Nutrient management on organic vegetable farms: A research and education program for sustainable soil fertility management in southern New England

Project Overview

Project Type: Research and Education
Funds awarded in 2009: $148,375.00
Projected End Date: 12/31/2013
Region: Northeast
State: Massachusetts
Project Leader:
Dr. Beth Hooker
Hampshire College
Beth Hooker
Mount Holyoke College

Annual Reports


  • Vegetables: beans, beets, cabbages, carrots, cauliflower, cucurbits, eggplant, greens (leafy), parsnips, peas (culinary), peppers, radishes (culinary), sweet corn, tomatoes, turnips, brussel sprouts
  • Additional Plants: herbs


  • Animal Production: manure management
  • Crop Production: conservation tillage
  • Education and Training: demonstration, extension, farmer to farmer, mentoring, on-farm/ranch research, participatory research, workshop
  • Natural Resources/Environment: soil stabilization
  • Pest Management: biological control, cultural control, field monitoring/scouting, integrated pest management, mulches - living, mulching - plastic
  • Production Systems: organic agriculture
  • Soil Management: green manures, organic matter, soil analysis, nutrient mineralization, soil microbiology, soil chemistry, soil quality/health

    Proposal abstract:

    Most organic vegetable growers use manures and composts to address their soil fertility needs. However, understanding the nutrient content of biologically-based nutrient inputs and predicting the amount of available nitrogen (N) and phosphorus (P) after repeated organic additions is a perennial problem, especially due to the lack of specific soil testing procedures created for these conditions. Also, while many farmers believe that the slow-release nature of composts minimizes the problem of nutrient leaching or runoff, small amounts of compost have been shown to cause excessive amounts of available soil P and soil nitrate. Recent SARE-funded research conducted by Dr. Tom Morris suggests that organic vegetable growers have difficulties maintaining optimum nutrient levels, with nearly 50% of fields exhibiting above-optimum levels of N and P. As a result of this and other studies, there is an established need for better nutrient management practices for organic farmers. The objectives of this project are two-fold: 1) We intend to create a regional, routine soil test procedure for managing soil fertility on farms that use organic soil amendments, through research conducted on regional organic farms, and in concert with complementary research proposed by Dr. Ellen Mallory at the University of Maine; 2) We will work with organic vegetable growers in Connecticut, Massachusetts, and New Hampshire to address their specific nutrient management challenges and create educational opportunities designed for organic farmers to assess their soil fertility throughout New England.

    Performance targets from proposal:

    From the 225 organic vegetable farmers who participate in the project, 50 farmers will use individual field records, nutrient management tools, soil testing procedures, and, where applicable, stalk tests to reduce N applications by 30 pounds per acre and P2O5 applications by 30 pounds per acre to achieve optimal levels on 540 acres. These practices will lead to more efficient use of soil amendments linked to crop needs and existing soil fertility, which in turn will reduce the amount of nitrate in groundwater, reduce phosphorus loading to freshwater systems, and decrease the cost of production by $12 per acre for N and $12 per acre for P2O5.

    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.