Organic Fertilizer and Cover Crop Calculators

Select a calculator for your region:

  • West of the Cascades - Excel calculator for estimating costs, cover crop and fertilizer PAN and other fertilizer nutrients, with options for 1000sf or per acre calculations. Developed by OSU for western Oregon and Washington Mediterranean climate (Nick Andrews, Dan Sullivan, Jim Julian and Kristin Pool).

  • East of the Cascades - online cover crop PAN calculator. Developed by University of Idaho for irrigated fields in their arid climate (Amber Moore, Christi Falen, Lauren Hunter, Glenn Shewmaker and David Graybill).

  • Hawaii and their tropical climates - Excel cover crop PAN calculator under development at the University of Hawaii.

Information and resources


This work was sponsored by Western Sustainable Agriculture Research and Education (projects FW06-301 and FW09-328), Oregon Tilth, Inc. and the OSU Oregon Organic Cropping Research program.

We also thank Stutzman Environmental Products, Concentrates Inc., Wilbur-Ellis Company, and Bridgewell Resources for supporting this work with their donations.