North Dakota · Soil test

North Dakota soil-test fertilizer recommendations

Zone Forge reads your North Dakota soil test in North Dakota's own calibrated language — the critical levels and rate logic come straight from NDSU SF-882 — North Dakota Fertilizer Recommendation Tables and Equations + simple-rule lime, not a national average.

Critical soil-test levels

  • P: critical 8 ppm (Olsen P)
  • K: critical 81 ppm (ammonium acetate)

Per NDSU SF-882 — North Dakota Fertilizer Recommendation Tables and Equations + simple-rule lime — below the critical level, a yield response to the added nutrient is expected.

Published source: NDSU SF-882 — North Dakota Fertilizer Recommendation Tables and Equations + simple-rule lime

Frequently asked

What soil-test method does North Dakota use?

NDSU SF-882 — North Dakota Fertilizer Recommendation Tables and Equations + simple-rule lime. Zone Forge cites the publication on every recommendation.

Is the North Dakota soil-test calculator free?

Yes — the North Dakota soil-test recommendation calculator is free and needs no signup. Enter your lab values for source-cited P, K and lime guidance.

Zone Forge reads every North Dakota soil test in its own state's language, then builds source-cited fertilizer and lime recommendations and full variable-rate prescriptions. See the science →