How can a greenhouse be saved from spider mites? - briefly
Apply integrated pest management: regularly inspect foliage, introduce predatory mites or lady beetles, treat with horticultural or neem oil, keep humidity low, and eliminate heavily infested leaves. Quarantine new plants and maintain sanitation to prevent re‑infestation.
How can a greenhouse be saved from spider mites? - in detail
A vigilant monitoring program is the first line of defense. Inspect foliage daily, focusing on the undersides of leaves where spider mites congregate. Look for stippled discoloration, fine webbing, and tiny moving specks. Early detection allows rapid intervention before populations explode.
Implement cultural practices that disrupt mite development. Reduce plant density to improve air circulation and lower humidity, conditions that favor spider mite reproduction. Maintain temperatures between 65–75 °F (18–24 °C) and avoid excessive heating, which accelerates life cycles. Prune heavily infested shoots and discard them away from the greenhouse.
Adopt physical controls to remove pests instantly. Use a strong jet of water to wash mites off leaves; repeat every 3–5 days during an outbreak. Install fine mesh screens on vents and doors to prevent entry. Sticky traps placed near plant canopies capture wandering adults and provide a visual gauge of infestation levels.
Introduce biological agents as a sustainable control method. Release predatory mites such as Phytoseiulus persimilis or Neoseiulus californicus at a rate of 1–2 predators per square foot. Ensure adequate humidity (≥60 %) for predator survival. Supplement with entomopathogenic fungi like Beauveria bassiana when mite numbers exceed economic thresholds.
Apply chemical measures only when other tactics prove insufficient. Select miticides with low toxicity to beneficial insects, such as neem oil, abamectin, or bifenazate. Follow label rates precisely, rotate active ingredients to delay resistance, and observe pre‑harvest intervals. Conduct a spot test on a single leaf before full‑scale application to verify plant tolerance.
Maintain strict sanitation to eliminate reservoirs. Remove plant debris, fallen leaves, and weeds that can harbor mites. Clean benches, tools, and irrigation equipment with mild detergents. Rotate crops annually and avoid re‑planting susceptible species in the same location without a fallow period.
Integrate these measures into a cohesive management plan: monitor → adjust environment → employ physical removal → release predators → apply miticides as a last resort → enforce sanitation. Consistent execution reduces mite pressure, preserves plant health, and safeguards greenhouse productivity.