Almost all lawnmowers have problems with edges and borders. However, with robotic mowers these are somewhat more pronounced than with normal lawnmowers, which is often seen as a negative point. So you are right to ask whether there are robotic mowers that can mow right up to the edge and which models these are. Here I would like to give you a rough overview.
Which robotic mowers can mow right to the edge of the lawn? Due to the distance between the mowing unit and the body, no robotic mower can mow right up to the edge. However, some models do get very close to the edge, so that only a few centimeters remain. These robotic mowers have a special edge mode with which they mow the edge. They include robotic mowers from the following manufacturers:
Why is mowing the edge such a problem? Which models are there that mow to the edge and are there differences? You will find out in the next sections.
In the following, the “edge mode” is often mentioned, but sometimes also the “edge mowing function” or “mowing close to the edge”. This is always more or less the same. The manufacturers sometimes call their systems differently and even with their own models, the names do not always remain consistent.
By the way, here you can find a current overview of all current robotic mowers with edge mowing mode, which I would recommend.
Which Robotic Mowers Mow Closest to the Edge?
Just as with normal lawnmowers, there is practically no robotic mower that can mow completely to the edge without other measures being taken. This is due to the fact that there is a certain distance between the mowing unit and the body of the mower due to its construction. In order for the robotic mower to mow completely to the edge, the blades would have to protrude from under the bodywork.
A robot with such a construction might not be sold at all for safety reasons. In any case, some robotic mowers, especially those that have a blade disc instead of a cross or star blade, are equipped with an additional safety distance between the mowing unit and the body, so that this distance is even greater than with other robotic mowers or lawnmowers.
But even the random driving style does not allow most robotic mowers to mow the edge correctly by “chance”. They often hit the edge at an angle instead of driving parallel to the edge. If they hit the edge from the front, for example, the distance between the mowing unit and the car body is even greater.
For this reason, the manufacturers of some robotic mowers came up with the idea of developing a special edge mode, with which the robotic mower drives over the edge once completely at regular intervals and mows it. This can be done especially by models of the manufacturers ROBOMOW and WORX..
These are some well known models of these brands:
- ROBOMOW RC306
- ROBOMOW RS612
- ROBOMOW RS622
- ROBOMOW RS630
- ROBOMOW RX20
- WORX Landroid L 20V WR150
- WORX Landroid L 20V WR153
- WORX Landroid M 20V WR140
- WORX Landroid M 20V WR143
Of course there are many more models from these manufacturers, which I cannot go into detail here. The main focus here is on the edge mowing function. Often there is a similar version of a model for larger or smaller gardens.
The Edge Mode of ROBOMOW
ROBOMOW relies on robust star blades for its robotic mowers, unlike e.g. WORX or HUSQVARNA. These are quite large and reach very close to the edge of the body. This has the advantage that ROBOMOW robotic mowers come closer to the edge, but at the same time this is associated with a slightly higher risk of injury.
However, this does not mean that ROBOMOW ignores the safety problem. As the rotating blade is located in a kind of movable tub, which adapts to the ground, sufficient safety is still guaranteed. A star blade can, nevertheless, occasionally cause an accident, and cause worse injuries than a knife plate. On the other hand, it can cope better with leaves, fallen fruit and branches.
The special thing about ROBOMOW robotic mowers is not only that the blades reach closer to the edge of the mower, but that the edge mode is part of the software. You can program this in such a way that it is carried out on certain days, or even every day, before its regular mowing. The robotic mower will then drive along the outside of the boundary wire and mow the entire edge.
A small strip of lawn of approx. 6 cm will remain along the wall. With other lawn borders, the robotic mower can mow the entire edge, depending on the nature of this border. See also robotic mower boundary wire: The correct distance from the edge.
The two best known ROBOMOW models are the ROBOMOW RC306 and the ROBOMOW RS612. These two models differ mainly in their area output, size and weight.
While the ROBOMOW RC306 has a maximum area capacity of 0.38 acre, the ROBOMOW RS612 manages a maximum of 0.75 acre. These maximum values are however purely hypothetical. Only recently I wrote an article about how you really must interpret the maximum output statistic.
In addition, the cutting width of the ROBOMOW RS612 is 22 inches, twice as large as that of the ROBOMOW RC306, which of course also influences the area output. With 44.5 lb, the ROBOMOW RS62 is also almost twice as heavy and is therefore one of the heaviest robotic mowers on the market.
I would recommend ROBOMOW especially for medium to large yards, where no lawn edge stones are laid. If the yard has a lot of leaves or fallen fruit, they are more suitable than other robotic mowers with edge mode. The rain sensor can also be an advantage. Whether you need a rain sensor or not, you can figure out here. Be careful, however: if you have children or pets, it is best to adjust the mowing times accordingly. If you want to take a closer look at the two robotic mowers, you can find them here on Amazon.
The Edge Mowing Function of WORX
The mowing unit of WORX robotic mowers is clearly built differently than that of ROBOMOW. WORX robotic mowers do not have a star blade, but a blade disc with freely swinging blades. Three of these are attached to one blade disc. Due to the rotation of the disc, they are pressed outwards during mowing. The risk of injury is somewhat smaller with such a mowing unit.
Many robotic mowers with blade discs also have a fairly large safety distance between the mowing unit and the bodywork. But this is not the case with WORX. Here the whole thing is solved a bit differently. The mowing unit is not located centrally under the robot, but is offset to the right when you look at the robot from the back.
On this side, the mowing unit comes very close to the outer edge of the robotic mower. However, in order to ensure safety, if the robotic mower should run over someone’s foot, there is a kind of shield on this side through which only the grass penetrates, but not a foot or other object that gets under the robotic mower.
WORX robotic mowers also have an edge mode, which they call “Cut-to-Edge”. The principle is the same as with ROBOMOW. The robotic mower drives at regular intervals along the outside of the boundary wire, counterclockwise. This way the offset mower is on the outside where the grass is to be cut and the robotic mower gets very close to the edge.
Along solid obstacles, such as walls, a thin strip of grass of about 6 cm will remain. Along flower beds or ground level boundaries, the robotic mower can even mow completely to the edge, if it can drive a small distance beyond the edge of the lawn. Here it depends on how you lay the boundary wire. You can learn more about this here.
Two very popular models from WORX are the WORX Landroid M 20V WR140 and the WORX Landroid L 20V WR150, these two models mainly differ in their area output. The WR140 has a maximum area output of ¼ acre, while the WR150 can cover ½ acre.
Besides their differences in maximum area output, many of their functions are the same or very similar. They have the edge mowing function, which is the subject of this article, and both also have a rain sensor, can be controlled via app, and use the patented AIA technology from WORX for better navigation, as well as having a multi-zone program.
The devices are somewhat cheaper than the devices from ROBOMOW, but at the same time they are also intended for somewhat smaller areas. In general WORX robotic mowers belong to the middle class segment and have quite a good price-to-performance ratio.
I would recommend WORX robotic mowers for small to medium sized lawns that do not have too much fallen fruit, leaves, or fallen branches during wind or storms. Due to the mowing mechanism, they are somewhat more suitable for households with children and pets, as the blades cannot cause as much bodily injury and material damage as a star blade. WORX robotic mowers are comparatively inexpensive and of good quality. You can often find good bargains here, especially if you pay attention to the promotions of various hardware stores that sell the devices. They are also available on Amazon if you want to take a look at them.
The WORX Landroid M 20V WR140 is currently being replaced by a newer model and can therefore no longer be found on the manufacturer’s website. But it will still be available in stores for quite some time, at very favorable prices.
Other Robotic Mowers with Edge Mowing Function
There are other robotic mowers with edge mowing function, but they are not sold in the USA at the moment. These include some models from YARD FORCE, AL-KO, and the AI-controlled TOADI, which is still in the beta phase.
Also the Terra from iRobot will probably have some kind of edge mode. However, one employee told me that due to Covid-19 the launch of the product has been postponed indefinitely and during this time things may change on the product, so it is not 100% clear what features the product will have.
Where Are the Limits of the Edge Mowing Mode?
The edge mode of the devices presented here has its advantages. The robotic mower comes closer to the edge, which eliminates the annoying re-trimming typically needed in some areas. Along solid obstacles such as walls or fences, however, you still have to trim because the robotic mower, no matter which model, will not mow right to the edge.
This can be remedied by the use of lawn edging stones. Together with an edge mode, you can lay pretty narrow lawn edging stones. But also think about the future: if you ever want to change to another robotic mower that doesn’t have an edge mode, you may need wider lawn edging stones. If you are interested in this topic, take a look at my article on lawn edging for robotic mowers.
The edge mode only works properly if the edge is always free of any obstacles, otherwise problems may occur. It is therefore important that the edge is always free and that there are no flower pots or the like ever sitting here.
As the robotic mowers presented here all use the boundary wire for navigation, for example to find their way back to the charging station, it is absolutely necessary that the boundary area is never blocked. Robotic mowers with a guide wire such as MCCULLOCH or HUSQVARNA do not have this problem.
A further limitation of the edge mowing mode is that it cannot be used to mow the edges of islands, as the robotic mower cannot find the islands via the boundary wire. The boundary cable that leads to and from the island is virtually non-existent for the robotic mower, as the magnetic field of the cable is deliberately cancelled out here. Therefore it can not drive over the cable to the island.
The problem can be somewhat avoided by creating “pseudo islands”. If you want to know how to create islands and pseudo-islands with the boundary wire, read this article.
What Are the Best Robotic Mowers with Edge Mode?
Which robotic mowers with edge mode can I recommend to you now? This also depends on the size of the area. Therefore I have created a complete overview of robotic mowers with edge mode, which I would recommend. Here you can find them.
Can robotic mowers drive over gravel paths? Robotic mowers should not cross gravel paths, as the mowing unit can be damaged. The robotic mower can also get stuck in very deep gravel. Instead, a mower-friendly bridge or pathway should be created with paving slabs or a passage circuit.
Also interesting: Yard with gravel paths: Safe crossing for your robotic mower
Robotic mowers and trees in the yard. How do the two get along? If there are trees in your yard, it is best to exclude them using the boundary wire for the operation of a robotic mower. Islands can be created with the cable for this purpose. Especially trees with protruding or surface-level roots can cause robotic mowers to get stuck. Furthermore, it is not good for the bodywork if it constantly bumps into trees.
Also interesting: Creating islands for robotic mowers: Manual with graphics
Are you looking to buy a robotic lawn mower? I think there has never been a better time, since the most recent models on the market are actually quite sophisticated so that it can now be appealing...
High-end robotic lawnmowers can be a significant investment, so I was curious about how often they get stolen and did some research on the topic. Although there is no specific data available on...