Navigating substrate transitions in American specialty crop production: challenges and opportunities for research and communication

Authors: BATAME, MICHAEL - University Of Georgia; BAFFOUR-UWAH, DENNIS - University Of Georgia; LAMM, ALEXA - University Of Georgia; LAMM, KEVIN - University Of Georgia; FIELDS, JEB - University Of Florida; Altland, James; SIGNORINI, GUIL - The Ohio State University

Submitted to: Sustainability
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/29/2026
Publication Date: N/A
Citation: N/A

Interpretive Summary: A major challenge for U.S. specialty crop growers is their heavy reliance on peat based soilless substrates. Concerns about environmental impact, rising costs, and long term supply uncertainty have increased pressure to consider alternative materials. Although peat has been widely used for its reliability and consistency, it has been associated with greenhouse gas emissions, ecosystem disturbance, and dependence on foreign supply chains. As demand for containerized production continues to expand, growers have been placed in a position where choosing a sustainable and affordable substrate has become increasingly difficult. To address this problem, a mixed methods study was conducted to understand growers’ experiences with peat, their concerns about transitioning to new substrates, and the types of research and communication resources they need. Surveys and focus groups were used to gather insights from growers across several states. Through this approach, it was revealed that financial cost, material availability, and environmental considerations were the primary factors shaping decisions about substrate changes. It was also shown that growers widely acknowledged the environmental benefits of peat alternatives, but economic feasibility and supply reliability remained the strongest drivers of adoption. Several accomplishments resulted from this work. Key research priorities were identified, including the need for improved irrigation and nutrient management guidelines for new substrates, clear economic comparisons between peat and alternatives, and trials that demonstrate how substitute materials perform under real greenhouse and nursery conditions. Additionally, growers’ preferred ways of learning about new findings were documented. Short online videos, practical websites, podcasts that can be played during work, and hands on demonstrations were favored over longer or less accessible formats. These findings provided a more complete understanding of what growers need in order to make informed decisions about substrate transitions.

Technical Abstract: U.S. specialty crop growers are faced with a myriad of decisions about substrate selec-tion as sustainability, market demands, and resource limitations influence soilless production systems. Peat is a common component in container substrates despite pub-lic concerns about its availability nature, limited supply, and associations with green-house gas emissions and environmental impact; all which have raised grower interest in alternative materials. However, limited research has focused on the experiences, challenges, and research needs of U.S. specialty crop growers related to substrate tran-sitions. The purpose of this mixed-methods study was to explore growers’ key consid-erations, research interests, and preferred communication methods associated with making substrate changes. An online survey and three focus groups were used to gain insights into growers’ experiences, concerns, and perceived impacts of peat replace-ment; research needs; and preferred communication channels. Results indicated finan-cial costs, peat availability, access to peat alternative substrates, and environmental considerations were the main factors influencing potential changes in substrate use. While growers acknowledged environmental and national security benefits of peat al-ternatives, peat availability and cost remained significant influences on replacement decisions. Growers identified key research priorities which would assist in decision making as 1) irrigation and nutrient management strategies, 2) economic performance of alternative substrates, and 3) locally validated trials demonstrating system compat-ibility. They preferred practical communication methods when sharing results includ-ing the use of websites, YouTube videos, in-person meetings, on-farm demonstrations, and short podcasts accessible during routine work hours. The findings implied re-search, outreach, and communication efforts tailored to growers’ operational contexts will support informed substrate transitions.