Corn Plant Decline: Overwatering and Fluoride Toxicity

A 6-month-old corn plant (Dracaena fragrans 'Massangeana') on south wall (indirect light) watered biweekly with tap water developed yellow/brown leaves spreading from sides, not just tips. Owner confused between over/underwatering.

Diagnosis: Overwatering + Fluoride Damage

• Overwatering: Watering before bone-dry prevents root CO₂ exchange → root rot → yellow leaves.
• Fluoride/Chlorine: Dracaenas hate both → brown spots → yellowing → death.

Corrective Steps

1. Stop tap water. Use distilled or let sit 48 hours open.
2. Water only when pot feels light (tilt test).
3. Dry 2–3 days between waterings for root respiration.
4. Expect 2–3 weeks before next watering.

Moisture Testing

Buy $15 soil probe meter (Menards, Lowe's, Home Depot) or master the tilt test.

Underwatering this plant is very difficult—err dry.