In a significant advancement for ornamental horticulture, recent studies have demonstrated the efficacy of ethephon substrate drenches in controlling stem elongation in containerized plants. Conducted by researchers at The Ohio State University, these studies reveal that targeted ethephon applications can regulate plant height without compromising health, offering growers a method to produce uniform, high-quality plants for retail markets.
The announcement comes as the horticulture industry seeks innovative solutions to manage plant growth more effectively. Ethephon, a plant growth regulator, is now proving to be a valuable tool in achieving desired plant sizes, particularly in the production of herbaceous perennials and annual bedding plants.
Controlling Stem Elongation in Perennials
One study focused on the application of ethephon drenches to containerized herbaceous perennials. The results were promising, showing that these applications can successfully control plant height, thereby enhancing the uniformity and marketability of the plants. This breakthrough allows growers to maintain plant health while achieving the compact growth necessary for consumer appeal.
Growth Management in Annual Bedding Plants
Meanwhile, a complementary study assessed the impact of ethephon drenches on various annual bedding plants. Researchers found that controlled applications effectively limited excessive growth, resulting in more compact and aesthetically pleasing plants. This discovery offers growers a cost-effective strategy for managing growth in greenhouse and nursery production.
According to W. Tyler Rich, a research associate at The Ohio State University, these findings provide actionable insights for growers aiming to enhance plant uniformity and reduce the need for labor-intensive pruning. The research supports more sustainable and profitable production practices by improving overall crop marketability.
Industry Implications and Expert Insights
The implications of this research extend beyond individual growers to the broader horticulture industry. Effective height and growth control are crucial for both aesthetic quality and operational efficiency. By utilizing ethephon drenches, growers can achieve these goals while also supporting environmental sustainability.
W. Garrett Owen, an extension specialist and assistant professor of sustainable greenhouse nursery systems, emphasizes the importance of these findings. His work focuses on floriculture crop production, plant nutrition, and growth regulation. Owen notes that the research supports responsible use and timing of ethephon applications, which are critical for maximizing benefits in floriculture production.
“As of May 2025, Collate® 2L is the only ethephon product with EPA approval for substrate drench use as well as foliar sprays,” said Rich. “These findings will likely encourage wider adoption among growers seeking to optimize their production processes.”
The Role of the American Society for Horticultural Science
The research, published in the ASHS HortScience electronic journal, underscores the role of the American Society for Horticultural Science (ASHS) in advancing horticultural research and education. Established in 1903, ASHS is one of the most respected professional societies for horticultural scientists worldwide.
Comprised of thousands of members, ASHS represents a diverse cross-section of the horticultural community, including scientists, educators, and industry professionals. The society is dedicated to promoting scientific research and education in all branches of horticulture, addressing practices and problems in areas such as breeding, propagation, and production management.
For those interested in exploring the full studies, they can be accessed through the ASHS HortScience journal website. The research not only highlights the potential of ethephon drenches but also reinforces the importance of continued innovation in horticultural practices.
As the horticulture industry continues to evolve, the adoption of such growth management strategies will be crucial for meeting consumer demands and ensuring sustainable production. The findings from these studies represent a significant step forward in achieving these objectives.
