How to fight a spider mite on cucumbers? - briefly
Apply horticultural oil or insecticidal soap early in the morning, and introduce predatory mites (e.g., Phytoseiulus persimilis) to suppress populations; maintain low humidity, adequate airflow, and remove heavily infested foliage. Rotate crops and avoid excessive nitrogen fertilization to prevent future outbreaks.
How to fight a spider mite on cucumbers? - in detail
Spider mites (Tetranychidae) attack cucumber foliage by piercing cells and extracting sap, leading to stippling, yellowing, and leaf drop. Early detection relies on visual inspection of the undersides of leaves for tiny moving dots or fine webbing.
Control measures combine cultural, biological, and chemical tactics.
- Sanitation: Remove heavily infested leaves, discard plant debris, and clean tools after each use.
- Water spray: Apply a strong jet of water to foliage twice weekly; the force dislodges mites and reduces population density.
- Host‑plant resistance: Choose cucumber varieties reported to exhibit lower susceptibility, such as those with thicker leaf cuticles.
- Predatory insects: Release Phytoseiulus persimilis or Neoseiulus californicus at a rate of 10–15 adults per square meter; these predatory mites consume up to five spider mites per day.
- Botanical oils: Apply neem oil or horticultural oil at 1–2 % concentration, covering both leaf surfaces. Repeat every 7–10 days, avoiding application during extreme heat to prevent phytotoxicity.
- Insecticidal soaps: Use potassium salts of fatty acids at label‑recommended dosage; ensure thorough coverage of leaf undersides. Reapply after rain or irrigation.
- Synthetic acaricides: When mite numbers exceed economic thresholds, rotate products with different modes of action (e.g., abamectin, spiromesifen, bifenazate). Observe pre‑harvest intervals and resistance‑management guidelines.
Monitoring continues throughout the growing season. Sticky traps placed at canopy height capture mobile stages and provide a quantitative estimate of infestation pressure. Adjust treatment frequency based on trap counts and leaf damage assessments.
Integrating these strategies reduces mite pressure, preserves cucumber yield, and minimizes reliance on chemical controls.