When it rains, most homeowners think about the benefits to their landscape. Fewer think about where excess water goes after it leaves their property.
In urban and suburban areas, heavy rainfall and excess irrigation often flow into streets, storm drains, washes, streams, rivers, and lakes. Unlike wastewater from homes, stormwater typically receives little or no treatment before entering the environment.
As stormwater travels across driveways, sidewalks, landscaped areas, and roads, it can pick up pollutants and carry them into local waterways. These pollutants may include oil, trash, sediment, pet waste, pesticides, and fertilizer nutrients.
One of the most significant concerns is excess nitrogen and phosphorus from fertilizer. While these nutrients are essential for healthy plant growth, they can contribute to water quality problems when they leave the landscape and enter lakes, rivers, or other bodies of water.
The good news is that homeowners can take several simple steps to reduce the risk of nutrient runoff while still maintaining a healthy landscape.
Apply Fertilizer Only Where It Is Needed
Fertilizer is most effective when it is placed where plant roots can access it. Avoid inadvertently spreading fertilizer onto driveways, sidewalks, streets, or other hard surfaces where it can be easily washed away by rain or irrigation.
Avoid Over-Application
More fertilizer does not necessarily produce healthier plants. Applying only the recommended amount helps reduce waste and minimizes the risk of excess nutrients leaving the landscape.
Water Fertilizer Into the Root Zone
Plants absorb nutrients after they dissolve in water and move into the soil. Fertilizer left on dry landscape surfaces are more vulnerable to loss through heat, wind, runoff, or other environmental factors before plants can benefit from it.
Whenever possible, nutrients should be moved into the root zone where roots can access them and where they are less likely to be carried away by surface runoff.
Deliver Nutrients Close to Active Roots
Healthy root systems often extend outward toward the drip line of trees and shrubs. Delivering nutrients near the drip line helps improve nutrient use and reduces the likelihood that fertilizer remains exposed on the landscape surface.
Maintain Healthy Irrigation Practices
Avoid excessive irrigation that creates runoff. Watering deeply and efficiently helps move nutrients into the soil where roots can use them.
Small Changes Can Make a Big Difference
Most homeowners care about both their landscape and the environment. When fertilizer is applied thoughtfully, delivered where plants can use it, and kept out of stormwater runoff, homeowners can support healthier trees and shrubs while helping protect local waterways.
The best place for fertilizer is in the root zone—not in the storm drain.