Despite its challenges, non-chemical, reduced tillage vegetable production is of continued interest among researchers and growers as a way to improve soil health. Primarily success in this production method has been use of high biomass cover crops such as cereal rye terminated with a roller crimper. However alternative cover crops should be explored to diversify reduced tillage systems and to improve nitrogen synchrony. Sunn hemp (Crotelaria juncea) is a high biomass producing legume with potential to achieve weed suppression while reducing nitrogen immobilization in non-chemical, no-till vegetable production. A two-year study was conducted at the Meigs Horticulture Facility (Meigs) in Lafayette IN to assess the potential of sunn hemp as a cover crop suitable for rolling in a non-chemical, no-till vegetable production system. At Meigs roll success of three sunn hemp rolling dates was evaluated. Followed by Swiss chard production. Sunn hemp was rolled with and I and J roller crimper 60, 70, and 80 days after seeding. Prior to rolling sunn hemp height, above ground biomass (sunn hemp and weed), and roll success was measured 4 weeks after rolling by collecting terminated (senesced) and non- terminated (non- senesced) sunn hemp from 0.25m2 quadrats. Roll success was most related to sunnhemp height and biomass at time of rolling (R2 = 0.76 P < 0.01 ,0.68 P =0.15). In year one rolling was only successful 80 days after seeding, however in in year two rolling was successful at all seeding dates. More research is needed to understand mechanisms contributing to sunn hemp rolling success.
Tomatoes (Solanum lycopersicum L.) are the largest vegetable crop in the US by dollar value and represent a significant source of income for organic growers in the southeast. High tunnels allow growers to capture more profitable early markets, and the protection they offer provides additional benefits such as extended growing seasons and reduced leaf wetness/foliar disease. Most research on organic high tunnel tomatoes to date focuses on heirloom varieties due to their popularity among organic growers. However, advances in plant breeding in recent decades have yielded hybrids that combine the desirable culinary and aesthetic characteristics of heirlooms with the superior vigor and disease resistance of modern genetics. The objective of this study was to compare the performance and characteristics of such specialty hybrids under organic high tunnel, and organic and conventional field conditions in the Georgia Piedmont region. Two indeterminate cultivars were chosen for this project: ‘Estiva’, a mediterranean variety noted for setting fruit under high temperatures; and ‘Tomimaru Muchoo’, a Japanese pink slicer with thin skin and low acidity. Transplants of both varieties were grown under organic greenhouse conditions for several weeks before planting in organic field, organic high tunnel, or conventional field plasticulture systems. Data loggers were placed in each site to record temperature, relative humidity, PAR, and soil moisture. Fruits were harvested once per week and sorted by USDA marketability standards. Both total and marketable yield were recorded for each plot, as well as disease, pest, and physiological disorder damage. Subsampled fruits from each plot were measured for dimensions, mass, and qualitative aesthetic rating. Fruit and aboveground biomass samples from each plot were harvested, dried, and ground, then analyzed for elemental nutrient content. Soil samples were also taken from each plot prior to planting and after termination for nutrient analysis, pH, and organic matter. In 2023, the highest marketable yields were from the organic high tunnel, with ‘Estiva’ and ‘Tomimaru’ averaging 15491 and 15992 lb/A (FW), respectively; while the conventional field performed better in 2024, with average yields of 11807 (‘Estiva’) and 11611 lb/A (‘Tomimaru’). In 2024, ‘Estiva’ had substantial losses in the high tunnel due to blossom end rot, with 30% of the harvest being marketable as opposed to the 53% obtained from ‘Tomimaru’. These results suggest that under optimal conditions, organic growers can achieve similar yields of high-quality tomatoes to their conventional counterparts through proper application of high tunnels and superior varieties.
Organic lettuce production in hydroponic systems often yields less than conventional production. A previous study from the lab found that organic nutrient film technique (NFT) system with Pre-Empt organic fertilizer contained high concentrations of nitrite ions, which likely induce stress and resulted in lower lettuce yield. To address this toxicity, we conducted a series of studies investigating the effect of reservoir aeration, with the hypothesis that aeration would enhance microbial mineralization of organic nitrogen and reduce the concentrations of phytotoxic compounds such as nitrite and ammonium. In the first study, we aerated NFT reservoir tanks with 15.9 mL/L (2 oz/gal) Pre-Empt organic fertilizer. Aeration increased dissolved oxygen (from 6.4 to 7.8 mg/L) and decreased the ratio of nitrite-nitrogen to nitrate-nitrogen (from 1.1 to 0.2) but did not affect ammonium. As a result, aeration increased yield of ‘Casey’ lettuce by 2.6 times. In the second study, aeration did not increase lettuce growth when the concentration of Pre-Empt fertilizer decreased to 10.6 mL/L (1.4 oz/gal). Furthermore, in the third study, we found cultivar-specific response to the aeration of organic fertilizer. These results suggested that aeration can enhance mineralization of organic nitrogen, reduce root-zone nitrite toxicity and increase lettuce yield at high fertilizer rates and potentially depending on cultivar.
As environmental concerns grow, the horticultural sector is increasingly encouraged to adopt sustainable production practices. Certified Naturally Grown (CNG), established in 2002, offers a peer-reviewed certification rooted in organic principles and aims to foster a strong community network for small-scale producers. This research documents the process of certifying previously unmanaged farmland through the CNG program, offering research-based insights for growers considering certification. The project began with the revitalization of an overgrown, neglected field, focusing first on soil improvement and field preparation to support sustainable crop production. To build soil health and fertility, we planted both summer and fall/winter cover crop mixtures, which helped improve nutrient cycling and restore organic matter. In addition to soil improvement, we developed an integrated pest management (IPM) protocol tailored to our production system and selected OMRI-listed products to meet fertilization, pest, and disease control needs in compliance with CNG standards. To support certification, we also established a record-keeping system to document field activities, input usage, and compliance measures. Finally, we created postharvest handling protocols aligned with CNG principles to help ensure both food safety and product quality from field to market. Soil testing has shown an improvement in soil organic matter, plant-available soil nutrients, and an increase in soil microbial biomass. These gains reflect an improvement in overall soil health and provide a strong foundation for sustainable crop production. Ultimately, this project highlights the planning and steps required for successful CNG certification. The educational tools we create will serve as a guide for producers transitioning to CNG, equipping them with the knowledge to implement sustainable and resilient farming practices.
Momentum for sustainable and organic farming remains strong, driven by concerns for environmental stewardship, health, and social responsibility. As of the 2022 USDA Organic Certified Survey, the number of certified organic operations in the United States grew to 18,263, covering 5,083,623 acres. However, Mississippi continues to have a limited presence, with only 5 certified specialty crop operations as per the USDA Organic Integrity Database. Building on our initial findings, this year’s research continues to investigate the motivations and barriers producers face when adopting organic principles. In year two, we expanded the reach of our survey, pushing the 43-question instrument into all 50 states with the assistance of our partners. The survey remains focused on key challenges including social, environmental, and technical concerns. The core themes from year one—environmental consciousness, financial constraints, and the knowledge-implementation gap—remain prevalent, but we have also observed evolving trends in the responses. Producers continue to cite environmental and market motivations as key drivers. They emphasize the benefits of education on the producer and consumer level as a potential solution. Financial challenges remain a significant barrier, with many producers expressing concerns about the high costs of transition and the economic uncertainty during the process. New insights have emerged regarding the growing role of social networks and community support in facilitating the adoption of organic practices, suggesting that social capital may help mitigate some of the technical and financial challenges producers face. Our case study of a beginning farmer in Calhoun City, Mississippi, highlighted valuable insights into the specific challenges faced by farmers in a region where organic practices are still uncommon. It also highlighted the importance of bridging the knowledge gap and improving support systems for producers. The insights and data garnered have been used to develop a regional database of interested producers. These growers are helping refine recommendations and contribute to the development of targeted programs aimed at supporting the transition to organics including conferences, publication, and other educational efforts. These ongoing experiences continue to guide our understanding of the complexities of transitioning to organic agriculture, offering real-world examples that complement the survey data. As we move forward, we are also exploring how farmers' willingness to adopt organic practices evolves over time and how external factors may influence their decisions. This ongoing research plays a crucial role in advancing the transition to organic certification, ensuring producers are supported in their effort to pursue sustainable practices.
