How do I store unused nematodes?
Written by
Michael Sullivan
Reviewed by
Prof. Charles Hartman, Ph.D.Proper storage greatly extends beneficial nematode viability. These living organisms require conditions to be functional, and I found this out the hard way after losing valuable nematodes due to incorrect refrigeration methods. If maintained at 38-46 °F (3-8 °C), they remain dormant but alive until application.
Temperature Control
- Maintain consistent 38-46°F (3-8°C) in refrigerator
- Use a dedicated thermometer to monitor fluctuations
- Avoid refrigerator doors where temperatures vary
Light Protection
- Keep packages in opaque containers or wrapped in foil
- Never store near windows or under bright lights
- UV radiation destroys nematodes within minutes
Moisture Management
- Ensure packaging remains completely sealed
- Add damp paper towel if storing opened packages
- Prevent condensation buildup during temperature changes
The timing of refrigeration plays a large role in efficacy. Nematodes consistently lose 10% of their viability each week, even under ideal refrigerated conditions. Therefore, it is critical to pay attention to purchase dates and apply within four weeks. I assign expiration dates to standard nematode containers with waterproof markers. Stock is rotated using a first-in, first-out system.
Proper handling of thawed nematodes is essential. Once packages are at room temperature, they should be used right away. Do not refrigerate after warming. I transport nematodes in a small cooler with ice packs to gardens. This preserves the cold chain between the refrigerator and the point of application.
Identify signs of expiration. Healthy nematodes will appear as a light brown powder. Discard if you notice sour smells or if clumping occurs. For my viability test, I mix some of the samples with water. Active nematodes will exhibit signs of wriggling movement when viewed under magnification. I look for movement but expect to see it in 30 minutes or less.
Read the full article: Beneficial Nematodes Garden Pest Control
