How to get rid of spider mite on cucumbers in a greenhouse? - briefly
Apply non‑chemical controls—lower humidity, release «predatory mites», and spray «neem‑oil solution» every 5–7 days while monitoring with sticky traps. If the population remains high, switch to a registered synthetic acaricide for greenhouse cucumbers, observing label dosages and pre‑harvest intervals.
How to get rid of spider mite on cucumbers in a greenhouse? - in detail
Spider mites (Tetranychidae) thrive on cucumber vines when temperature and humidity in a greenhouse create favorable conditions. Early detection relies on visual inspection of leaf undersides for stippled discoloration, fine webbing, and moving specks. A magnifying lens or hand‑held microscope improves accuracy.
Cultural measures reduce population buildup. Maintain leaf temperature below 30 °C by adjusting ventilation and shading. Keep relative humidity around 60 % to discourage mite reproduction. Remove wilted or heavily infested foliage promptly; dispose of material away from the crop area. Rotate cucumber varieties with those less attractive to mites and alternate planting locations each season to interrupt life cycles.
Biological agents offer sustainable control. Introduce predatory mites such as Phytoseiulus persimilis, Neoseiulus californicus, or Amblyseius swirskii at a rate of 10–20 predators per square meter. Ensure a pollen source (e.g., pollen from Brassica spp.) to sustain predator populations during low prey periods. Apply entomopathogenic fungi (Beauveria bassiana) according to label instructions; fungal spores penetrate mite cuticle and reduce numbers within 5–7 days.
Chemical options serve as a last resort when thresholds are exceeded. Select miticidal products with low phytotoxicity to cucumber and minimal residue, such as sulfur, neem oil, or spinosad. Rotate active ingredients to prevent resistance: follow a schedule of at least 14 days between applications of the same mode of action. Observe pre‑harvest interval (PHI) and comply with local residue regulations.
Monitoring continues throughout the production cycle. Use sticky traps placed at canopy height to gauge mite activity and predator presence. Record weekly counts and compare against economic thresholds (e.g., 5 mites per leaf). Adjust management tactics promptly based on data.
Integrated approach—combining environmental regulation, sanitation, biological agents, and judicious chemical use—provides effective, durable suppression of spider mite infestations on cucumber crops grown under greenhouse conditions.