How To Sharpen Hedge Trimmers

How To Sharpen Hedge Trimmers

If you use your hedge trimmer effectively, sooner or later, it will become blunt. Like every mechanical cutting tool, you need to sharpen your hedge trimmer to keep them as sharp as possible.

For every cut a trimmer makes, it technically gets duller. Experts believe that a trimmer is due for sharpening after every 50 hours of use.

It is a frustrating experience trying to trim with blunt tools. The branches would keep getting trapped and jammed in the trimmer, and what used to be very neat cuts would start becoming uneven and disjointed.

Once you start seeing these signs, you immediately know that you need to sharpen them. Whether it’s a powered trimmer or a manual one, you need to sharpen them, or they will soon stop delivering altogether.

Getting your tools sharpened is not complicated, and it would save you a lot of time that would be spent getting your hedges in shape.

Sharpening your tool is a routine maintenance procedure. If you have a gas-powered hedge trimmer, you’ll need to maintain more than the blades.

For this article, however, we’re looking at how to sharpen the blades. The procedures we will look at can be done at home. However, you can always contact a professional if you need expert advice on getting your blunt hedge trimmer working perfectly again.

Why is hedge trimmer sharpening important?

Why is hedge trimmer sharpening important?

A hedge trimmer is supposed to trim hedges. Sometimes the job becomes a bore because the blades become blunt. Naturally, after prolonged use, edges become blunt, which is not unusual. However, there is an easy solution. Sharpening!

By sharpening, we mean getting the trimmer’s blades back to their original functionality. 

Sharpening hedges is essential because that is the only way of getting the trimmer to keep working well continuously.

A dull hedge trimmer will make the job more tedious, but it is also dangerous and may eventually damage the trimmer as twigs and branches keep getting stuck in the trimmer.

Once you notice that you no longer enjoy trimming your hedges, a simple sharpening procedure may be all you need.

Hedge Trimmer Sharpening Safety

Hedge Trimmer Sharpening Safety

Once you discover that you need to sharpen your trimmer, you need to get the tools ready. But before then, safety first!

As with every tool, you need to operate them safely. Sharpening your hedge requires some recommendations. Most of them are not different from the safety precautions you adhere to when trimming.

The most crucial step is to always protect your eyes before starting. Always wear safety goggles that are ideal for such procedures. Of course, you shouldn’t wear ordinary glasses.

Again, you should always wear safety gloves as you’ll be working with sharp blades. The gloves should be made from rigid materials that can withstand pressure.

Your clothing shouldn’t be too loose, and you should wear footwear that adequately protects your feet from slipping.

As part of the precautions, you should work only from a flat surface. If you have a large enough table to be used, be sure that it is well-balanced. This is to prevent the blades from falling and causing injuries.

Also, no matter how it is powered, ensure that your hedge trimmer cannot start suddenly while working on it. That means you should disengage it if it is corded, or the battery should be removed if it is a cordless trimmer.

It could be really dangerous if the hedge trimmer suddenly roars to life start while you are working on it.

Hedge Trimmer Sharpening Timer Guide

Hedge Trimmer Sharpening Timer Guide

The frequency of sharpening your hedge trimmer depends on how often you use them. Typically, it is expected that your trimmer is due for sharpening after every 50 hours of use.

But whenever you discover that the hedge trimmer is no longer as effective as it should be, you may need to sharpen it.

Most hedge trimmers come with a manual explaining how often you should sharpen them. Do well to consult it before proceeding. You may also refer to a professional for more advice.

Tools and equipment

Tools and equipment

Sharpening your hedge trimmer can be conveniently done at home. To do so, you’ll need these tools:

  • Flat file
  • Safety glasses
  • Soft cloth
  • Water
  • Solvent
  • Whetstone
  • Work gloves
  • Safety clothing

Step-by-step guide

Step-by-step guide

Now let’s go through a step-by-step procedure to get the trimmer sharpened.

Clean the teeth

The first step in sharpening your hedge trimmer begins with cleaning its teeth. The teeth of the hedge trimmer would have residue of resin, plant sap, and other substances.

Before proceeding, it is essential to get these residues out of the way. This is done by using a soft cloth. Wipe off the dirt until the blade is clean. Remember, this dirt is partly responsible for the dullness of the teeth.

Sharpen your hedge trimmer blades with a flat-file

You should wear your gloves while working on your hedge trimmer. Once the blades are clean, you should proceed to the main business. You’ll need a flat file.

Start your sharpening by filing the edges of the blade. The file works in only one direction, and that is forward. It has to be towards the edge because that’s where sharpness can be achieved.

Also, make sure that you maintain the proper sharpening angle. Sometimes, the manual can explain the appropriate angle for your file.

When filing, you aim to achieve sharpness. However, you may think thinning off the edges until parts of the material chip off would make it sharper. That would be counterproductive. Always file in moderation.

If you reduce the blade’s surface area through filing, it becomes weaker, and the lifespan is reduced. Always ensure that while filing, the standard limit for abrasion, which is set at 5mm, is always maintained. If not, it reduces the ability to cut through branches as effectively as possible.

When filing your blade, always resist the urge to operate it in a back-and-forth motion. You should only file in one direction, and that is forward. If you go back and forth, you’ll neutralize the file’s sharpening effect on the blade.

Every backward stroke of the file blunts rather than sharpens it. So, always try to maintain forward motion only.

There are two sides to each blade, so ensure that you sharpen both sides evenly. One side shouldn’t be filed more than the other.

Finally, limit your filing to the edge only.

 Deburring with a whetstone

While you are sharpening the blade, burrs would develop on the underside of the blades. You need to remove them, or they may cause the trimmers to be less effective.

Turn the hedge trimmer upside down so that you can work on the blade’s undersides. Use the whetstone to smooth off any burrs that have developed in the bottom of the edges by drawing it along the blade, wiping off the burrs.

As you do this, you smoothen the surface and make it clean. Remember, your gloves have to be in your hand throughout this procedure.

Finishing Touches

For this, you need the STIHL solvent. Simply spray it on the parts you have worked on as a finishing touch.

Once you’re done, clear the workshop area and inspect your trimmer. It should be as sharp as new. Remember, this procedure is straightforward and can be done at home.


After constant use of hedge trimmers, they are sure to get blunt. When they do, how do you make them sharp again?

We’ve learned how to sharpen hedge trimmers without any supervision. It is a straightforward process and requires only a few tools. However, we recommend that you visit a professional if you have doubts about doing this yourself.

Remember, safety first!

If you must sharpen your hedge trimmer yourself, you must always have your personal protective equipment, especially the safety goggles and safety gloves. With these, you should be able to make your trimmers sharp as often as necessary.


About The Author

Gina Harper grew up dreaming about farms and growing her own food. She began an urban garden to feed herself and turned it into an incredible hobby. Gina is here to teach you everything from raised beds to container gardening, how to keep plants alive and well in a smoggy city, and the works. It’s time that we carve our own piece of green earth and reap what we sow—she’s here to help you with that.