One of the leading suggestions by service providers to maintain grass health is to sharpen your blades regularly. As a property maintenance service, we sharpen our blades every week or two. This can be quite a lot of work but it is an important part of equipment servicing to ensure the overall health of your grass.
The reasons sharp blades are so important is because they slice the grass much more cleanly. Imagine the slicing of a blade of grass like a cut to your own skin. Have you noticed that a clean incision like a paper cut or a knife cut heals much quicker and stronger than a jagged one like from falling in gravel or gouging yourself on a jagged piece of metal? The same biological healing properties apply to grass. The wound can close much quicker in a clean slice than a thick or jagged wound because there is much less surface area to close up. The same surface area principle applies to grass. The edge of the grass that was sliced has less surface area to seal off when it was seared cleanly, than when it is whacked in a jagged manner with dull blades. Further, the less surface area that is exposed the tougher it is for disease to creep in.
This creates less stress for the plant to heal and grow. Another human body analogy related to plant stress is our own ability to fight off a cold or infection when our immune system is fully charged vs when we are weak. When we haven’t slept or are experiencing stress, this is when we get sick. The more stress a plant experiences, the less strength it has to fight off disease. For these reasons it’s important to trim the grass in the cleanest manner possible.
This means constant blade sharpening. For a homeowner that means once every month or so depending on how often you are mowing your grass. A good way to tell is the same way you measure the sharpness of a hockey skate by dragging your finger nail gently along its edge and see if the blade is sharp enough to peel of a light layer of your finger nail. Try not to touch the blade with your skin unless you are very experienced as you can cut yourself quite easily. If the blade does not file off your finger nail it should be touched up and sharpened.
The blade needs to be removed from the mower by removing the bolt that attaches it to the engine shaft. Typically you will need to secure the blade in place before loosening this bolt as it can be tight. Usually you will have to hold the blade so wrap some thick material like a towel around the blade so you can hold it tightly without gashing yourself open. Secure the blade and you should now be able to loosen the bolt.
The first and obvious way to sharpen the blade is to take it to your local small engine mechanic but this could leave you waiting for a while and will cost you money. Since you have already demonstrated the mechanical ability to get the blade off, let’s teach you how to sharpen it yourself.
You’ll need a vice grip to fasten the blade in place. Once it’s secured in place bring out the grinder and grind only the previously ground upper face of the blade. Do not grind the lower side of the blade. A slight over grind will occur which you can remove with a hand file to get that extra sharp condition from your grinding. Repeat this step for the other side of the blade and for any spare blades you have built up. It’s best to get multiple blades so you can sharpen 2, 3 or even 8 blades at once so your sharpening frequency is reduced. This way all you have to do is swap out blades. We have close to 15 sets of blades for some of our mowers so we can sharpen them all at the start of the season and simply swap the dull blades out with a fresh set of sharp ones. This might be a bit excessive for you as a homeowner but it gives you an idea.
To put the blades back on your mower simply reverse the steps you completed to take them off. Now you have sharp blades so you can mow your grass in the healthiest way possible and ensure the most lawn health possible.