Brown Spots on parlor palm
What's Happening
Brown spots on parlor palm leaves are frequently misdiagnosed as fungal infections when they are actually caused by spider mites or other piercing-sucking pests. Mites feed on leaf cells, causing characteristic stippling—tiny yellow or brown dots that coalesce into larger brown patches. Unlike fungal spots (which often have defined margins and may appear water-soaked), mite damage shows as diffuse bronzing, especially on leaf undersides.
How to Fix It
- 1
Inspect leaf undersides with a magnifying glass for tiny moving specks or fine webbing
- 2
Perform the 'paper towel test'—wipe leaf undersides with a white paper towel; red/orange streaks indicate mites
- 3
Treat with neem oil or insecticidal soap weekly for 3-4 weeks, ensuring coverage of leaf undersides
- 4
Increase humidity immediately—mites cannot reproduce above 60% humidity
- 5
Consider predatory mites (Phytoseiulus persimilis) for severe infestations
- 6
Isolate affected plants to prevent spread
How to Prevent It
Quarantine new plants for 2-3 weeks. Maintain 50-60% humidity. Inspect leaf undersides weekly during dry winter months when mites are most active.