How Much Fertilizer Per 1,000 Sq Ft of Lawn

For 1 lb nitrogen per feed, how much fertilizer per 1000 sq ft is about 4 lb of a 24 percent nitrogen product or about 3.5 lb of a 29 percent nitrogen product. The exact amount changes with the nitrogen percent on the bag, so use the rate for your product, not one fixed bag weight for every lawn.

That answer works because rates are set in nitrogen first and product second. The bag gives the nitrogen percent. Divide the nitrogen per feed by that percent to get the product per 1,000 sq ft. Then scale it to any lawn size by multiplying by the number of 1,000 sq ft units in the lawn.

How Much Fertilizer Per 1000 Sq Ft at the Standard Rate

The standard nitrogen per feed on the verified calculator page is around 1 lb per 1,000 sq ft. That is the amount of actual nitrogen in one feed, not a product weight. The product weight depends on how much nitrogen is in each pound of the product you buy.

A 24 percent product contains 0.24 lb nitrogen in every 1 lb of product. To deliver 1 lb nitrogen, you need 1 divided by 0.24, which is 4.17 lb, rounded on the page to about 4 lb per 1,000 sq ft. A 29 percent product needs 1 divided by 0.29, which is 3.45 lb, rounded on the page to about 3.5 lb per 1,000 sq ft.

The difference grows as the lawn grows. On a 5,000 sq ft lawn, the 24 percent product needs 20.8 lb per feed, while the 29 percent product needs 17.2 lb, a difference of 3.6 lb for the same nitrogen. On a 10,000 sq ft lawn, the difference is 7.2 lb. Use the calculator at https://theplantcalculator.com/lawn-turf/lawn-fertilizer-calculator/ to check your own product and lawn size.

Nitrogen Per Feed Is Not Product Per Feed

The most common error is treating the nitrogen rate and the product rate as the same number. They are not. Nitrogen per feed is the nutrient amount. Product per feed is the bag weight that carries that nutrient amount. A bag is mostly filler and other nutrients as well as nitrogen, so the product weight is always higher than the nitrogen weight.

The formula is product rate equals nitrogen per feed divided by nitrogen percent. Penn State Extension teaches the same division, giving 3.8 lb of a 26 percent product per 1,000 sq ft for 1.0 lb nitrogen. A higher nitrogen percent means less product for the same nitrogen, and a lower percent means more product.

Product Rate Per 1000 Sq Ft at 1 Lb Nitrogen

The table below gives the product per 1,000 sq ft for 1 lb nitrogen per feed at several nitrogen percentages. The 24 percent and 29 percent rows use the page FAQ figures, shown rounded as the page shows them. The other rows are computed from the verified formula, 1 lb nitrogen divided by the nitrogen percent as a decimal, and are labelled computed.

Nitrogen percent	Product per 1000 sq ft for 1 lb nitrogen	Source
10 percent	10.0 lb	Computed
16 percent	6.3 lb	Computed
20 percent	5.0 lb	Computed
24 percent	4.0 lb	Page FAQ, rounded from 4.17 lb
26 percent	3.8 lb	Computed, agrees with Penn State Extension
29 percent	3.5 lb	Page FAQ, rounded from 3.45 lb
32 percent	3.1 lb	Computed
46 percent	2.2 lb	Computed

Read the table from the nitrogen percent on your bag. For a 21 percent product, 1 divided by 0.21 is 4.8 lb per 1,000 sq ft. For a 28 percent product, 1 divided by 0.28 is 3.6 lb. A 10 percent product needs 10.0 lb, while a 46 percent product needs only 2.2 lb, a difference of concentration, not quality.

How to Work Out Your Own Rate in Three Steps

You need the lawn area in square feet, with beds and paths left out, the nitrogen percent from the bag, and the nitrogen per feed, around 1 lb per 1,000 sq ft on the verified page.

Step one is to write the nitrogen percent as a decimal. A 24 percent product becomes 0.24, and a 29 percent product becomes 0.29.

Step two is to divide the nitrogen per feed by that decimal. At the standard feed, 1 divided by 0.24 is 4.17 lb per 1,000 sq ft, about 4 lb as the page states it. For a 29 percent product, 1 divided by 0.29 is 3.45 lb, about 3.5 lb.

Step three is to scale that unit rate to the whole lawn. Multiply it by the lawn area divided by 1,000. A 24 percent product on a 5,000 sq ft lawn gives 20.8 lb per feed, matching the page imperial example, which works out to a 24 percent product. That figure is derived, not page stated. As a check, 4.17 times 0.24 is 1.00 lb nitrogen.

Metric Companion Table Per Square Metre

The metric standard on the verified page is 5 g nitrogen per square metre per feed, a rounded form of the imperial standard, since 1 lb nitrogen per 1,000 sq ft converts to 4.88 g per square metre. The formula is the same in metric units.

Nitrogen percent	Product per square metre for 5 g nitrogen	Source
10 percent	50.0 g	Computed
20 percent	25.0 g	Computed
24 percent	20.8 g	Computed
29 percent	17.2 g	Computed
32 percent	15.6 g	Computed

To use the table, multiply the rate by the lawn area in square metres, then divide by 1,000 to get kilograms. A 400 square metre lawn at 20.8 g per square metre needs 8.32 kg per feed, close to the page worked example of 8.17 kg, where the page used 4.9 g nitrogen rather than the rounded 5 g standard here. A 400 square metre lawn is about 4,306 sq ft, not 5,000 sq ft, so the two page examples are separate.

Worked Examples for Common Lawn Sizes

The examples below are computed from the verified formula at the standard 1 lb nitrogen per feed, except where the page imperial example is named.

A 2,500 sq ft lawn with a 24 percent product needs 10.4 lb per feed, and with a 29 percent product it needs 8.6 lb. If bags weigh 15 lb, each feed needs one bag, rounded up.

A 5,000 sq ft lawn with a 24 percent product needs 20.8 lb per feed, matching the page imperial worked example. With a 29 percent product, it needs 17.2 lb. If bags weigh 15 lb, each feed needs two bags, rounded up. The page yearly total for that example is 83.3 lb, six 15 lb bags a year, which works out to 4 feeds a year. The 4 feeds figure is derived, not page stated.

A 10,000 sq ft lawn with a 24 percent product needs 41.7 lb per feed, and with a 29 percent product it needs 34.5 lb. If bags weigh 15 lb, each feed needs three bags, rounded up.

What a Lower Feed Does to the Rate

Some lawns are fed at 0.5 lb nitrogen per 1,000 sq ft in a single feed. The product rate falls in direct proportion. At 0.5 lb nitrogen, a 20 percent product needs 2.5 lb per 1,000 sq ft, a 24 percent product needs 2.1 lb, and a 29 percent product needs 1.7 lb. In metric units, at 2.5 g nitrogen per square metre, a 24 percent product needs 10.4 g per square metre, half the 20.8 g in the metric table. The yearly nitrogen need for cool season lawns on the verified page is 2 to 4 lb per 1,000 sq ft a year, spread across feeds. The number of feeds belongs to another blog in this batch.

How to Read the Bag Label for This Calculation

Only the first number in the NPK analysis matters here. That number is the nitrogen percent by weight. A bag marked with 24 as the first number is a 24 percent product, and a bag marked with 29 is a 29 percent product. The second and third numbers give the phosphate and potash percentages. They do not change the product rate for a nitrogen target. The full meaning of the three numbers belongs to another blog in this batch. Read the guaranteed analysis panel, not the front marketing claim, which may state coverage for a particular spreader setting under the maker feeding plan. Use the nitrogen percent with the formula above, and use the calculator at https://theplantcalculator.com/lawn-turf/lawn-fertilizer-calculator/ to confirm the result.

Common Mistakes

Mistake one is using the bag weight as the nitrogen weight. A 20 lb bag of a 24 percent product contains 4.8 lb nitrogen, not 20 lb nitrogen.

Mistake two is dividing by the percent instead of the decimal. Dividing 1 by 24 gives 0.04 lb, far too low. Dividing 1 by 0.24 gives 4.17 lb.

Mistake three is applying the per 1,000 sq ft rate to the whole lawn without scaling. The total for a 5,000 sq ft lawn is 4.17 times 5, which is 20.8 lb, not 4.17 lb.

Mistake four is reading the coverage on the bag as a nitrogen rate. Bag coverage is an area claim for a stated product amount, not a nitrogen rate.

Mistake five is feeding a dormant or drought stressed lawn at the standard rate. The verified page states that dormant or drought stressed lawns should not be fertilized.

Mistake six is rounding bags down. A feed that needs 20.8 lb of product from 15 lb bags needs two bags, not one bag plus a guess. Buying counts are always rounded up to whole bags.

FAQs

Q: How much fertilizer per 1000 sq ft of lawn at the standard feed?

A: About 4 lb of a 24 percent product or about 3.5 lb of a 29 percent product per 1,000 sq ft for 1 lb nitrogen per feed.

Q: How do I work out the product rate for a product that is not in the table?

A: Divide the nitrogen per feed by the nitrogen percent as a decimal. For a 21 percent product, 1 divided by 0.21 is 4.8 lb per 1,000 sq ft.

Q: Why does a stronger product need less weight per 1,000 sq ft?

A: A stronger product carries more nitrogen in each pound. A 29 percent product carries 0.29 lb nitrogen per pound, while a 24 percent product carries 0.24 lb.

Q: How much product does a 5,000 sq ft lawn need per feed?

A: At 1 lb nitrogen per feed with a 24 percent product, 20.8 lb per feed, which matches the page imperial worked example. With a 29 percent product, it needs 17.2 lb.

Q: What is the metric rate per square metre?

A: The page standard is 5 g nitrogen per square metre per feed. A 24 percent product needs 20.8 g of product per square metre, and a 29 percent product needs 17.2 g.

Q: Can I put down too much fertilizer per 1,000 sq ft?

A: Yes. Excess nitrogen can scorch grass, encourage disease, and wash into waterways. Do not fertilize a dormant or drought stressed lawn.