Optimizing nitrogen management on organic and biologically-intensive farms

Project Overview

Project Type: Professional + Producer
Funds awarded in 2015: $49,997.00
Projected End Date: 12/31/2017
Region: Western
State: Washington
Principal Investigator:

Annual Reports

Information Products


  • Vegetables: broccoli


  • Crop Production: organic fertilizers
  • Production Systems: organic agriculture


    The long-term goal of this project is to improve nitrogen fertilizer management on farms implementing biologically-intensive soil-building practices to grow diverse crops. Cover cropping and organic amendments contribute to the soil’s fertility beyond the year they were incorporated by building active organic matter. Through this participatory research we will be able to place dollar values on the importance of optimizing soil fertility. Growers will be able to more accurately estimate nitrogen mineralization from soil organic matter and adjust fertilizer applications up or down accordingly. Extensive outreach efforts will be used to directly reach over 200 growers in Washington and Oregon.

    Project objectives:

    1. Assist producers with fertilizer applications through pre-season soil tests that predict nitrogen mineralization.
    2. Evaluate the net economic return of increasing amounts of organic fertilizer applied before planting across geographically dispersed farms with differing soil quality parameters.
    3. Assist producers with in-season soil tests that allow adjustment to fertility during the growing season.
    4. Assist producers in developing nitrogen management plans to increase profitability while protecting water quality.
    Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.