Improvements made to Fertilizer and Cover Crop Calculator

July 6, 2020

Evaluating cover crop options, an essential part of healthy and resilient farms, is tricky. ⁠ ⁠

In partnership with Oregon State University, we launched the Organic Fertilizer and Cover Crop Calculator in 2005. This free online tool helps farmers compare the nutrient values and costs of cover crops, fertilizers, and compost. Users enter fertilizer and labor costs to compare against a nutrient management plan using cover crops.

Our friends at the OSU Small Farms Program recently improved how the calculator forecasts nitrogen availability.⁠ ⁠The changes allow farmers to predict available nitrogen at four weeks and ten weeks. Users can review eight cover crops at a time (up from three). The calculator enables farmers to estimate the fertilizer value of a cover crop and the best time to plant.

The tool comes with a quick guide and records sheet to help users get started. And for those who want to nerd out, you can review detailed publications on cover crop sampling methods and the research behind it all.

Please help us share this tool with more farmers. The Western Cover Crop Council will launch a website for the new-and-improved calculator soon. We’re excited to serve on the Council’s board and appreciate OSU’s continued partnership and support.

View Organic Fertilizer and Cover Crop Calculator

Contact Information

Oregon Tilth Main Office
PO Box 368
Corvallis, OR 97339
Phone: (503) 378-0690
Toll Free: (877) 378-0690

Recent News

Join Us / Careers


We’re looking for people who share our ambition, innovation and enthusiasm. Our team consists of people with an endless passion for the all of the small things that make up our mission. Join us.

Learn More