8 Things To Consider Before Buying A Robot Lawn Mower

The market for robotic lawn mowers has grown significantly over the last few years and forecasts suggest that it will continue to grow strongly for many years as the technology improves and prices decline. Innovations continue at a rapid pace, and there are many new features being developed and integrated into each new model on the market. There are a number of features which must be taken into consideration prior to making a decision about which robot lawn mower is best for you and your garden. Read on to learn about the factors you should be taking into consideration.

Size Of lawn And Battery Size

The size of your lawn is a very important consideration to think about when purchasing a robotic lawn mower. Lawns come in all shapes and sizes, and consideration of this fact is crucial when deciding on a robotic lawn mower.

Many of the entry level models come with smaller batteries that are only designed to cut small to medium sized lawns, typically starting at models that will cut up to 400 square meters. Larger models can cut considerably larger lawns, up to 3000 square meters or more.

Obviously the mowers that are able to cut larger lawns require larger batteries, more powerful motors, often larger cutting blades and more sophisticated software, and as a result of this tend to be considerably more expensive than entry-level models for the smaller garden.

Gradient Of Slope the Robotic Mower Can Manage

robot mower slope gradient

The power of the motor in your robotic lawnmower does more than impact the speed of the mower and the area that is able to be cut. A more powerful motor is required to contend with steeper gradients. I have generally found that even the entry level models will manage quite steep slopes, but for anyone with a particularly hilly garden, you will need to take the steepest gradient into consideration and choose a model that is going to be able to manage to adequately cut your lawn.

For those people with very steep gardens, you may wish to calculate the slope of your lawn before purchase, to ensure that your chosen model will be able to handle your lawn. I have written a quick guide to calculating the slope of your lawn here. 


All robot lawn mowers have a number of safety features to prevent people, pets or unexpected items from being injured or damaged while the lawn mower is working. All robot lawn mowers are programmed to stop when they hit an obstacle, usually backing up, turning and moving away from the obstacle as a result.

All robot lawn mowers have lift and tilt sensors fitted, which cause the blades to stop automatically if they are lifted or tilted sufficiently. The blades of robot lawn mowers are also tucked well underneath the body of the mower, meaning that they cannot be accessed without lifting or tilting the mower. This means that if an inquisitive pet or small child should try to interact with the lawn mower, the blades will stop immediately and the risk of an injury is eliminated.

Conventional lawn mowers are consistently the garden appliance which causes the most injuries. Robot lawn mowers on the other hand, despite having sold more than one million units since their introduction, have not caused any injuries requiring attendance at an emergency department. Safety features do differ between individual models and between manufacturers, so this is an area you may wish to look at in more detail. I have written an article discussing the safety features of robot lawn mowers in more detail here.


Most robotic lawn mowers have a control panel which allows you to adjust variables such as cutting days and hours and the height of the blades. More advanced models are available with built-in Wi-Fi and smart features which allow you to monitor and control the robot lawn mower from your smartphone or tablet.

Some models have weather sensors, so that they will avoid cutting the grass in rainy or wet conditions. Some models can also inform you if the lawn mower gets stuck. Entry level models come with fewer features, but the trade off is the more appealing price required for purchase.


When looking to purchase a robotic mower, it is important to consider the security features of the available models. Almost all have PIN code locks, and many also have alarm features. Newer and premium models also have a GPS tracker on board. These features are particularly important when your garden is not secure and can be accessed easily by intruders. Most manufacturers are also able to blacklist your mower if it is stolen, therefore making it impossible for the thief to service the device in the future.


example of complicated lawn with obstacles for robot mower

Automatic lawn mowers are designed to cope with all different shapes and sizes of lawns, and even lawns with multiple obstacles, such as trees or flower beds. The more complex your garden is, and the more obstacles that are within the area to be cut, the more time and effort required to properly install the perimeter wire prior to the functioning of your robotic lawnmower. While this may seen off putting, it only has to be done once and will ensure that your mower works flawlessly all through the cutting season.

Garden Complexity

Robotic lawn mowers tend to work best for simple shaped lawns.  The more complex your lawn is, the more difficult your mower will find it to navigate to all areas of the lawn and ensure an even cut. Automatic lawnmowers find narrow sections of lawns most difficult to navigate through due to the cutting algorithms that are used to determine the direction that the mower will go next. As a result of this, most models have a guide wire which makes it easier for the robot lawn mower to navigate your lawn and ensures that all areas are cut.

The guide wire runs from the base station across the middle of the lawn, to the furthest point of the area to be cut. When the mower sets off to cut from the base station, it will use this guide wire to help it find the far side of the garden, to ensure that all areas are cut. Similarly, when the battery is low and the mower has to return to the base station, when it passes over the guide wire, it will detect this and follow it back to the base station by the most efficient route.

Installation of a guide wire is much the same as the installation of the perimeter wire, and although this increases the installation time, I believe it is a feature that is very important to look for in an automatic robot lawn mower.

Weather Protection

extreme weather and robot mowers

Most robotic lawn mowers are suitable for use in all normal weather conditions. Manufacturers usually advise bringing your lawnmower in during extreme weather conditions, such as torrential rain and storms. Robot lawn mowers also generally shouldn’t be exposed to freezing weather conditions, so in winter or in particularly cold conditions it is advisable to bring your lawn mower into a warmer environment such as a shed or garage.

There are many other factors that you may wish to consider before making the decision to purchase an automatic lawn mower. Hopefully this article provides some food for thought as you continue to research what is right for you and your garden. If you have any questions about robot lawn mowers or are trying to pick the best one for your garden, leave a comment and I’ll do my best to help.