Do Brand New Lawn Mower Blades need to be Sharpened?

Apart from the smell of freshly cut grass when mowing your lawn, it’s knowing that your mower will give you a nice clean cut to keep your lawn looking great. However, it can be very frustrating if you’re using a blunt mower blade that will hurt your grass and give you an uneven cut.

If you’ve recently bought a lawn mower and you may be wondering if you can start cutting your grass immediately or do you need to sharpen the blades first.

The short answer is no, most new mower blades don’t need to be sharpened because they’re sharpened during the manufacturing process, unless in rare cases where some blades may have a coat of paint in which case you can sharpen the blade, but this paint wears off with use so you don’t need to sharpen the blade.

How Do You know Your Mower Blades Need to be Sharpened?

You must know what to look for so you know when you need to sharpen your mower blades again. This will mostly depend on the number of days and hours you use your mower.

If you use your mower regularly for 30 minutes, you’ll need to sharpen your blades after 40-50 sessions. This means that the more you use the blades, the faster you’ll need to sharpen them.

Some other indicators when to sharpen your blades include looking for dents, major scratches, and small hairline nicks that can be worked on during sharpening.

Another indicator is the grass, if the grass blades don’t have a clean-cut or the tips look torn and ragged, your mower blades need to be sharpened.

Minor dents and cuts can be fixed with sharpening, but big scratches and dents are an indication that you’ll need to replace the blades.

Most homeowners sharpen their mower blades before each mowing season every year, but if you use your mower frequently, you should sharpen your blades twice a year.

After every mowing session, you should always check the blades for any major scratches or nicks.

If there’s any unusual dullness, get the blades sharpened because the more you delay to sharpen your blades, the higher chances you’ll need to replace them.

Problems Caused by Using Dull Mower Blades

If you use a mower with dull blades, the blades will rip through your grass and result in jagged tears on the tips of the blades which will later turn to unattractive yellow or brown color and it also makes your lawn grass more vulnerable to diseases and pests.

A mower with properly sharpened blades will help you achieve a clean cut that is necessary for your grass to remain in a healthy state.

Using sharpened blades is also beneficial to your mower’s engine. It will put a strain on your mower’s engine and you’ll end up using more gas to mow a small area.

Using dull mower blades can also lead to injuries when mowing your lawn.

How Often Should you sharpen your Mower Blades?

Although you don’t need to sharpen new mower blades, you’ll need to sharpen them at the beginning of every mowing season while some people sharpen their blades after 5-10 uses.

If your lawn has a lot of sticks and stones or you have a large yard, you might have to sharpen your blades more often.

Avoid setting the cutting deck of your mower too low so your blades don’t get severely dented or scratched by the stones and rocks on your yard. This will cause you to frequently sharpen them.

How you can Make your Mower Blades Last Longer

Before you begin mowing, you should always clear your lawn of any rocks, stones, toys, big sticks, and branches so you don’t accidentally run them over with the mower and damage the mower blades. If you damage your blades you’ll have to replace them not sharpen them.

Make sure you sharpen the blades frequently, every 20-25 hours of use, and don’t replace the blades if you haven’t sharpened them first.

Learn the correct way to sharpen your mower blades so that you don’t wear off the blades more than is necessary. This means you don’t sand the blades too much each time you sharpen them.

How Long do Mower Blades Last?

Most mower blades last 20-25 hours before they need to be sharpened, but the overall lifetime of most blades is 100-200 hours while some higher quality blades can last up to 400 hours.

Time spent mowing the lawn

Sharpening time

Time to sharpen

30 minutes

40-50 sessions

Every other year

1 hour

20-25 sessions

Once a year

1  ½ hour

13-17 sessions

Once or twice a year


The most obvious benefit to sharpening your mower blades frequently gets to achieve a nice clean cut and help to prevent diseases and pests from taking over your lawn.


Can you sharpen mower blades with a grinder?

Yes, you can use an angle or a bench grinder which is both easier and faster. To sharpen your mower blade, you’ll need a wrench or socket to fit the blade nut.

Can a mower blade be too sharp?

Your mower blade should be very sharp but not razor sharp so you can touch the blade with your fingers without getting cut.

Also read

Where To Buy Used Lawn Mowers Near Me?

Resources and References

Lawn Mower Blade Sharpening How-To Guide

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