No-till and Strip-till Systems for Enhanced Soil Health and Profitability in Organic Broccoli and Pepper Production

Project Overview

Project Type: Graduate Student
Funds awarded in 2014: $9,946.00
Projected End Date: 12/31/2015
Grant Recipient: Iowa State University
Region: North Central
State: Iowa
Graduate Student:
Faculty Advisor:
Dr. Ajay Nair
Department of Horticulture, Iowa State University

Information Products


  • Vegetables: broccoli, peppers


  • Crop Production: conservation tillage
  • Farm Business Management: agricultural finance, budgets/cost and returns
  • Production Systems: organic agriculture, transitioning to organic
  • Soil Management: green manures, nutrient mineralization, organic matter, soil analysis, soil quality/health

    Proposal abstract:

    Organic no-till and strip-till systems have gained attention because of their capacity to enhance soil health and suppress annual weeds. The proposed research, entitled, “No-till and Strip-till Systems for Enhanced Soil Health and Profitability in Organic Broccoli and Pepper Production,” will compare no tillage, strip tillage, and conventional tillage in organic production of broccoli and bell pepper, and determine their effects on yield, soil health, and cropping system profitability. All treatments will include a cereal rye/hairy vetch cover crop, which will be seeded in the fall and either roller-crimped (no-till and strip-till) or tilled-in (conventional-till) in late spring of the following year. Each tillage treatment plot will be split into two fertility regimes—one based entirely on pre-plant granular fertilizer, and the other split between the granular fertilizer and post-planting fertigation—to test the effect of fertigation on yields under the typically N-limited reduced tillage conditions.  Data will be collected on crop growth, yield, and quality; cover crop biomass; soil moisture and temperature; in situ N mineralization; plant tissue NO3- and NH4+, microbial biomass; and nitrate leaching. Our hypothesis is that reduced tillage, paired with split N application using supplemental fertigation, will improve soil health while maintaining crop yields. Results will be disseminated via field days at the research station and a collaborating farm, poster presentations at annual growers conferences, written extension bulletins, and a peer-reviewed journal publication. Short-term outcomes include a better understanding of the factors affecting productivity in reduced tillage organic vegetable systems and increased grower knowledge of the principles and practices of no tillage and strip tillage. Project impacts will be measured using follow-up surveys of field day attendees and by holding focus groups at growers conferences.

    Project objectives from proposal:

    The soils on many farms in the North Central region are susceptible to soil and nutrient loss through erosion and leaching. Changing from conventional to reduced tillage can minimize many adverse effects of tillage, but requires a fundamental paradigm shift on the part of growers. For that reason, this project has many learning outcomes aimed at increasing grower understanding of the principles and practices of reduced tillage systems. As a result of this research and its associated outputs (publications, field days, videos, etc.), farmers will: understand the principles underlying cover crop-based no-till and strip-till (hereafter also referred to collectively as reduced tillage) systems; appreciate short- and long-term impacts of reduced tillage and cover crops on soil and water quality; understand potentially yield-limiting factors and be aware of practices that mitigate their effects; be able to identify the appropriate growth stages of cereal rye and hairy vetch for mechanical termination;  and be aware of the equipment needed for no-till and strip-till, including where to buy it and how to adjust it properly for their conditions.


    While learning is the necessary precursor to adoption, the ultimate goal of this study is to stimulate management changes on farms in the North Central region. Using the new knowledge and skills obtained through this study’s outreach, farmers will plant more cover crops, use tillage more sparingly, and eventually incorporate no tillage and/or strip tillage into their operations. 

    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.