Is Locally Sourced Biochar and Poultry Litter the Solution to Improving Soil Health and Sustainably Produce Tomatoes in South Georgia?

Project Overview

Project Type: Graduate Student
Funds awarded in 2023: $16,500.00
Projected End Date: 08/31/2025
Grant Recipient: University of Georgia
Region: Southern
State: Georgia
Graduate Student:
Major Professor:
Ted McAvoy
University of Georgia


  • Vegetables: tomatoes


  • Animal Production: manure management
  • Crop Production: fertilizers
  • Soil Management: soil quality/health

    Proposal abstract:

    This project aims to assess the effectiveness of biochar, a type of charcoal produced through pyrolysis, on soil health and crop productivity in South Georgia. The study will use biochar at different rates (0, 5, 10, 15, and 20 tons/acre) in combination with organic (poultry litter) or inorganic (conventional) fertilizers. The objective is to quantify the effect of these treatments on soil health and yield using standardized monitoring protocols. The study will also analyze the impact on plant growth and development, including the root system, plant mass, tomato fruit yield and quality, as well as the microbial activity of the soil.

    By combining biochar with poultry litter, it is hypothesized that biochar will enhance nutrient retention, thereby reducing nutrient runoff. Additionally, the presence of biochar may also reduce the negative environmental impacts associated with poultry litter alone. The project will evaluate the response of the biochar to soil chemical, physical, and biological properties, including soil health pH, organic matter content, microbial activity, nutrient uptake, and potential for toxic metal accumulation.

    The project utilizes locally sourced byproducts, biochar from the paper mill industry, and poultry litter from Georgia's broiler production, the largest commodity industry in South Georgia. The findings from this research will be shared with farmers to enhance best practices, improve crop management, and address environmental challenges. The results are expected to contribute to the sustainability of southern agriculture by improving profitability, sustaining ecological quality and enhancing the quality of life for farmers, ranchers, and rural communities.
















    Project objectives from proposal:

    Objective 1

    Quantify the effect of biochar at different rates in combination with organic (poultry litter) and inorganic (conventional) fertilizers on soil health and fertility by measuring physical, chemical, and biological soil parameters and nitrogen mineralization in the tomato crop.


    • Established the researched plots for tomatoes and applied different biochar rates (0, 5, 10,15, 20 tons/acre) combined with poultry litter or conventional fertilizer, targeting a nitrogen rate of 220 lbs./acre.
    • Collect soil samples at the season’s beginning, middle, and end to analyze physical, chemical, and biological properties such as rooting depth, aggregate stability, pH, EC, organic matter content, and microbial activity.
    • Collect weekly soil samples of the different treatments to track the nitrogen mineralization.
    • Data collection and analysis

    Outcome Expected

    • Determine the impact on soil health and fertility of biochar at different rates.
    • Quantify the effect of nitrogen mineralization in the different treatments
    • Provide recommendations and rates for optimal crop growth and health.

    Objective 2

    Evaluate the effects of the different treatments on crop yield, vegetable quality, plant compounds, plant growth, and foliar development.


    • Monitor plant growth and development (n=10) by monthly measurements of the stem diameter and height.
    • At the end of the season, harvest the entire tomato plant (n=10) for each treatment to collect fresh mass, then put samples to dry for dry mass.
    • Harvest tomatoes at maturity and measure yield, colors, size, firmness, acidity, lycopene, and carotene content.
    • Collect foliar samples to analyze the content of macro and micronutrients on tissue.

    Outcome Expected

    • Identification of the most effective treatment for increasing crop yield, quality, and nutrient content
    • Improved understanding of the impact of biochar and fertilizer combinations on plant growth and development

    Objective 3

    Disseminate the results to farmers and other stakeholders through workshops, field days, and online platforms, and evaluate their feedback and adoption of the best practices.


    • Develop educational materials, such as brochures, pamphlets, and infographics, to present the research findings and best practices in a clear and accessible format
    • Conduct workshops and field days to provide hands-on training and demonstrations on the use of biochar and fertilizers in crop production
    • Utilize online platforms, such as social media, webinars, and blogs, to reach a wider audience and disseminate information on the research results and best practices

    Outcome Expected

    • Disseminate the research findings to farmers and other stakeholders through various channels
    • Encourage the adoption of best practices for improving soil health and crop yield
    • Increase awareness and knowledge among farmers and stakeholders about the benefits of biochar and its optimal use in combination with organic or inorganic fertilizers.


    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.