How should ammonia be diluted for spider mite control? - briefly
Mix household ammonia (5‑10 % concentration) with water at a 1:9 ratio (one part ammonia to nine parts water) and spray the solution onto affected foliage until thoroughly wet. Reapply after 7‑10 days, monitoring plant response for any signs of phytotoxicity.
How should ammonia be diluted for spider mite control? - in detail
Ammonia can be an effective mite‑killing spray when mixed to the correct strength and applied properly. The recommended dilution is 1 part household ammonia (5‑10 % w/v) to 10 parts water, yielding a solution of roughly 0.5‑1 % ammonia. This concentration is strong enough to penetrate the mite’s waxy coating while remaining safe for most foliage.
Preparation steps
- Measure 100 ml of clear ammonia.
- Add the measured ammonia to 1 liter of lukewarm water.
- Stir gently to ensure even distribution; avoid vigorous shaking that can create foam.
- Optional: add a few drops of mild liquid soap (non‑ionic, pH‑neutral) to improve leaf coverage and adherence.
Application guidelines
- Test the mixture on a single leaf for 24 hours; observe for any phytotoxic symptoms such as discoloration or leaf burn.
- Apply the spray early in the morning or late afternoon to reduce evaporation and sun‑induced leaf damage.
- Ensure thorough wetting of the undersides of leaves where spider mites reside; use a fine‑mist nozzle.
- Treat all affected plants, including stems and surrounding soil surface if mites are present in the substrate.
Safety precautions
- Wear gloves, goggles, and a mask to avoid inhalation and skin contact.
- Keep the solution away from edible parts of crops; do not use on leafy greens intended for raw consumption.
- Store any unused mixture in a clearly labeled, sealed container; discard after 24 hours to prevent degradation.
Re‑treatment schedule
- Repeat the application every 5‑7 days until mite populations are no longer observed.
- After three consecutive applications, assess the need for continued treatment; excessive use can lead to plant stress.
Compatibility considerations
- Do not combine with strong acids, bleach, or other high‑pH chemicals; they can neutralize the ammonia’s effect.
- Avoid mixing with copper‑based fungicides, which may cause leaf injury.
Following these precise mixing ratios, application practices, and safety measures maximizes mite control while minimizing risk to plant health.