What should I spray on cucumbers to control spider mite during fruiting in a greenhouse using folk remedies? - briefly
Use a spray of 1‑2 % neem oil or a solution of water, a few drops of mild liquid soap and a teaspoon of powdered garlic, applied every 5–7 days, to suppress spider mites on fruiting cucumbers in a greenhouse. Both formulations are safe for edible produce when the fruit is rinsed before harvest.
What should I spray on cucumbers to control spider mite during fruiting in a greenhouse using folk remedies? - in detail
Spider mites thrive on cucumber plants when humidity drops below 50 % and temperatures stay above 24 °C. During the fruit‑setting stage the insects can damage leaves and reduce yield, so timely intervention with readily available botanical sprays is essential.
Effective folk preparations
- Neem‑oil emulsion – Mix 2 ml cold‑pressed neem oil with 1 ml liquid soap in 1 l water. Apply until runoff, early morning or late afternoon, every 5–7 days. Neem disrupts mite feeding and reproduction.
- Garlic‑pepper spray – Blend 4 cloves of garlic, 1 tsp crushed hot chili, 1 tsp liquid soap, and 1 l water. Let steep 24 h, strain, and spray to fully covered foliage. Capsaicin and sulfur compounds act as repellents.
- Rosemary tea – Boil 30 g dried rosemary in 1 l water, cool, add 1 tsp soap, and spray. Repeat weekly. The essential oils have acaricidal properties.
- Tobacco‑water extract – Soak 50 g fresh tobacco leaves in 1 l water for 12 h, filter, add 1 tsp soap, and spray. Use with caution; limit to early fruit development to avoid residue on mature cucumbers.
- Insecticidal soap – Dissolve 5 ml pure liquid soap in 1 l water. Spray directly on mites; the surfactant penetrates the cuticle, causing desiccation. Apply every 3 days until populations drop.
Application guidelines
- Test each solution on a few leaves 24 h before full coverage to detect phytotoxic reactions.
- Spray both upper and lower leaf surfaces; mites often hide on the underside.
- Ensure thorough coverage during the fruiting period, but avoid heavy rain forecast within 24 h to prevent runoff.
- Rotate between two different sprays (e.g., neem oil and garlic‑pepper) to reduce the risk of mite resistance.
Cultural measures that reinforce sprays
- Raise greenhouse humidity to 60–70 % using misting or humidifiers; higher moisture suppresses mite reproduction.
- Provide steady airflow with fans to prevent stagnant air pockets.
- Remove plant debris and old leaves where mites can overwinter.
- Use reflective mulch to deter mites from landing on foliage.
Safety considerations
- Wear gloves and eye protection when handling concentrated extracts.
- Do not apply sprays when fruit is at marketable size; wash cucumbers thoroughly before consumption.
- Store homemade solutions in sealed containers, label with preparation date, and discard after two weeks.
Combining these botanical sprays with proper greenhouse management delivers reliable control of spider mites on cucumbers during the critical fruiting phase without resorting to synthetic chemicals.