Smarter watering, healthier plants
Delivering practical skills for irrigation and tissue culture success
Paul Fisher, Extension specialist in floriculture and greenhouse production at the University of Florida in Gainesville, Florida, will present two sessions at the Great Lakes Fruit, Vegetable and Farm Market EXPO and Michigan Greenhouse Growers EXPO: Train Your Staff How to Water and Success With Tissue Culture Plants.
Fisher manages two university and industry groups, undertaking applied research and grower training for greenhouse floriculture production and water conservation. Working in a network of operations across the U.S., Fisher conducts on-site research with growers, visiting greenhouse operations to run experiments on a commercial scale and provide feedback to keep research current and relevant.
Train Your Staff How to Water — (Paul Fisher and Nelda Hernandez)
Wednesday, Dec. 10, 2025
2:40 p.m. EST to 3:30 p.m. EST
Through Fisher’s training modules, he discovered one of the most important training needs among greenhouse growers is how to water plants effectively.
“By far, the most common issue we’ve seen is overwatering. When people overwater, several different things can happen, such as root diseases and plant losses,” Fisher said. “When you overwater, you wash out fertilizer and pesticides into the environment, increasing the cost of those inputs, reducing their effectiveness and potentially contaminating the environment.”
Fisher also notes that plant health and size can vary if growers don’t water optimally. When growers do not water properly, this increases the cost of production, including labor. Greenhouse staff will need to replace unhealthy plants and sort out the different plant sizes.
During this session, Fisher will discuss a program through Greenhouse Training Online called Professional Irrigator, which offers a blend of online and on-site practical lessons for growers.
“Our approach is to certify growers as trainers for their own staff. With Greenhouse Training Online, growers can choose to become certified trainers or utilize our free resources on YouTube and develop their own program,” Fisher said.
Through the University of Florida, Greenhouse Training Online provides videos and quizzes in both English and Spanish.
“You need growers to be able to train their own people in the practical how-to activities within their own greenhouse nursery,” Fisher said. “Our program is a blend of the university supporting growers to train their own staff on how to water to ultimately have consistent quality, fewer losses and greater staff satisfaction.”
According to Fisher, over 100 growers are now certified trainers through the help of Greenhouse Training Online.
“Greenhouse Training Online is designed to empower growers to be more effective at training their staff. We’re really trying to standardize the knowledge level and practices of the staff so growers can create an effective crop plan,” Fisher said.
Success With Tissue Culture Plants (Paul Fisher and Isabella Violante, Walters Gardens)
Wednesday, Dec. 10, 2025
10:30 a.m. EST to 11:20 a.m. EST
Some of the highest-value crops that growers produce start from tissue culture. Tissue culture plants are considered very fragile, and when purchasing young plants, growers transfer them into trays and pots. This process often results in a higher percentage of losses compared to starting from seed or cuttings.
“It’s really important to know how to handle, acclimate and grow tissue culture plants so they have greater rooting success and fewer plant losses,” Fisher said. “At the university, we focus on aspects of managing the climate, such as light and temperature, relative humidity and irrigation.”
During the session, attendees will learn about these environmental parameters, watering irrigation tips and more. Isabella Violante from Walters Gardens in Zeeland, Michigan, will provide a grower’s perspective on how to effectively manage tissue culture plants.
The Great Lakes Fruit, Vegetable and Farm Market EXPO and Michigan Greenhouse Growers EXPO takes place Dec. 9 to 11, 2025 at DeVos Place in Grand Rapids, Michigan.
Learn more about this year’s show at glexpo.com.
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