A new study by the Lamm Lab has been published in Horticulturae. titled Using the Diffusion of Innovations Theory to Explore U.S. Horticultural Industry Stakeholders’ Adoption of Alternative Substrates. Authors include Dennis Baffour-Awuah, Michael Batame, Dr. Alexa J. Lamm, Dr. Kevan W. Lamm, Dr. Jeb Fields, Dr. James Altland, and Dr. Guilherme Signorini. The study is part of the Soilless Substrate Science project, for which the Lamm Lab leads the social science component. The soilless substrate science project is made possible by the USDA National Institute of Food and Agriculture (NIFA) through Award #:2024-51181-43290.
Background
For decades, peat has been a dominant component of soilless substrates in horticultural production systems because of its favorable physical and chemical properties. Despite its widespread use, concerns about peat extraction and long-term availability have generated increased attention from policymakers, environmental organizations, researchers, and industry stakeholders. Peatlands function as important carbon sinks, storing substantial quantities of carbon accumulated over thousands of years. As a result, researchers and industry stakeholders have increasingly explored sustainable alternative substrate materials to reduce reliance on peat and expand the range of growing media available to producers.
The study explored the benefits and challenges U.S. horticultural industry stakeholders associate with adopting peat-alternative substrates. The researchers also examined these considerations through the five perceived innovation attributes of Diffusion of Innovations theory: relative advantage, compatibility, complexity, trialability, and observability. This approach helped provide a better understanding of stakeholders’ adoption considerations and how the findings could inform future Extension, research, and science communication efforts.
Using a qualitative approach, the researchers analyzed data from three focus groups involving 35 horticultural industry stakeholders, including specialty crop growers, research scientists, crop consultants, and professionals in other horticultural industry roles who have an interest in soilless substrates and experience using peat or other substrate materials in specialty crop production systems.
The study was guided by three research questions:
- What benefits do horticultural industry stakeholders associate with adopting peat-alternative substrates?
- What challenges do stakeholders in the horticultural industry face in adopting peat-alternative substrates?
- How are the five perceived innovation attributes reflected in participants’ adoption considerations?
The Findings
The participants identified several characteristics they considered advantageous when evaluating peat-alternative substrates. They emphasized that successful alternatives should provide performance comparable to peat while supporting environmental sustainability. Economic viability and reliable supply were also important considerations, particularly for determining whether alternative substrates would be practical for commercial production.
When discussing challenges, participants described substrate adoption as more than simply finding a replacement for peat. They emphasized the need to balance operational requirements, production consistency, and financial realities while navigating uncertainty associated with limited knowledge, insufficient performance evidence, and unfamiliar substrate materials.
The researchers then interpreted these findings using the five perceived innovation attributes of DOI theory:
- Relative advantage was discussed predominantly positively, reflecting considerations such as substrate performance, economic viability, and environmental sustainability.
- Compatibility supported adoption when alternatives fit existing production systems, equipment, and sourcing practices.
- Complexity was discussed predominantly negatively, particularly when alternatives required changes to irrigation, nutrient management, equipment, or established production practices.
- Trialability highlighted the value of small-scale testing before implementing alternatives across commercial operations.
- Observability showed the potential value of seeing other growers successfully use peat-alternative substrates in reducing uncertainty.
Implications
The researchers emphasized that the findings provide practical implications for future research, Extension programming, and industry efforts related to peat-alternative substrates. Future research could evaluate peat alternatives under long-term commercial conditions, with particular attention to consistency, cost-effectiveness, and suitability across specialty crop production systems. Demonstration trials, field days, and decision-support tools could also be evaluated as approaches to help growers assess alternative substrates under commercial conditions and better understand associated irrigation, fertility, and management requirements. The researchers also recommended further examination of how collaboration and communication among researchers, Extension professionals, industry stakeholders, and growers may reduce uncertainty and influence actual adoption decisions.
