White Fungus on Philodendron: Powdery Mildew Treatment

Diagnosis: Powdery Mildew

White, wipe-off-able coating that returns = powdery mildew. Triggered by cool, damp, stagnant air (A/C mornings + overwatering).

Treatment

1. Drain excess water. Keep soil on the dry side—let dry completely between waterings.
2. Spray Lysol (or generic) twice daily for 1 week, then daily for week 2, then 1–2×/week for maintenance. Cover all leaf surfaces.
3. Increase air circulation. Fan on low, spaced from other plants.
4. Remove severely affected leaves.

Prevention

• Water at soil level, not foliage.
• Philodendrons like to dry out several days between waterings.
• Avoid cold, damp drafts.