Zone Forge reads your Washington soil test in Washington's own calibrated language — the critical levels and rate logic come straight from WSU Extension — East/West Cascade nutrient + Inland NW lime (combined source), not a national average.
Published source: WSU Extension — East/West Cascade nutrient + Inland NW lime (combined source)
WSU Extension — East/West Cascade nutrient + Inland NW lime (combined source). Zone Forge cites the publication on every recommendation.
Yes — the Washington 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 Washington soil test in its own state's language, then builds source-cited fertilizer and lime recommendations and full variable-rate prescriptions. See the science →