Comparing Organic No till with Conventional Tillage methods when Direct Seeding Vegetables and Incorporating Cover Crops

Project Overview

Project Type: Farmer/Rancher
Funds awarded in 2012: $14,701.00
Projected End Date: 12/31/2013
Region: Western
State: Washington
Principal Investigator:

Information Products


  • Vegetables: carrots, greens (leafy)


  • Crop Production: conservation tillage
  • Education and Training: demonstration, extension, on-farm/ranch research, participatory research, workshop
  • Natural Resources/Environment: biodiversity
  • Pest Management: biological control
  • Production Systems: holistic management, organic agriculture, permaculture
  • Soil Management: earthworms, green manures, organic matter, soil analysis
  • Sustainable Communities: public participation

    Proposal summary:

    Current Operation

    We, Gary Miller & Amy Plant, are currently producing a wide range of organic vegetables for year round, local markets on one acre with assistance from interns. Education and experimentation is important to our operation.

    Our main cash crops are salad greens and carrots, directly seeded into raised beds. Other vegetables, such as tomatoes, are started in a greenhouse for transplanting. For the past two years, we have been converting to no-till. Fertility is maintained by cover crops, local manure and minimal amendments. Our aim is to combine organic and no-till methods that are economically and environmentally sustainable. For this experiment we will use conventional tillage methods in designated test plots.

    Context & Problems

    The poor glacial remnant soils of our region are a challenge to successful farming. Our soils are shallow, wet and high in clay content. How can we improve soils in these conditions?  No-till lends itself to this challenge by reducing the risk of soil compaction and increasing organic matter, as well as permitting earlier planting dates.

    Most organic farming still depends on tillage despite its major problems of soil erosion and soil structure damage. "Tillage reduces earthworm populations, fungal based food webs, organic matter, soil aggregates, and initiates germination of many weed species." (Tilth Producers Quarterly, Spring ‘11). This 'organic contradiction' is pointed out by Tim Steury in Washington State University Magazine, Fall ’11: "Combining no-till and organic right now might be one of the holy grails of production agriculture." Research on organic no-till systems has included corn and wheat, but little has been done with vegetables that are directly seeded.


    We believe organic no-till improves soil organic matter, prevents soil erosion, reduces water run off and the leaching of nutrients into ground and surface water. It increases earthworm populations, maintains microbes, springtails and nematodes. It reduces reliance on fossil fuels that contribute to greenhouse gases and the need for non-renewable amendments. On-farm resources of water, equipment and labor are reduced. No-till works with nature, mimicking an eco-system where the microorganism community is able to provide fertility and maintain or increase plant productivity.

    No-till potentially reduces labor, increases profitability and allows for earlier planting.

    Benefits and impacts to agriculture

    No-till has potential to:

    - Improve soil quality, increasing yields: research by Doug Collins shows major increase in organic matter.
    - Lower production costs of labor, inputs, fuel and equipment. E.g. tractor costs = $3,000 per year over 20 years.
    - Cut water use by 30%.
    - Reduce soil erosion. Savings due to wind erosion can be five tons in no-till. In wet soils there is negligible loss of nitrogen or phosphate compared to conventional till. (‘MSU Extension Nutrient Management in No Till and Minimum Till Systems’, 2008).
    - Improve markets.

    Project objectives from proposal:

    1. Use no-till to build prime agricultural soil in a region that has no class 1 soils.
    2. Develop innovative methods for direct seeded salad greens using a no-till system.
    3. Effectively integrate cover crops/manure using a no-till system.
    4. Develop planting/cover cropping schedules that allow earlier planting dates.
    5. Compare soil quality and weed pressure between tilled and no-tilled plots.
    6. Measure economic benefits.
    7. Measure potential benefits to agriculture and soil improvement.  
    8. Encourage adoption of methods/educate wider public.

    A two-year experiment will compare the following four treatments using a fava bean cover crop, manure amendments and a mixed salad green cash crop.

            1) No-till + manure amendment
            2) Tillage* + manure amendment
            3) No-till + cover crop and manure amendment
            4) Tillage* + cover crop and manure amendment

    * Tillage and cover crop incorporation will be performed using standard rotor till.

    Two practical workshop/field days with guest speakers: Larry Korn, Doug Collins (WSU) and Andy Bary (WSU)

    Educational or Informational Materials Provided

    1) Website with blog updates
    2) Facebook page
    3) No-till TV: a series of bi-monthly, demonstration videos on You Tube.
    4) DVDs of complete video series
    5) Practical, illustrated fact sheets with step-by-step guides and project findings
    6) Copies of articles providing information on the wider issues

    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.