Eliminate the guesswork with this handy calculator.
Lawn grass fertilizers are primarily nitrogen plus smaller amounts phosphorous and potassium. The three numbers found on each fertilizer package (for example 30-2-3) indicates the percentage of each of these key nutrients. The first number (usually 25 to 35) indicates the percentage of nitrogen. Use the calculator below to see how many pounds of fertilizer you need to apply each year to keep your lawn healthy. In most cases, you would apply one-half to one-third of this amount in each of two or three well-spaced applications during the growing season.
Enter the requested information below, then click Calculate to see the range of amounts of fertilizer you need annually. Remember, too much fertilizer is just as damaging as too little.
Please note: For your convenience, this calculation has been rounded up slightly.
Important reminder: Every effort has been made to ensure the accuracy of this calculation. But before purchasing materials for any project, please check amounts with your suppliers or contractors.