There are literally thousands of fertilizers and fertilizer/pesticide combinations available to homeowners and professionals. Therefore, we can’t recommend how many pounds of fertilizer to apply, but rather we must recommend fertilization rates in pounds of nitrogen per thousand square feet or lbs N/1000ft 2 . Calculating the amount of fertilizer to purchase and apply is a two step process. Once you determine the fertilizer you want and the recommended rate of N/1000 ft 2 , it is then a two step process to determine how much of that fertilizer to purchase and apply to your specific turf area:
Step 1. Calculating the amount of fertilizer/1000 ft 2 : |
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Desired rate in lbs N |
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% nutrient |
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Total fertilizer needed |
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Step 2. Calculating the amount of fertilizer to treat the entire turf area: |
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Total fertilizer needed |
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Area to be treated in ft 2 |
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lbs fertilizer needed to treat the area |
For example, how much fertilizer do you need to apply a 16-8-8 fertilizer at 0.75 lbs N/1000 ft 2 to an 8000 ft 2 lawn?
Step 1. Calculating the amount of 16-8-8/1000 ft 2 : |
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0.75 lbs N |
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.16 N |
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4.69 lbs 16-8-8 |
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Step 2. Calculating the amount of 16-8-8 to treat the entire 8000 ft 2 turf area: |
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4.69 lbs 16-8-8 |
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8000 ft 2 |
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37 lbs 16-8-8 needed to treat an 8000 ft 2 lawn |
ou’ll need 37 pounds of 16-8-8 to treat the 8000 ft 2 lawn at 0.75 lbs N/1000 ft 2 . More information of choosing fertilizers, fertilization schedules, calibrating spreaders, and more can be found in AY-22: Fertilizing Established Lawns.