FERTILIZER CALCULATOR

Fertilizer Calculator

Calculate Your Fertilizer Use
Step 1  

Determine the size of your lawn and landscaping (in square feet) to be fertilized and record that number in the box to the right. Please do not use commas (ex. 1500 square feet).

To determine the size of your lawn and landscape, use one of the methods below:

  • Use a tape measure to physically measure the land area to be covered with fertilizer.
  • Informally 'walk' or pace the space to get a less precise gauge of the area to be fertilized.
  • Consider your entire lot size and subtract all impervious areas, such as the driveway and house. If your property contains, or is adjacent to, a body of water or wetland, then remember to leave a 25' fertilizer-free buffer zone. The remaining amount should be the square footage that needs fertilizer.
Step 2  

What rate of nitrogen do you want to put down on your lawn? The Sanibel Fertilizer Ordinance allows a maximum application rate of 1 pound of nitrogen per one thousand square feet (1 lb N/1000 sq.ft.) To apply at this rate, enter 1 in the box to the right. To apply at a lower rate, enter the desired rate in the box, using a decimal equivalent. Do not use fractions (/ sign).

Step 3  

What is the first number in the analysis of your bag of fertilizer?
(ex. 8-2-4) This number corresponds to the percentage of nitrogen (N) in the bag. The second number corresponds to the percentage of phosphorus (P) and the third number, potassium (K). Enter the first number (N) in the box to the right. To comply with the Sanibel Fertilizer Ordinance, this number must be 20 or less.

Remember to make sure that your fertilizer contains at least 50% of the total nitrogen in slow release form and that the percentage of phosphorus (the second number) in your fertilizer is 2% or less.

Apply  pounds of fertilizer to one thousand square feet.
Apply  pounds of fertilizer to cover the entire area indicated in Step 1.
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