus at a rate of 10–20 predators per square meter. Monitor predator establishment weekly and supplement releases when predator counts drop below threshold levels.
Fourth, apply acaricides judiciously. Use products labeled for greenhouse cucumbers, rotating modes of action to prevent resistance. A typical schedule might include:
- Early detection – apply a miticide with a contact action (e.g., sulfur) at 2 g m⁻².
- Two weeks later – use an oil‑based product (e.g., neem oil) at 5 ml L⁻¹.
- After another 10–14 days – switch to a systemic acaricide (e.g., abamectin) at 0.1 mg L⁻¹, observing pre‑harvest interval requirements.
Always follow label instructions regarding dosage, application timing, and safety intervals.
Fifth, conduct regular scouting. Inspect the underside of leaves twice weekly, counting mites per leaf. Initiate treatment when populations exceed 5 mites per leaf or when damage reaches 10 % of leaf area.
Finally, document all actions. Record environmental parameters, scouting data, predator releases, and pesticide applications. Analyze trends to refine the program and maintain long‑term control.