How many bags of fertilizer does your lawn actually need? The answer depends on your square footage and the product's coverage rate. Punch in both numbers and skip the guesswork.
Lawn Size
sq ft
Bag Coverage
sq ft
Check your bag label
Scenario: Your lawn is 8,000 sq ft and the fertilizer bag covers 5,000 sq ft each.
Result: You need 2 bags per application. With 4 applications per year, plan to buy 8 bags annually.
Divide your lawn area by the bag's coverage rate. An 8,000 sq ft lawn with a 5,000 sq ft bag needs 2 bags per application. Most lawn care programs call for 4 applications per year (early spring, late spring, summer, fall).
Most lawns benefit from 4 applications per year spaced 6-8 weeks apart. Start in early spring when the grass begins growing and make the last application in late fall. Over-fertilizing causes more problems than under-fertilizing.
The three numbers (like 20-5-10) represent the percentage of nitrogen (N), phosphorus (P), and potassium (K). Nitrogen promotes green growth, phosphorus supports roots, and potassium improves disease resistance. For established lawns, high-nitrogen formulas are most common.
Yes. Over-fertilizing burns the grass, causing brown patches, and excess nutrients run off into waterways. Always follow the product label rate. More is not better -- it's worse. Use a calibrated spreader to apply evenly.
Want to learn more before you start your project?
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