What does a robotic lawnmower do with leaves

Leaves can affect the health of the lawn and, therefore, should be removed regularly. With a classic lawn mower, you can just drive over them, shred them and collect them in a grass catcher. But what does a robotic lawnmower do with leaves?

When trees shed their leaves in the fall, another labor-intensive phase begins. After all,  fallen leaves should not be left on a lawn for too long. Otherwise, there is a risk of mold and rot. With a classic lawn mower, this work can be done quickly since the leaves are shredded in the mower deck, transported to the bagger (along with the lawn clippings) and can be easily disposed of. But what about a robotic lawn mower? These devices are designed to mow a lawn that is free of barriers and obstacles. Especially in the fall, however, it‘s often the case that fallen fruit or leaves are lying around and make the robot's work more difficult. What exactly happens when the robotic lawnmower encounters autumn leaves?

Problems with autumn leaves and robotic lawnmowers

First of all, every garden owner should attempt to remove large amounts of leaves from their lawn in a timely manner. Otherwise, the necessary aeration of the lawn is quickly reduced, and there is a risk of mold and rot especially in cold, wet weather. Fungal diseases also spread more easily under the layer of leaves.

Your robotic lawnmower will have an easier time doing its job if you regularly rake up fallen leaves. When damp, leaves can become slippery, causing the robotic lawnmower to lose its optimal grip on the ground. If damp leaves stick to the wheels, this effect is further intensified. The wheels can start to spin and the robot could get stuck, especially on slopes. This rotational movement in turn promotes wear of the turf.

Another problem can arise when a thick layer of leaves prevents accurate lawn trimming. If the blades cannot properly cut the lawn due to a large amount leaf coverage, the cutting pattern may suffer. This is particularly evident when foliage collects in depressions or uneven ground, thus preventing the robot from grasping the underlying lawn.

Does the foliage damage the robotic lawnmower?

In principle, the blades of the robotic lawnmower simply shred autumn leaves. With that being said, this is usually accompanied by faster wear of the blades, which is much greater on blade discs than on robust star blades. Of course, the wear of the robotic lawnmower depends on the amount of leaves. Further damage to the robotic lawnmower itself is generally rare and  can occur when very compact devices encounter extremely large quantities of leaves, resulting in a blockage of the blades.

In the case of medium amounts of leaves, it is mainly the blades that may be affected. If leaves get stuck on the wheels, traction deteriorates, which promotes slipping, especially in wet conditions. Conversely, the wheels spin more easily on slopes, which can cause unnecessary damage to the turf.

The robotic lawnmower increasingly struggles with larger amounts of leaves. This greater load can cause the motor to wear out quicker. In addition, the ejected leaves can damage the lawn and there is a risk that the robotic lawnmower could injure small garden critters hiding under the leaves.

Mulching leaves with the robotic lawnmower?

With classic lawn mowers, it is possible to collect autumn leaves in an uncomplicated way. To do this, mow the lawn as usual. The leaves are shredded by the mower together with the clippings and thrown into the bagger in a compressed form. From there, you can simply dispose of it in the compost or an organic waste bin. But what about robotic mowers that work on the mulching principle and do not have a grass catcher?

Star blades are generally robust enough to shred leaves just as easily as lawns. Nevertheless, wet leaves in particular tend to stay put and are only cut by the device. Also bear in mind that robotic mowers were not designed as leaf shredders and may wear out considerably quicker mowing  large quantities of leaves.

What’s more, shredded leaves may also promote the formation of moss on the lawn. Tannic acid from oak or walnut leaves can have a negative effect on soil quality.

Finally, the cutting pattern also suffers under the layer of leaves. If the robotic lawnmower is struggling with large quantities of leaves, the blades of the lawnmower may no reach every blade of grass and the cutting pattern is no longer accurately uniform.

Unlike fine lawn mulch, leaves do not decompose en masse within a short period of time. If they have already been shredded by your robotic lawnmower, this makes raking them up even more difficult. Clearly, it makes more sense to collect leaves before the robotic lawnmower starts its work. Battery-powered leaf blowers or the classic rake are suitable for this purpose.

Which robotic lawnmower is suitable for leaves?

Hardly any garden owner will have the time or patience to remove leaves every day, so there will always be the odd leaf on the lawn when the robotic lawnmower starts. In this case, if you have several trees in your garden, it is best to choose a model that copes with leaves particularly well. Helpful features here are:

  • All-terrain wheels with a thick profile that have a good grip even on wet leaves. This helps to reduce the risk of the robotic lawnmower getting stuck on slopes. Traction can also be optimized with a wheel brush, designed to  remove damp leaves from the wheels directly during operation.
  • A pendulum-mounted mowing deck designed to  compensate for uneven ground and  provide an even cut even with some leaves on the ground.
  • A robotic mower fitted with a robust star blade. If there is too much foliage, this too may wear out faster than usual but initially tends to cope better with amounts of foliage than the blade discs.
  • A mulch remover helps  prevent leaves from collecting on the underside of the carriage and impair mowing performance.
  • Wheel brushes help remove leaves and other debris directly while the machine is in motion to maintain optimum traction.

Robotic mowers and autumn leaves: lawn care tips

  • Make sure the lawn is largely free of leaves. Random leaves do not harm the robotic lawnmower, nor do they generally affect the cutting result. The situation is different, however, if there is a closed layer of leaves on the lawn.
  • Avoid operating the robotic lawnmower if there is a lot of wet leaves in the garden. Despite off-road models, there is  a risk that the wheels will damage the lawn. It is also easy or damp leaves to stick to the wheels and the lawnmower blades may become blunt.
  • Always check whether there are objects under the layer of leaves that can harm or be harmed by the robotic lawnmower. Stones in particular can cause serious damage to the blades. Conversely, hedgehogs or other animals could be hiding under the leaves.
  • Autumn is an ideal time to rid the lawn of moss and weeds once again. This works best with a scarifier, which carefully pulls the lawn thatch out of the lawn. For best results, set the cutting height of the robotic lawnmower to about 2-3 cm.

Robotic mower without boundary wire for autumn leaves

Most robotic mowers navigate using a boundary wire that is placed around the lawn prior to initial operation. The device then uses an electrical signal to detect which boundary is not to be crossed.

The situation is different for robotic lawnmowers that do not require a boundary wire. These work with grass sensors that "scan" the ground and mow everything that looks like grass. If there are leaves on the lawn in autumn, the distinction is noticeably more difficult. The robotic lawnmower may no longer be able to recognize which areas are lawn. Particularly, if there is a closed cover of leaves from the lawn to the beds, the robotic lawnmower may cut ground cover or shrubbery in the beds.

For robotic lawnmowers without a boundary wire, it is extremely important to remove leaves before mowing in order to clearly mark the lawn edges.

Garden tools for removing leaves

In order to protect the robotic lawnmower, it makes the most sense to remove leaves regularly before mowing. This is certainly not always possible during heavy falls in autumn, but is certainly recommended to do so now and then to increase the longevity of the blades and other lawnmower parts. Even if the wear and tear of the blades does not represent a technical defect, replacing parts more often will have an effect on your wallet. Several tools are available for removing leaves:

  • Removing leaves, branches and other foreign objects with a classic rake may be ideal for the job, especially in small gardens.
  • Leaf blowers are efficient for removing leaves from larger areas. They come in electric, cordless or gasoline models, and some are equipped with a collection bagger (i.e., leaf vacuums) designed to directly shred the leaves and compress them for disposal.
  • The classic lawn mower  may no longer be needed if there is a robotic mower. However, for collecting leaves and lawn clippings, a model with a grass catcher is a good choice.
  • On very large areas, a great option is to use lawn tractors with trailed leaf sweepers.


Smaller amounts of leaves are generally not a problem for either the lawn or the robotic lawnmower. In this case, it is advisable to choose a robotic lawnmower with a star blade that can carefully shred leaves. The blades may wear out slightly faster, but other signs of wear on the mower are usually rare. In addition, it is advisable to purchase a device with a mulch remover and traction wheels, which help  give the robot the necessary grip. However, when large amounts of leaves accumulate on your lawn, it is time to remove them with a rake or battery-powered leaf blower before your robotic lawnmower makes its rounds.