How (and when) to Sharpen Your Mower Blade

dantepruden174
Jun 1
2 min read

A Sharp Blade Is the Difference Between “Meh” and “Manicured”

If your grass is looking yellow or ragged after mowing, it’s probably not your watering or fertilizer — it’s your blade. Dull blades tear the grass instead of slicing it clean, which stresses the lawn and opens the door to disease.

Here’s how to tell when it’s time to sharpen, how to do it, and when to just replace the blade altogether.

Why It Matters

Clean cuts heal faster
Healthier lawn with greener color
Prevents brown tips and fraying
Mower runs more efficiently and doesn’t overwork the engine

Signs Your Blade Is Dull

Grass has yellow or brown tips after mowing
Mower leaves uneven patches or doesn’t cut on the first pass
You can physically see nicks or dents in the blade
You’re mowing slower than usual to get a clean cut

If you’ve mowed 10+ times since your last sharpening, it’s time.

How Often Should You Sharpen?

Homeowners: Once or twice per season
Heavy users (weekly mowing or multiple properties): Every 20–25 hours of use
After hitting a rock or hard object: Immediately inspect or replace

How to Sharpen Your Mower Blade

What you’ll need:

Wrench or socket set
Metal file, bench grinder, or blade sharpener
Vice or clamp
Gloves and safety glasses

Steps:

Disconnect the spark plug (for safety)
Remove the blade (note which side faces down)
Clamp it in place
Sharpen at the existing angle, using even strokes
Check balance (hang it on a nail — if it tips, file the heavier side)
Reattach and tighten

Tip: If the edge is rounded or bent, sharpening won’t fix it. Time for a new blade.

When to Replace Instead of Sharpen

Blade is cracked or bent
Cutting edge is less than 1/4" thick
Sharpening doesn’t improve your cut
You’ve already sharpened it 3–5 times and it’s worn down

Bonus Tip: Keep a Spare Blade

Having a second blade on hand means no downtime if one gets damaged or needs sharpening. Swap it, sharpen later.

Want the Pros to Handle It?

At Acres Lawncare, we keep our blades razor-sharp, so your lawn gets clean cuts every time. We don’t guess — we sharpen on schedule, inspect regularly, and replace when needed.