18-24-12 Fertilizer
Starter fertilizer18-24-12 is 18% nitrogen, 24% phosphate and 12% potash by weight. To apply 1 lb of nitrogen per 1,000 sq ft, spread 5.56 lbs of product per 1,000 sq ft; a 50-lb bag covers about 9,000 sq ft at that rate.
What 18-24-12 Means
Nitrogen (N)
18%
9 lb per bag
Green color and growth
Phosphate (P₂O₅)
24%
12 lb per bag
Root growth, new seedlings
Potash (K₂O)
12%
6 lb per bag
Stress, drought and cold tolerance
Pounds shown are per 50-lb bag. The N:P:K ratio simplifies to 3:4:2. The remainder of the bag is carrier, filler, and secondary nutrients.
How Much 18-24-12 to Apply
Lawn feeding is measured in pounds of nutrient per 1,000 sq ft. Here's how much product hits each common target.
| Target | Product / 1,000 sq ft | Per acre | 50-lb bag covers | Delivers (N-P-K lb) |
|---|---|---|---|---|
| 0.25 lb N | 1.39 lb | 60.5 lb | 36,000 sq ft | 0.25-0.33-0.17 |
| 0.5 lb N | 2.78 lb | 121 lb | 18,000 sq ft | 0.5-0.67-0.33 |
| 0.75 lb N | 4.17 lb | 182 lb | 12,000 sq ft | 0.75-1-0.5 |
| 1 lb N | 5.56 lb | 242 lb | 9,000 sq ft | 1-1.33-0.67 |
What It's For
A starter fertilizer. The phosphorus supports root development in new seedlings and sod, which is why seeding plans call for it.
When to Use It
At seeding or sodding, applied the same day the seed goes down. Not a routine feed for established lawns.
Before You Spread It
- Several states restrict phosphorus on established lawns unless a soil test shows a need or you're seeding. Check your state's rules before using it as a routine feed.
- Many starter blends coat part of the nitrogen for slow release, which feeds the seedlings less in the first couple of weeks than the bag number suggests. Check the slow-release share.
18-24-12 Products in Our Catalog
18-24-12 Calculator
Enter your lawn size to get the total amount, or change the analysis to check a different bag.
Spread 5.56 lb per 1,000 sq ft, 27.78 lb for 5,000 sq ft (0.56 bags).
Delivers 1 lb N, 1.33 lb P₂O₅ and 0.67 lb K₂O per 1,000 sq ft. Never exceed the label rate.
Common Questions
How much 18-24-12 per 1,000 sq ft?
To deliver 1 lb of nitrogen per 1,000 sq ft, apply 5.56 lbs of 18-24-12 per 1,000 sq ft, or about 242 lbs per acre. Many applications use half that or less, and the product label rate always comes first.
What is 18-24-12 fertilizer used for?
A starter fertilizer. The phosphorus supports root development in new seedlings and sod, which is why seeding plans call for it.
When should I apply 18-24-12?
At seeding or sodding, applied the same day the seed goes down. Not a routine feed for established lawns.
What do the numbers 18-24-12 mean?
They're the percentages by weight of nitrogen (N), phosphate (P₂O₅) and potash (K₂O). A 50-lb bag of 18-24-12 contains 9 lbs of nitrogen, 12 lbs of phosphate and 6 lbs of potash; the rest is carrier and other ingredients.
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