Russ; I' d get a sample of good soil, even purchased top soil to see what the meter reads for fertility. The rain should help move the fertilizer into the soil. Phosphate moves very slow (as slow as an inch down per year).

I send out soil samples in an approx. 3x2x5" boxes for complete analysis. You should take several samples from a field and mix them together when you make up your sample. You end up with excess soil to test with your meter.

Earthworms are a good sign of organic matter in the soil. They need crop residues to feed on.

Try a few more tests on soils in different areas, especially in a fertilized, well growing farm field. It' ll be interesting to see if the meter varies from good soil to poor.

Dan O.