Prevent Damping Off: Keep Seedlings Healthy from the Start

Damping off—seed/seedling rot from soil-borne fungi (Pythium, Phytophthora, Rhizoctonia, Fusarium)—strikes in two phases: pre-emergence (seeds rot) and post-emergence (seedlings collapse at soil line).

Prevention Checklist

• Sanitize: Dip flats, tools, pots, benches in 1:4 bleach:water (10 sec) or 70% alcohol
• Soil: Light, well-drained, fertile. Prefer sterile, heat-pasteurized mix
• pH: Maintain low-end average (6.4). Test often; lower with 1 tbsp vinegar/gal water if rising
• Depth: Sow seeds ≤4x their thickness
• Moisture: Keep seedbed dry side after sowing. Bright indirect light. Water from bottom only. No standing water. Never water late day.
• Spacing: Avoid overcrowding
• Feeding: No overfertilizing, especially nitrogen

Why It Works

Fungi thrive in cold, wet, unhygienic conditions. Clean, airy, slightly acidic, well-drained starts deny them a foothold.

Start clean, stay vigilant—your seedlings will thrive.