Container nursery irrigation practices often result in over-application leading to nutrient leaching and reduced growth. Our objectives were to compare growth and foliar nutrient content for plants under control (19 mm or ¾ inch daily) and 3 daily water use (DWU) based irrigation treatments; determine DWU of 14 woody plants; and classify plants into irrigation groups. Average DWU ranged between 2.1 and 22.0 mm. Most DWU-based treatments resulted in less water applied than the control, yet plant growth was not reduced. Lower foliar P and K concentrations were found for several taxa in control versus DWU treatments.
A national team of scientists is working to encourage use of alternative water resources by the nation’s billion-dollar nursery and floriculture industry has been awarded funds for the first year of an $8.7 million, five year US Department of Agriculture – National Institute of Food and Agriculture –Specialty Crop Research Initiative competitive grant.
The team will develop and apply systems-based solutions to assist grower decision making by providing science-based information to increase use of recycled water. This award from the NIFA’s Specialty Crop Research Initiative is managed by Project Director Sarah White of Clemson University. She leads a group of 21 scientists from nine U.S. institutions.
Entitled “Clean WateR3 - Reduce, Remediate, Recycle – Enhancing Alternative Water Resources Availability and Use to Increase Profitability in Specialty Crops”, the Clean WateR3 team will assist the grower decision-making process by providing science-based information on nutrient, pathogen, and pesticide fate in recycled water both before and after treatment, average cost and return-on investment of technologies examined, and model-derived, site specific recommendations for water management. The trans-disciplinary Clean WateR3 team will develop these systems-based solutions by integrating sociological, economic, modeling, and biological data into a user-friendly decision-support system intended to inform and direct our stakeholders’ water management decision-making process.
The Clean WateR3 grant team is working with a stakeholder group of greenhouse and nursery growers throughout the United States.
For example, at the University of Florida graduate student George Grant is collecting data on removal of paclobutrazol, a highly persistent plant growth regulator chemical, from recirculated water using granular activated carbon (GAC) filters. This is being done in both research greenhouses and in a commercial site. The GAC filters can remove more than 90% of chemical residues, and are proving to be a cost-effective treatment method.