Damping off in microgreens is caused primarily by fungal pathogens such as Pythium, Rhizoctonia, and Fusarium. These fungi thrive in moist, warm environments and attack the seeds or seedlings, leading to poor germination, seedling collapse, and death. Several factors contribute to damping off, including:
- Overwatering: Excess moisture creates the perfect environment for fungi to grow. Solution: Make sure to dry out the growmedia between each watering cycle.
- Poor air circulation: High humidity and lack of airflow promote fungal growth.Solution: Add more fans, small 12v computer fans works great to move a lot of air, for long periods of time.
- Contaminated soil or trays: Using unsterilized or non-sterile growing media can introduce harmful pathogens. solution: Use an non-soil media to reduce this.
- Crowded conditions: Dense planting can reduce airflow and trap moisture, increasing the risk of infection. Solution: make sure to spread out your seeds more and make sure they don't clump up.
- Temperature fluctuations: Warm, humid conditions favor fungal development, especially in indoor or greenhouse settings. solution: keep between 21-23 C and about 40-60 % humidity.
Preventive measures include using sterile soil, ensuring proper drainage, avoiding overwatering, and promoting air circulation by using fans or spacing out seedlings