Fertilizer Calculator
Tip: Water your lawn within 24 hours of fertilizing to activate the nutrients and prevent burn.
How to Calculate Fertilizer Amounts
Measure your lawn area in square feet.
Choose the fertilizer type based on your lawn's current needs.
The calculator applies the recommended nitrogen rate per 1,000 sq ft.
Results show total pounds needed and number of bags to buy.
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Frequently Asked Questions
A general rule is 1 lb of actual nitrogen per 1,000 sq ft per application. Most homeowners apply fertilizer 2–4 times per year. This calculator uses standard N-P-K ratios to determine the total product amount needed.
Starter fertilizer has a higher phosphorus content (the middle number in N-P-K) to promote root development in new grass. Use it when seeding a new lawn or laying sod. Switch to regular fertilizer after the lawn is established.
Apply winterizer fertilizer in late fall, typically October–November, after the grass has stopped growing above ground but before the ground freezes. This helps roots store energy for winter survival and spring green-up.
Yes. Over-fertilizing can burn your grass, cause excessive top growth at the expense of roots, and pollute waterways. Always follow recommended rates and never apply more than the label directs.
Apply fertilizer to dry grass, then water it in within 24 hours. Don't apply before heavy rain — the fertilizer can wash off before being absorbed. Light rain after application is fine and can help water it in.