Abstract

Many states throughout the United States are now concerned about the impact of non-point source pollution on the declining quality of water in their watersheds. In 1998, the state of Maryland adopted one of the toughest nutrient management planning laws in the nation, requiring virtually all agricultural operations to write and implement nitrogen (N) and phosphorus (P) based management plans by December 31, 2002. The nursery and greenhouse industries are faced with a complicated task to write these nutrient management plans, since these operations grow a large number of plant species utilizing a range of fertilization and irrigation strategies. A nutrient management planning strategy has been identified that will provide an assessment of nutrient loss potential from a wide variety of production scenarios, identify the specific factors that contribute most to nutrient leaching and runoff, and enable targeted best management practices to be implemented to reduce the risk of nutrient run-off.