When applying fertilizer, the most important thing to remember is to read and follow the instructions on the fertilizer bag. Proper application will ensure maximum coverage, resulting in a healthy lawn while protecting water bodies.
Calculate Application Rates
To determine the correct amount of fertilizer per 1,000 square feet, divide 100 by the percentage of nitrogen in the bag. For example, a fertilizer with a 15-0-15 label contains 15% nitrogen, 0% phosphorus and 15% potassium. Divide 100 by 15 to get 6.6; this is the number of pounds of slow-release fertilizer needed to apply one pound of nitrogen per 1,000 square feet. This works for any fertilizer product or amount of nitrogen.
Nitrogen application rates vary according to type of turf and location in the state. For more detailed information on calculating application rates, visit University of Florida/IFAS.
Apply Using a Spreader
- Overlap your spread pattern by applying half the fertilizer in one direction and the rest in the opposite direction. This will ensure an even application and avoid the appearance of a striped lawn. Break up any clumps so that the fertilizer will not get clogged in the spreader.
- Turn off the spreader before stopping and when making turns. Then, turn it back on after you have resumed walking. Shut off the spreader when passing over pavement.
- Use a deflection shield when using a spreader near sidewalks, driveways and water bodies. This will avoid spreading fertilizer granules onto impervious surfaces or into water bodies.
- Clean spreader on the lawn, not on the sidewalk or driveway. Fertilizer granules should never be left on impervious surfaces.
Water-in your fertilizer after application with no more than ¼ inch of water. To determine how much this is, perform a catch-can test. Do this by placing empty cat food or tuna cans around the perimeter of your sprinkler or irrigation system and time how long it takes to fill them to this depth (¼ inch). Do this before fertilizing so that you know how long to run the system. This will put the nutrients at root level, where they can be taken up most efficiently. Watering-in with more water than ¼ inch can result in fertilizer leaching more rapidly through the soil.