Our current research covers a wide range of areas of importance to the floriculture industry
Charlie Smith is a PhD student at Michigan State University. He is researching how to prevent the development of purple foliage in vegetatively propagated crops such as petunia. As more young growers replace high-pressure sodium (HPS) lamps and adopt light-emitting diode (LED) fixtures as their main source of supplemental lighting, they are reporting that some unrooted cuttings grown under these high-intensity LEDs are developing purple and chlorotic foliage. Preliminary work suggests that the purpling is occurring from a combination of the high-energy, short wavelength blue light being emitted onto the crop, and the drop in plant temperature that occurs when switching from HPS lamps to LEDs. From this work, we hope to develop environmental protocols that growers utilizing LEDs can employ to prevent or mitigate the onset of this foliage discoloration.
Last updated: 26 Sep 2025
Further information: Roberto Lopez and Erik Runkle (rglopez@msu.edu)
Carly Anderson (Ph.D. student at UF) is researching how new technologies can strengthen Extension programs, and specifically greenhouse propagation practices. Carly has developed a prototype chatbot focused on cuttings and stock plants that will support an upcoming online greenhouse training course. With the rapid growth of generative AI and limited guidance for Extension programs, her work also aims to establish practical best-practice guidelines for responsible use in extension. In addition, Carly is analyzing climate and irrigation data from sensors, including leaf wetness sensors, to improve propagation irrigation strategies. Sensor data will be integrated into dashboards and grower reports to support clearer interpretation of greenhouse and vertical indoor propagation environments.
Last updated: 24 Sep 2025
Further information: Paul Fisher, University of Florida (pfisher@ufl.edu)
Nelda Hernandez (Ph.D. student at UF) is assessing training needs in the horticultural workforce. She developed the “Professional Irrigator” grower training series (https://hort.ifas.ufl.edu/training), which combines online and hands-on activities on various irrigation topics. The goal of this training is to standardize staff training in irrigation practices to ensure high quality plants and effective water use. In addition to the human aspects of irrigation, Nelda is researching high-tech automation of irrigation for seedling plugs. Currently, irrigation decisions rely on subjective methods such as time-based schedules, grower experience, and tray weight. While helpful, these methods are not always objective or practical for commercial use. By using climate sensors to monitor air and leaf temperature, moisture levels, imaging with thermal and RGB cameras and by measuring physiological variables, Nelda’s research aims to establish objective parameters for irrigation decisions. This project will eventually expand to include sensors and cameras mounted on irrigation booms in greenhouses to map water needs and trigger automated irrigation events.
Last updated: 23 Sep 2025
Further information: University of Florida (Dr. Paul Fisher, pfisher@ufl.edu)
Dharti Thakulla (PhD student) is researching the implementation of ozone and cold plasma technologies for water treatment. Microbial contamination of the nutrient solution is a key challenge faced by growers using recirculating systems or surface water supplies. She and undergradute Heather Buss are running a series of experiments on dose response for cold plasma and ozone for controlling biofilm organisms and Pythium, in addition to effects on compatibility with micronutrient fertilizers and beneficial microbes.
Last updated: 23 Sep 2025
Further information: Dr. Paul Fisher, University of Florida (pfisher@ufl.edu)
Sean Tarr is a research technician at Michigan State University and is studying how a defined number of short-day cycles influences flowering time, and flower quantity and morphology in floriculture crops such as dahlia and begonia. Dahlia is a facultative short-day plant: while short days accelerate flowering, prolonged exposure also promotes tuber formation, which can be undesirable in production. There may be a critical cycle number where a limited short-day exposure hastens flowering without inducing tuberization. Identifying this threshold could provide growers with a strategy to improve crop timing during spring to mid-summer in dahlia, tuberous begonia, and other photoperiod-sensitive crops, including ornamental grasses.
Last updated: 23 Sep 2025
Further information: Dr. Roberto Lopez, Michigan State University (rglopez@msu.edu)
Destany Westlake (M.S student) is researching heavy metal uptake and contamination in hemp. Heavy metals are heavily regulated by the EPA as a contaminant and pose a significant threat to hemp growers because of its tendency to accumulate heavy metals. Destany is developing methods to determine the plant-availability of heavy metals in crop inputs, and reduce the risk of plant uptake of heavy metals with substrate amendments such as peat, lime, and biochar.
Last updated: 27 Aug 2025
Further information: Dr. Paul Fisher, University of Florida (pfisher@ufl.edu)
Jacob Muller (M.S. student) is researching energy and economics in vertical indoor propagation of young plants under sole-source LED lighting. This technology is being used by leading growers to consistently produce hard-to-root transplants such as tissue culture plants.
Last updated: 27 Aug 2025
Further information: Dr. Paul Fisher, University of Florida (pfisher@ufl.edu)
Shara Carolina Ortiz Carvajal, Master's student is researching prevention of rapid leaf collapse in Chrysanthemum. Cut flower chrysanthemum leaves can become chlorotic and necrotic during the first week in the vase. The cause of this phenomenon is currently unknown. We are evaluating pre-harvest and postharvest strategies to reduce the occurrence of symptoms. Green-flowering cultivars are the most susceptible, however many cultivars display symptoms. We have ruled out the possibility of bacteria as the cause, and we have also eliminated water relations as a causal factor.
Last updated: 8 Oct 2022
Further information: Jim Faust, Clemson University (jfaust@clemson.edu)
Josselyn Gabriela Calidonio, M.S. Student at Clemson University, is researching effectiveness of different disease management agents for Botrytis in floriculture crops. Gray mold caused by Botrytis cinerea is a major disease that affects many floriculture crops. Weekly, preventative fungicide applications have been the main strategy for Botrytis management, but this lead to fungicide resistance development. The use of antagonistic fungi and bacteria has become popular and offers a sustainable disease management option. In our project, we are screening 20 compounds, such as biological control agents, plant nutrients, plant extracts, and systemic acquired inducers to observe their effectivity against gray mold in petunias, roses and gerbera daisies.
Last updated: 8 Oct 2022
Further information: Jim Faust, Clemson University (jfaust@clemson.edu)
Melissa Muñoz Agudelo, Ph.D. Candidate at Clemson University, is researching management of Botrytis blight in roses. Roses represent a very important commodity in floriculture. Botrytis cinerea is a fungal pathogen that causes Botrytis blight and threatens rose profitability. Disease management relies often on fungicide applications; however, fungicide resistance development jeopardizes the efficacy and sustainability of this strategy. Prolonged periods of high humidity and moderate temperatures favor disease development, and these conditions are very often present in the greenhouses. These facts underscore the importance of developing alternative management strategies. Current research focuses on evaluating pre-and post-harvest applications of calcium in roses considering the role of calcium in enhancing the strength of the plant cell and mediating plant defense responses and secondary metabolites release against Botrytis cinerea.
Last updated: 8 Oct 2022
Further information: Jim Faust, Clemson University (jfaust@clemson.edu)