OSU Organic Fertilizer & Cover Crop Calculator

This free online tool compares the nutrient value and cost of cover crops, organic and synthetic fertilizers and compost. Use this Excel Calculator to develop well balanced and cost effective nutrient management programs for your farm. Developed by Nick Andrews, Dan Sullivan, Jim Julian and Kristin Pool.

Quick Guide & Records Sheet The Quick Guide describes the main steps used to sample cover crops in the field, list the laboratory analyses required and describe how to use the Calculator.

Cover Crop Sampling Instructions These instructions describe the recommended method for sampling and analysing cover crops in more detail than the Quick Guide.

Organic Fertilizer & Cover Crop Calculator (per acre calculations for cover crops and fertilizers).

Small Farm/Garden Calculator (square foot calculations for fertilizers only).

Research Background This page links to research papers and other information that explains how the calculator was developed.