How to get rid of a shell mite on an orchid? - briefly
Apply a horticultural oil or neem‑based miticide to the orchid, covering all foliage and roots, and isolate the plant to avoid cross‑contamination. Repeat the treatment every 7‑10 days until mites are no longer visible, then maintain lower humidity and regular inspections to prevent recurrence.
How to get rid of a shell mite on an orchid? - in detail
Shell mites (Cheyletus eruditus) infest orchid foliage by feeding on cell sap, causing stippling, discoloration, and leaf drop. Early detection relies on close inspection of leaf surfaces, especially the undersides, where tiny moving specks are visible under magnification.
Identification steps
- Examine leaves with a hand lens; mites appear as translucent, elongated bodies, 0.2–0.4 mm long.
- Look for fine yellow or brown stippling that expands into larger necrotic patches.
- Confirm presence by gently shaking the plant over white paper; falling mites become apparent.
Cultural controls
- Reduce humidity to 40–50 % for a week; mites thrive in overly moist environments.
- Increase airflow around the orchid, avoiding stagnant air pockets.
- Remove dead or heavily damaged leaves; dispose of them away from healthy plants.
Chemical and biological measures
- Apply neem oil at 2 % concentration, spraying both upper and lower leaf surfaces until runoff. Repeat every seven days for three applications.
- Use horticultural oil (e.g., mineral oil) at 1 % dilution, covering foliage thoroughly; repeat after ten days.
- Introduce predatory mites (Neoseiulus californicus) according to manufacturer dosage; maintain temperature above 18 °C for optimal predator activity.
Sanitation practices
- Sterilize pots, trays, and tools with a 10 % bleach solution before reuse.
- Quarantine newly acquired orchids for at least four weeks, monitoring for mite activity.
- Avoid reusing orchid bark without heat treatment (minimum 60 °C for 30 minutes).
Monitoring protocol
- Inspect plants weekly for two months after treatment.
- Record mite counts on a simple tally sheet to assess population trends.
- Continue preventive sprays (neem or horticultural oil) at monthly intervals during the growing season.
By combining early detection, environmental adjustments, targeted sprays, biological agents, and strict sanitation, infestations can be eliminated and orchid health restored.