There are approximately 5.5 million acres of home lawns in the state of Florida, most of which are maintained with some level of fertilization throughout the year. Fertilization of home lawns is often believed to be a significant source of nitrates or phosphates reported in ground or surface waters. Because the sandy soils found throughout much of Florida have a tendency to leach nitrates, and due to the abundance of ground and surface water in the state, it is imperative that fertilization regimes be designed to minimize environmental impact. A more thorough understanding of how fertilization and irrigation practices can influence nitrogen leaching and overall turfgrass health may serve to reduce this source of potential contamination. Development of the Florida Green Industries Best Management Practices (BMPs) has raised industry awareness of the need for caution when applying lawn fertilizers to reduce potential environmental impacts. Prior to enforcement of the BMPs under Florida statutes, research data are needed to support the most environmentally sound recommendations for lawn maintenance throughout the state. A five-year, three-location (north, central, and south Florida) project was developed to gain understanding of nitrate and phosphate leaching from warm-season turf (centipedegrass, St. Augustinegrass, zoysiagrass, and bahiagrass) receiving varying application rates of fertilizers and irrigation. Additionally, warm-season turfgrass phosphorus requirements, the influence of nitrogen source and timing on nitrate leaching, and the nitrate leaching potential of fertilizer applied to dormant/semi-dormant grasses are being studied. Results from this work will result in state-wide fertilizer recommendations for maintenance of the highest quality turf with minimal environmental impact. These recommendations will be used by county extension faculty, Florida Department of Environmental Protection, and state or local governmental agencies.