How often do you have to replace the blades of a robotic lawnmower?

Sharp blades are essential for producing a clean cut. As parts wear down, replacing the blades is therefore inevitable, even with good care. However, since there are always costs involved, blade replacement should not take place more frequently than necessary. So, what is the ideal interval when replacing the blades of your robotic lawnmower?

The service life of the blades of a robotic lawnmower depends on several factors, at least some of which you can influence positively. Nevertheless, even with very good care, the blades will dull sooner or later. To ensure that the cutting pattern remains clean, regular replacement of the blades is unavoidable. But how often is this necessary?

Reasons for changing the blades of a robotic lawnmower

Blunt blades have a negative effect in several respects. 

  • The cutting pattern becomes unclean if the blades only hack off the grass instead of cutting it cleanly. This can result in an increase of brown tips giving your lawn an unhealthy look.
  • The noise level  increases with dull blades. Even robotic mowers, which are actually whisper-quiet with less than 60 dB during operation, become louder as a result and eventually disturb the idyll in the garden.
  • Blunt blades lead to increased power consumption. In this case, the robot has to dock the charging station more frequently. This, of course, will affect mowing times as well as the overall battery life.

Factors affecting blade life

The life of the blades of a robotic lawnmower varies significantly. Some factors you can influence, others less so. For example, collecting foreign objects such as fallen fruit, cones or branches and shorter mowing times can significantly extend the service life.

  • First of all, the most important point is the frequency of use of the robotic lawnmower. The more often the device works, the faster the blades will wear down.
  • Objects on the lawn that get into the blades will cause them to dull more quickly.
  • The type of lawn also affects the life of the blades. More robust lawns result in slightly faster wear of the blades.
  • The condition of the soil affects the rate of growth and, indirectly, the durability of the blades. On sandy soil, for example, the lawn usually does not grow as fast so the blades stay sharper longer.
  • Similar to the soil conditions, the seasons and weather conditions also influence the service life of the blades. In the spring, rapid growth causes the blades to wear down more than in a dry summer. 
  • Material and quality the blades: the high-quality blades produced by our manufacturers usually last longer than cheap imitations. It is not uncommon for cheap blades to also pose a safety risk when pieces break off and are left unnoticed on the lawn.

Blade plate or star blade

Finally, the type of blade also affects it’s durability. Blade plates - usually three – have significantly thinner blades that are less able to cope with foreign objects than robust blade plates. The interval for replacing the blades is correspondingly more frequent so that the cutting pattern remains nice and clean in the long run. This is usually around 1-3 months for knife plates, while star plates sometimes only need replacing once a season. Keep in mind that star plates are also somewhat more expensive to purchase.

Ultimately, it is advisable to understand the manufacturer's specifications as a guideline and to determine the time for blade replacement based on the cutting pattern of the lawn. Frayed tips are easy to spot and a clear indication of dull blades.

Follow manufacturer's instructions

It is not possible to make a blanket statement about how often the blades on the robotic lawnmower need to be replaced, and it also depends on your model. While some manufacturers recommend a monthly change, which can be delayed somewhat by particularly long-lasting blades, it is sufficient to replace the blades in other devices once or twice per season.

Changing the blades on the robotic lawnmower yourself

Replacement blades are available for each model from the manufacturer and from specialist dealers. Changing them takes only a few minutes and usually requires no more than a screwdriver. The change is even easier with a special click system and the required tool is included in the delivery.

For safety reasons, it is advisable to wear safety gloves when handling the blades. They are similar in sharpness to razors and cause cuts even with a little carelessness.

Even without considering the interval for changing the blades, it is recommended to check them frequently for wear and tear. A good time is certainly when cleaning the mowing deck, which is done regularly anyway.

The manufacturer's specification for replacing the blades is only a guideline. The durability of the blades depends on several factors and it is not possible to make a blanket statement about the correct frequency of blade replacement. It is best to observe the cutting pattern and regularly check the blades for wear in order to determine the ideal time for blade replacement.