How often should you replace lawn mower blades?

How often should you replace lawn mower blades

Over time blades dull, it doesn’t matter if you have a knife, gardening shears, or robotic lawn mower blades. So, it’s important to change them periodically. But how often should you replace lawn mower blades on your robomower?


Ideally, you should change your robomower’s blades every 1 to 3 months. While this is a wide time range, it does depend on the model, the condition and size of your lawn, and the type of blades you use.


One thing is certain, it’s important to change the blades regularly to ensure a healthy lawn, peak robomower performances, and the best cutting pattern.


Let’s explore how often should you replace lawn mower blades on your robot mower?



Why change the blades on your robomower?

Over time, your robot lawn mower’s blades will wear out. You’ll notice the grass isn’t being properly cut and looks uneven. Apart from the cosmetic problem, you could find your lawn is damaged and in poor health. The cost of solving these issues could be huge.


The blade’s condition affects multiple things, including the cutting pattern, the speed at which your robotic mower operates, and how precise the cut is. Another thing you’ll realise with blunt blades is that they add to the mowing noises. 


Using new, high-quality blades reduces the overall noise your robot creates, but also ensures your machine uses less energy and completes the job faster. If you’re using less energy, your battery will last longer, and your robomower will spend less time charging.


Plus a set of new, high-quality blades costs around £20, which is a small price to pay, especially compared to spending hundreds of pounds on a new battery.



How long do robotic mower blades typically last?

Predicting how long blades will last is very difficult. To slightly confuse things, the majority of manufacturers suggest changing the blades every 1 to 3 months. Using this rule of thumb, you might change blades 5 times during the summer or twice, depending on a range of factors.


With the large, star-shaped individual cutting blades, you should only need to change them once a season. Other types of blades will require more frequent attention. Again, the cost of new blades is minimal, especially compared to purchasing the unit or a new battery.



robotic mower blades lifespan



What elements affect the blade’s life?

There are plenty of factors involved that can shorten the life of your blades. These include soil, grass type, lawn size, and garden objects (branches, fallen fruit, pine cones, rocks, etc.). All of the natural elements have an impact on your robomower’s blades.


But we also have to consider the quality of the blades themselves. You can’t expect poor-quality blades to last a long time or stay sharp for more than a couple of mows. So, it’s worth investing in high-quality blades and monitoring the results.



How to tell if your blades are blunt?

It can be hard to tell if your robot mower’s blades are blunt. And unless you enjoy keeping notes of when you last changed them, it can be a bit of a guessing game. Thankfully, there are a few clues we can look for.


If the tips of the blades of grass are no longer cleanly cut but frayed and greyish-white or even brown spots form on the top, it’s time to replace the blades.


If you turn over your robot and see wear on the blades, which could result from them hitting branches, rocks, or pine cones, it’s time to change them.



Does lawn size influence blades’ life span?

You don’t need to be a rocket scientist to realist the larger the area of lawn, the more wear you’ll add to the blades as it has more grass to cut. However, this is only part of the problem.


We also must consider the soil and grass type. You’ll need to cut fast-growing grass more often. If your lawn uses a more hardy type of grass, it’ll require more power to cut it. Both of these situations increase the wear on your blades.


Grass grows differently, depending on the season. So, your blades will wear at different rates throughout the cutting season. In spring and summer, you’ll notice grass grows quicker than in autumn. You’ll see virtually no growth in winter and should store your robomower inside.


Many other things can also damage your blades, including stones, gardening tools, and dog/kids toys. And while it might be impossible to remove all of these, it’s worth being aware of the long-term impact they can have.


Some high-end robotic mowers have built-in weather timers that calculate how quickly a lawn is growing. They will adjust their mowing schedule accordingly. As a consequence, the blades also wear out more slowly or faster, depending on the mowing frequency.



robot mower blades durability



Can you increase the durability of the blades?

It’s not all doom and gloom. There are a few steps we can take to improve the blades’ durability. Thankfully, these are easy to manage and have a big impact on the life of your robomower’s blades.


Removing objects from the lawn

It’s vital to ensure no foreign bodies get into the mower deck. So, you want to remove stones, garden tools, toys, twigs, tennis balls, branches, and anything that could dull the blades and shorten their lifespan.


Also, you should clear any piles of leaves from your lawn before your robot mower gets to work. Not only can leaves cause the blades to dull more quickly, but can also cause the robotic mower to use more energy while mowing. 


Try to shorten the mowing time

As already stated, the longer the mower is working, the more the blades will be used, reducing their life. There are a few things you can do to avoid unnecessary mowing. 


Firstly, take into account the season and weather conditions. If your robomower is highly active in autumn, there’s something wrong as it should be mowing less. So, it’s worth tweaking the setting by season to respond to the changing demands.


If you expect heavy rain for a few days, it could be worth bringing your robomower inside, so it doesn’t try to mow in bad weather conditions. Instead, wait until the weather improves and let it run as normal.


Next, try to shorten the operating window. Your mower shouldn’t be working 16 hours a day, 7 days a week. In most cases, you can get a lush lawn with an hour or two of mowing every few days. So, adjust the setting so it works in the middle of the day for a short time.


Some of the more affordable units use quite simplistic navigation, which can actually wear blades out quicker and shorten the battery’s life. A robomower with more advanced navigation will map your lawn and optimise the cutting pattern can save your blades and battery.


Some units use GPS-supported navigation to create a digital map of your garden that is used to optimise the mowing routes and avoid unnecessary overlapping mowing. However, expect to pay more for GPS-supported navigation.



Is changing the blades easy?

As with a traditional lawn mower, changing the blades on your robot mower is usually pretty painless. You might be able to remove the blades without any tools and replace the old ones with new ones. 


However, most robomower will require you to use a screwdriver or Allen key to remove the blades or cutting disc before you can replace them. If you’re unsure, either read the manual that came with your unit or contact the manufacturer.


After changing blades once or twice, you’ll get the hang of it. We recommend using titanium-coated blades as they typically last longer and are highly affordable.



robomower blades sharpening



Can the blades be sharpened?

You can sharpen the blades of your robotic mower, allowing you to continue using them. However, this might not be your best option.


If you have no experience in blade sharpening, we don’t recommend trying as there is a specific skill involved. Plus, buying a grinding tool can be expensive. If you’re willing to learn, invest in a very good Japanese sanding tool as it will help you produce an acceptable result.


You could use a local gardening centre as they should have the expertise, but the cost might be close to buying replacement blades. Not to mention the time you’ll spend.



So, how often should you replace lawn mower blades?

It’s worth replacing your robomower’s blades every few months. Doing so, will improve the cutting pattern and keep your lawn healthier. Don’t be lazy and leave them for a long time as you could create bigger problems down the line.


How often should you replace lawn mower blades? It depends. If your mower is working daily, the blades will wear out quicker than if it’s being used for an hour every few days. Your lawn’s size and grass type will also impact how often you’ll need to replace your robot mower’s blades.


If in doubt, read the manual, ask the manufacturer and test different blades. With some experimentation, you’ll soon have a better idea of the best blades to use and the ideal frequency at which to change them.