Zone Forge reads your Oklahoma soil test in Oklahoma's own calibrated language — the critical levels and rate logic come straight from Oklahoma — OSU SWFAL (PSS-2225) combined lime + nutrient source, not a national average. Lime has its own live calculator for Oklahoma with method-specific lab inputs.
Per Oklahoma — OSU SWFAL (PSS-2225) combined lime + nutrient source — below the critical level, a yield response to the added nutrient is expected.
Oklahoma — OSU SWFAL (PSS-2225) combined lime + nutrient source rates these crops in Oklahoma:
More crops via alternate guides selectable in Oklahoma: Great Plains Canola Production Handbook (MF2734).
Published source: Oklahoma — OSU SWFAL (PSS-2225) combined lime + nutrient source
Oklahoma — OSU SWFAL (PSS-2225) combined lime + nutrient source. Zone Forge cites the publication on every recommendation.
Yes — the Oklahoma soil-test recommendation calculator is free and needs no signup. Enter your lab values for source-cited P and K; Oklahoma's live lime calculator is available separately with its own required lab inputs.
Yes — the free soil-test calculator covers source-cited P and K. Oklahoma also has a live lime calculator on Zone Forge that uses the state's published method. Open the Oklahoma lime guide or lime calculator for tons of CaCO3-equivalent per acre.
Zone Forge reads every Oklahoma 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 →