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Home HortTechnology Urban Fertilizer Bans in Florida Could Have Unintended Consequences
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GAINESVILLE, FL--Eutrophication, the increase in growth of algae and nuisance aquatic plants that results from nutrient enrichment of fresh and coastal waters, is an escalating problem. The process, largely the result of human activities, causes degradation of ecosystems and in turn affects the quality of water available for drinking, recreation, fishing, and irrigation. The impact of urban nutrient sources is becoming a widespread question as officials try to address eutrophication of urban water bodies.

In Florida and throughout the United States, scientists are working to find solutions to these serious environmental concerns. George Hochmuth from the Department of Soil and Water Sciences at the University of Florida and lead author of a this report, knows that degraded inland and coastal water quality is a critical statewide concern in Florida and other states. "Coastal and urban eutrophication is an increasing problem and is related to land-based activities. Sources of nutrients involved with eutrophication are numerous and the interactions with harmful algal blooms are complex," Hochmuth said. Alarming statistics have shown that harmful and toxic algal blooms resulted in greater revenue losses for businesses on Florida's panhandle than other environmental events such as tropical storms and rains.

To assess the scope of the problem and related research, Hochmuth and colleagues published an extensive review of the scientific literature in HortTechnology. "Regulators are asking about the best approach to controlling urban pollution. They want to know if banning fertilizer in the growing season would achieve the desired environmental protection and whether there are any potential unintended consequences associated with removing fertilizer from turfgrass growing in the summer months," the report said. In some Florida communities, for example, local ordinances mandate a summer (or "wet season") fertilizer ban or "blackout".

While investigating scientific information about turfgrass fertilization practices that correspond with the timing of these summer fertilizer bans, the team uncovered evidence that best management practices--when not followed correctly--can reduce turf density in home lawns. "The research points to potential unintended consequences of increased nutrient losses from urban landscapes, particularly turfgrass, when proper, recommended fertilization and irrigation practices are not followed," the researchers said. "Healthy, well-managed turfgrass has been shown to minimize nutrient loses to leaching and runoff. Practices that reduce turfgrass health and ground coverage may lead to increased nutrient losses."

Continued public education efforts are the key to informing homeowners about the ways in which landscape practices can impact water quality, the scientists noted. "Continuing the effort to educate the public about the best landscape maintenance practices, as determined by scientific research, is critical to minimizing nutrient losses."

The report recommends that before fertilizer bans are fully adopted, further research should be conducted to demonstrate any potential environmental benefits of the bans.


The complete study and abstract are available on the ASHS HortTechnology electronic journal web site:

Founded in 1903, the American Society for Horticultural Science (ASHS) is the largest organization dedicated to advancing all facets of horticultural research, education, and application. More information at


Original Article:

Potential Unintended Consequences Associated with Urban Fertilizer Bans in Florida--A Scientific Review
George Hochmuth, Terril Nell, J. Bryan Unruh, Laurie Trenholm, and Jerry Sartain
HortTechnology 22:600–616. [Abstract][Full Text][PDF]

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