Wondering how much fertilizer to put on your grass? Use this fertilizer calculator to help you figure out how much fertilizer you need to put down to give your grass the amount of nitrogen that it needs to thrive.
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🧮Fertilizer Calculator:
In general, you should apply 0.5 to 1 lb of nitrogen per 1,000 square feet of lawn about four times a year. If doing a fall nitrogen blitz, applying 0.5 of nitrogen per 1,000 square feet every 1-2 weeks in the fall is recommended.
Most lawn fertilizers are formulated to cover either 5,000 or 7,500 square feet. Always check the bag and read the label of the product you’ve selected.
It’s crucial to apply the correct amount of fertilizer based on the total square footage of your lawn, so make sure to use the fertilizer calculator above! Any leftover fertilizer can be stored in a cool, dry place for future use.
For even coverage, apply half the recommended rate in one direction, then the other half in a perpendicular direction.
Pro Tip: Make sure to sweep or blow any fertilizer off sidewalks and driveways back onto the lawn to help protect your community’s water quality.
Calculator Formula
The above formula is used in our fertilizer calculator. Let’s break it down:
- Lawn Size (in square feet): This is the total area of your lawn.
- Nitrogen Rate (in pounds per 1,000 square feet): This represents how many pounds of nitrogen you want to apply per 1,000 square feet of lawn.
- N Value: This is the percentage of nitrogen (N) in the fertilizer which is listed on the NPK label on the fertilizer.
Example:
If you have:
- A lawn size of 5,000 square feet,
- A nitrogen application rate of 1 pound per 1,000 square feet,
- And a fertilizer with an NPK value of 21-4-12 (meaning 21% nitrogen),
This means you would need 23.81 pounds of fertilizer to cover the 5,000 square feet of lawn at the desired nitrogen rate of 1 pound per 1,000 square feet.
Nitrogen Fertilizer Application
The lawn fertilizer calculator above is assuming you are using a solid fertilizer made of prills. The best way to apply this type of fertilizer evenly to your lawn is by using a hand or push spreader.
Here’s what we’d recommend:
👉BUY – Scotts Whirl Hand-Powered Spreader
👉BUY – Scotts Broadcast Push Spreader
These spreader types are excellent methods to put down your fertilizer.
Not sure how to pick the best lawn fertilizer? Check out this guide – How to Choose The Best Lawn Fertilizer.