Illinois · Soil test

Illinois soil-test fertilizer recommendations

Zone Forge reads your Illinois soil test in Illinois's own calibrated language — the critical levels and rate logic come straight from Illinois Agronomy Handbook — Chapter 8 (Managing Soil pH and Crop Nutrients), not a national average. Lime has its own live calculator for Illinois with method-specific lab inputs.

Crops covered

Illinois Agronomy Handbook — Chapter 8 (Managing Soil pH and Crop Nutrients) rates these crops in Illinois:

AlfalfaCloverCornCorn silageGrass hayOatsSorghumSoybeansWheat

Published source: Illinois Agronomy Handbook — Chapter 8 (Managing Soil pH and Crop Nutrients)

Frequently asked

What soil-test method does Illinois use?

Illinois Agronomy Handbook — Chapter 8 (Managing Soil pH and Crop Nutrients). Zone Forge cites the publication on every recommendation.

Is the Illinois soil-test calculator free?

Yes — the Illinois soil-test recommendation calculator is free and needs no signup. Enter your lab values for source-cited P and K; Illinois's live lime calculator is available separately with its own required lab inputs.

Can Zone Forge calculate a Illinois lime rate?

Yes — the free soil-test calculator covers source-cited P and K. Illinois also has a live lime calculator on Zone Forge that uses the state's published method. Open the Illinois lime guide or lime calculator for tons of CaCO3-equivalent per acre.

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