Zone Forge reads your Wisconsin soil test in Wisconsin's own calibrated language — the critical levels and rate logic come straight from UW Madison Extension A2809 — Nutrient Application Guidelines for Field, Vegetable, and Fruit Crops in Wisconsin, not a national average.
Per UW Madison Extension A2809 — Nutrient Application Guidelines for Field, Vegetable, and Fruit Crops in Wisconsin — below the critical level, a yield response to the added nutrient is expected.
Published source: UW Madison Extension A2809 — Nutrient Application Guidelines for Field, Vegetable, and Fruit Crops in Wisconsin
UW Madison Extension A2809 — Nutrient Application Guidelines for Field, Vegetable, and Fruit Crops in Wisconsin. Zone Forge cites the publication on every recommendation.
Yes — the Wisconsin 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 Wisconsin soil test in its own state's language, then builds source-cited fertilizer and lime recommendations and full variable-rate prescriptions. See the science →