What helps control spider mites on cucumbers in a greenhouse? - briefly
Introduce predatory mites such as Phytoseiulus persimilis or Neoseiulus californicus, maintain high humidity (≥60 %), and apply horticultural or neem oil sprays to suppress spider‑mite populations; rotate with low‑toxicity acaricides only when thresholds are exceeded. Regular scouting and sanitation complete the management strategy.
What helps control spider mites on cucumbers in a greenhouse? - in detail
Spider mites rapidly colonize cucumber crops in protected environments, causing leaf stippling, webbing, and reduced photosynthetic capacity. Prompt detection and a multi‑pronged strategy are essential to keep infestations below economic thresholds.
Cultural measures reduce initial populations and limit spread. Remove plant debris and weeds that can harbor mites. Conduct weekly inspections with a hand lens; count mites on the underside of several leaves to establish baseline levels. Use cucumber varieties with documented tolerance to mite damage, and rotate crops with non‑cucurbit hosts to disrupt the pest’s life cycle.
Biological agents provide continuous suppression. Introduce predatory mites such as Phytoseiulus persimilis, Neoseiulus californicus, or Amblyseius swirskii at a rate of 10–20 predators per plant when mite numbers exceed 5 mites per leaf. Maintain a supplemental food source (e.g., pollen or yeast) to sustain predator populations during low prey periods. Release additional generations every 7–10 days if mite densities rise.
Chemical controls are effective when applied selectively. Use miticides with different modes of action—abamectin, bifenazate, or spiromesifen—according to label recommendations. Rotate products every 2–3 applications to prevent resistance. Apply the lowest effective concentration, targeting the leaf underside, and observe a pre‑harvest interval before marketable fruit is harvested.
Environmental adjustments create unfavorable conditions for the pest. Keep relative humidity above 60 % and temperature between 20–25 °C; high humidity interferes with mite reproduction, while extreme heat reduces survival. Increase air circulation with fans to disperse leaf‑bound webs and improve leaf drying.
An integrated pest management program combines these tactics: monitor regularly, maintain sanitation, employ resistant cultivars, release predatory mites, use selective miticides when thresholds are exceeded, and optimize greenhouse climate. This coordinated approach minimizes chemical inputs, preserves natural enemies, and sustains cucumber productivity.