Can I apply nematodes with fertilizer?
Written by
Michael Sullivan
Reviewed by
Prof. Charles Hartman, Ph.D.When combining nematodes with fertilizers, proper timing is essential to avoid losses in effectiveness. Nematodes are quite sensitive to changes in pH and chemical residues. I learned this the hard way when I reduced the nematode effectiveness by 50% by using fish emulsion simultaneously. Timing both treatments correctly ensures that each receives the maximum benefit.
Organic Fertilizers
- Compost tea: Apply simultaneously or immediately after nematodes
- Fish emulsion: Wait 24 hours before or after treatment
- Seaweed extract: Fully compatible with no waiting period
Chemical Fertilizers
- Synthetic NPK formulas: Separate by 5 days minimum
- Urea-based products: Wait 7 days before nematode application
- Slow-release granules: Incorporate 2 weeks prior
Soil Amendments
- Lime: Apply 14 days before nematodes to stabilize pH
- Gypsum: Safe for simultaneous application
- Biochar: Mix into soil 10 days prior
Chemical fertilizers are likely the most damaging due to their effects on salt and pH levels. Increased levels of nitrogen can harm nematodes; pH levels below 6.0 or above 7.5 can reduce their mobility. My soil tests indicate that pH normalization can take 5-7 days to occur after applying synthetic fertilizer.
Utilize this safe integration method. First, water-in fertilizers thoroughly. Wait for the specified days for the product type. Ensure the soil pH remains between 6.0 and 7.5. Apply nematodes at dawn. Lastly, maintain consistent moisture for ten days between applications to support both treatments.
Organic options blend in more smoothly. I use nematodes, combined with compost tea, every week on my vegetables. The microbial boost enhances the effectiveness of the nematodes. As always, begin with a small area to test any new fertilizer combinations. I write down results like this, for future reference. You might want to do the same.
Read the full article: Beneficial Nematodes Garden Pest Control
