How to treat soil in a greenhouse against spider mites before planting cucumbers in polycarbonate? - briefly
Treat the growing medium with a pre‑plant drench of neem oil or a registered miticide, then solarize or steam‑sterilize the beds to eliminate spider‑mite eggs before sowing cucumbers in polycarbonate structures. Maintain low humidity and regularly remove plant debris to prevent reinfestation.
How to treat soil in a greenhouse against spider mites before planting cucumbers in polycarbonate? - in detail
Treat the growing medium before sowing cucumbers under polycarbonate by eliminating spider‑mite populations and preventing future infestations.
Begin with thorough sanitation. Remove all plant debris, empty containers, and old mulch. Disinfect tools and benches with a 10 % bleach solution or a quaternary ammonium compound. Clean the greenhouse interior, paying special attention to cracks and joints where mites can hide.
Apply soil solarization if temperatures allow. Moisten the soil to field capacity, cover it with clear polyethylene film, and seal the edges. Maintain the cover for 4–6 weeks during the hottest period; the combined heat and moisture kill eggs, larvae, and adults residing in the substrate.
Introduce biological antagonists directly into the soil. Beneficial predatory mites such as Phytoseiulus persimilis and Neoseiulus californicus establish quickly and suppress spider‑mite colonies. Apply a starter culture according to the supplier’s rate, distributing it evenly across the planting area.
If a chemical measure is required, select a miticide that is registered for soil application and compatible with cucumbers. Products containing abamectin, spirodiclofen, or chlorpyrifos‑methyl can be mixed with irrigation water and applied as a drench at the label‑specified concentration. Rotate active ingredients to avoid resistance buildup.
After treatment, install a monitoring system. Place sticky cards or white‑paper traps at canopy level and inspect them weekly. Record mite counts and adjust control tactics if thresholds are exceeded.
Finally, maintain optimal cultural conditions. Keep relative humidity between 60–70 % and temperature around 22–26 °C, as excessive dryness encourages mite dispersal. Use drip irrigation to keep the substrate uniformly moist, reducing stress on cucumber seedlings and limiting mite reproduction.
By integrating sanitation, solarization, biological agents, judicious chemical use, and vigilant monitoring, the soil environment becomes inhospitable to spider mites, ensuring a healthy start for cucumber cultivation under polycarbonate cover.