Do I have to lay the boundary wire underground?
For most robotic lawnmowers, laying the boundary wire is a prerequisite for initial start-up. Of course, laying it underground is a bit more complicated than laying it above ground. Therefore, many hobby gardeners ask themselves: do I really need to lay the boundary wire underground?
The vast majority of robotic lawnmowers navigate using a boundary wire. This tells the robotic lawnmower via a signal which areas are to be mowed and which are not. Laying the cable is therefore the most important step before the mower’s first start-up. For many first-time owners of a robotic lawnmower, this raises the question of whether it is really worth the effort to lay the cable underground or whether the above-ground variant will suffice.
Laying the perimeter wire is probably one of the most important steps on the way to a functioning robotic lawnmower unless it is a robotic lawnmower with a grass sensor. Here, the wire serves as a signal generator for the device, so that it is clear which areas the robot should traverse, and which are no-go areas. If the robotic lawnmower drives through a flower bed or falls into the garden pond, there will be negative consequences. Accordingly, the first step is to mark the obstacles that the robotic lawnmower cannot detect due to natural barriers. Precise installation of the wire around the edges of the lawn is even more crucial when the mower has edge cutting capabilities for a fine finish.
However, not all laying is the same. There are two different methods: each that come with some advantages and disadvantages. The above-ground version is much easier and faster but is also more prone to damage. With that being said, it is by no means necessary to lay the boundary wire underground. Sometimes it just lends itself, as the extra effort also brings some benefits
How the perimeter wire works
The perimeter wire is fixed to the charging station and laid once completely around the lawn before arriving back at the charging station. The charging station sends out a low but perceptible electrical signal through the wire, which creates a magnetic field and serves as an orientation for the robotic lawnmower to navigate. For this to work properly, two aspects in particular are important:
- The perimeter wire must not be damaged.
- The maximum length of the manufacturer’s specification must not be exceeded.
Quick start with easy installation
The start-up of a robotic lawnmower itself is very simple. You simply place the charging station in a suitable place in the garden, connect it to the electric grid, lay the boundary wire around the lawn and use the quick installation of your robotic lawnmower. This helps to define the mowing times, for example.
The first test run can already begin. Laying the boundary wire is probably the most time-consuming of the tasks you will face before the first test run. You have two different options:
When to lay the perimeter wire above ground
The above-ground installation of the perimeter wire is undoubtedly the simpler option. You simply lay the wire once around the lawn (be sure to include flower beds and other obstacles from the outside) and simply fasten the wire to the distance specified by the manufacturer along the lawn edge with lawn nails. The lawn will grow and cover the wire in about 2-4 weeks, and will then become almost invisible.
Advantages of the above-ground laying of the perimeter wire
First, one clear advantage is that mistakes can be swiftly corrected, and you can quickly make changes to the layout (for example) when redesigning the garden.
If, after the first laying, you find that the lawn edges need readjustment because the distances may not be correct or the effort required for retouching is too great, the perimeter wire can easily be moved.
Disadvantages of laying above ground
Nonetheless, when the perimeter wire is laid above ground, it is also permanently exposed to external influences such as rain, ice, and snow. The risk of corrosion and weathering is incomparably higher than with underground laying. Over time, the wire can become permeable and may break. In this case, the only solution is repair, which is comparatively easy to underground installation.
At the same time, a properly tautly laid cable also carries the risk of being damaged during gardening work such as scarifying or when digging up flower beds. The blades of the scarifier or a careless spade can easily cut the cable, so caution is always critical. Other burdens, such as those caused by traction wheels or the blades of a lawn robot, on the other hand, generally do not pose a problem for the perimeter wire when the cable is laid properly.
Underground installation of perimeter wire
It is probably indisputable that a wire that is buried underground is less affected by the elements. This raises the question whether it makes sense to lay the cable underground as a matter of principle. Most manufacturers and 3 rd part providers offer professional underground installation services.
Advantages of underground laying
In addition to the lower risk of damage from wind and weather, one advantage is that the wire is invisible underground, significantly reducing the risk of damage from a scarifier or other garden tools. This means you can carry out gardening work worrying less about the perimeter wire.
Another advantage is, of course, the inconspicuous appearance. The cable is invisible even under paved passages, as you can simply run it under the stones. Most cables can transmit their signal with minimal problems up to a depth of about 7 centimeters.
Disadvantages of underground laying
The disadvantages of underground installation are obvious. Once the wire is laid, a change in your garden design turns out to be comparatively complicated, as the cable has to be dug up each time. In the event of an accident, this also makes troubleshooting more difficult if the cable has to be uncovered again. Wire breaks are not easy to detect visually, so a tool is always needed to locate the signal interference.
And, of course, the laying itself is also more complex. An initial channel, approximately 4 cm deep, must be dug for the wire. This usually works quite well with a lawn edger. However, unconventional methods such as discarded angle grinders or chainsaws are also suitable for making the channel. Those who do not want to make the effort themselves, but do not want to give up the convenience of underground laying, can hire a specialized company for this purpose. They have the correct equipment for digging. In any case, the channel should be laid to a uniform depth. Otherwise, the edge drive will be somewhat less accurate than when laying above ground.
Laying boundary wire. what to keep in mind
For both underground and above ground laying, the wire should be tautly stretched. It must not cross at any point, otherwise signal interference may occur and cause the robotic lawnmower to become disoriented. This is especially important if you include flower beds and the like in the center of the lawn in the induction loop, where the wire is routed from the outer edge to the center of the lawn and back.
Finally, it is important to keep the distances of the lawn edge and walls according to the manufacturer’s instructions. This will help minimize lawn-edge retouching and prevent damage to the robotic lawnmower.
Laying boundary wire underground for a rolled turf
It seems tempting to simply place the wire under the turf when laying the sod. However, this carries a r risk, as you won’t be able to test the functionality of the wire until the turf is in place. This means that troubleshooting can turn out to be costly.
We recommend placing the wire above ground first and starting the robotic lawnmower. This way, any problems can be detected in the first few days. It is important to know that after laying the sod, you have a 3-week window to place the perimeter wire underneath. After that, the rooting can become too strong.
As an alternative to simply sliding the wire under the sod, it’s perfectly okay to dig a channel in the grass where you can place the wire. This way you are completely independent when you dig the channel or when you purchase your robotic lawnmower.
Note, if you prefer the above-ground option, it is just as feasible with sod as with any other lawn.
Advantages and disadvantages for installation methods
Both above-ground and underground laying of the perimeter wire has advantages and disadvantages.
- simple and quick installation
- changes in the design of the garden can be easily made
- repairs are easier, as a broken wire can quickly be detected visually
- weather influences
- risk of damage by scarifiers and the like
- visually annoyance in the first weeks
- wire disappears visually from the overall picture immediately after installation
- less chance of damage by scarifiers and the like
- less wear and tear due to weather conditions
- laying is more time-consuming / more expensive (with a professional installer)
- troubleshooting can be complicated
- a change in the garden design can be costly
When is underground laying recommended
There is no answer to this question. It is simply impossible to give a blanket answer as to whether above ground or underground laying is better. It is certainly an ideal solution for gardeners who prefer an unobtrusive overall appearance, knowing that the garden design is completed for the coming years. To make sure that the robotic lawnmower works properly, it is also a good idea to install it above ground first. Although this involves twice the effort, it can help reduce the potential for errors afterwards. Anyone who is afraid of the hassle of laying the grass themselves can call in a professional service to do the work.
Lawn owners who regularly scarify their lawns are also better off laying the wire underground. After all, this helps minimize worry about accidentally cutting it with gardening equipment.
Conversely, above ground installation is recommended for people who like to remain flexible and prefer both easy installation and quick troubleshooting. over, any repairs can be done quickly, and the visual impact on an overall, harmonious appearance disappears after a few weeks.
The best cordless lawn mowers in 2023
Looking for the best cordless mower? Browse our experts’ pick, from budget to premium models.
A lawn mower may be one of the first purchases we make when getting a garden of our own, but that doesn’t mean finding a good quality one is easy. There are so many models and brands on the market to choose from, including corded electric and petrol, but as their range increases and fall, cordless, battery-powered models are an increasingly popular option.
Light and compact compared with traditional petrol models, cordless mowers are simple to use, easy to manoeuvre around the garden, and have none of the maintenance and servicing needs or costs of petrol lawnmowers. Powered by a rechargeable lithium-ion battery, which charges up quickly and won’t lose power in storage, they’re also quiet and emission free.
To compare these cordless mowers against other types of mower, we’ve reviewed the best lawn mowers, robotic lawn mowers, electric lawn mowers and push mowers, too. And if your lawn needs a bit of attention, our experts have tested a range of the best manual and powered aerators and scarifiers.Keep edges looking neat with our pick of the best strimmers, the best garden shears and the best lawn edging, and if you’re thinking about somewhere to store your new mower, our comprehensive guide to choosing the best garden shed will be helpful.
For your next DIY project, have a look at the best cordless drills.
The best cordless mowers to buy at a glance
Cordless mowers. Buyer’s Guide video
Many thanks to Rosie Yeomans and Sparsholt College for their help in making this video.
Getting the best cordless lawn mower for you means ensuring it has the correct cutting width, range of cutting heights, and weight plus a battery run time that matches the size of your lawn. We’ve tested a range of cordless push mowers, putting them through their paces across a range of grass and terrains, to help you find the right one for your garden.
Each mower has a detailed list of pros and cons for clarity and has been rated according to set up and storage, handling, mowing and value for money. Every mower in our round up below has scored a minimum of four out of five stars, so you can buy with confidence.
In every review we award outstanding products our coveted Best Buy award. To see these and the others we recommend, browse our pick of the best cordless lawn mowers, below.
Best Buy cordless mowers
Husqvarna Aspire LC34-P4A
Our rating: 4.9 out of 5
- Cuts even long grass with ease
- Battery level visible while mowing
- Small and compact for easy storage
- Part of the POWER FOR ALL cordless range
Part of the new Husqvarna Aspire cordless range, which includes a hedge trimmer, pruner and leaf blower, this 34cm mower is powered by an 18V POWER FOR ALL ALLIANCE battery and charger. These are interchangeable with tools in other leading brands such as Flymo, Gardena and Bosch so if you also invest in tools in these ranges, you’ll only need to buy the bare tool and won’t have different batteries and chargers taking up space in the shed.Great for small gardens the mower comes ready to go, there’s no assembly or handles to attach, and it folds down to a compact size when you’re finished, with a telescopic handle that folds completely flat over the body of the mower. It can then be stood up against a wall or hung up, and even comes with a handy hook. The 30l grass bag also flattens down to take up very little room and can be hung on the mower. The Aspire is light, with a carry handle so that lifting it up steps or into other areas is easy and it has an adjustable handle to suit different height users. It’s comfortable and easy to manoeuvre around the garden and has just four cutting heights to choose from, ranging from 25-65mm and changed easily with a single lever on the body of the mower. It cuts grass quietly and smoothly and has an automatic boost that increases blade speed when you’re mowing in tougher, longer areas that works well. You can hear it kick in when you push the mower into longer grass and unlike other cordless mowers that can cut out, just carries on cutting the grass. While you mow the battery charge level is always clearly visible so you know how much battery you have left and when it needs charging. It comes with a two year warranty and we awarded it a BBC Gardeners’ World Magazine Best Buy in 2023 for ease of use.
Specs: Battery: charge time. 95 mins; run time. 500sqm. Cutting: width. 34cm; height. 25-65mm. Grass box. 30 litre.
Buy the Husqvarna Aspire C34-P4A cordless mower from Husqvarna and Sam Turner
Our rating: 4.5 out of 5
- Easy to assemble and use
- Comfortable padded handle
- Choice of mulching or collecting clippings
- Interchangeable battery with Greenworks 24V family
Ideal for smaller gardens this sturdy, great value cordless mower is easy to put together, well thought out and simple to use. Thanks to a padded handle it’s comfortable to push, although it did feel a little short for our taller tester, and it’s light and easy to manoeuvre around trees and beds and borders. There are five cutting heights to choose from, adjusted with the simple lift of a lever and it offers the choice of collecting clippings in the 30 litre fabric grass bag or inserting the mulching plug and leaving them on the lawn to break down and feed the grass. It mows well but doesn’t like very long grass, with the battery cutting out occasionally but its long lasting brushless motor offers a a decent run time of 46 minutes and it charges in two hours. Plus, as part of the Greenworks 24V family, both the battery and charger are interchangeable with all the other tools in the range, saving you money if you invest in more in the future. We awarded it a BBC Gardeners’ World Magazine Best Buy for the best budget cordless mower in 2023.
Specs: Battery: charge time. 120 mins; run time. 46mins. Cutting: width. 33cm; height. 25-70mm. Grass box. 30 litre.
Yard Force LMG37A 40v 37cm
Our rating: 4.8 out of 5
- Rear roller
- Double folding handle for easy storage
- Quickest charge time
- Part of the Yardforce GR40 cordless range
This sturdy mower has a 37cm cutting width and useful features including a rear roller for those much desired stripes. Awarded a BBC Gardeners’ World Magazine Best Buy in 2022 for small to medium lawns, clippings are collected in the large 40 litre fabric grass bag. It offers a wide choice of seven cutting heights, from 25-75mm, and is easy to fold away at the end of the day. The 40V battery is quick to charge, taking just 50 minutes and when full it has the capacity to cut a 400m2 lawn.
Specs: Battery: charge time. 50 mins; run time. 400sqm. Cutting: width. 37cm; height. 25-75mm. Grass box. 40 litre.
Buy the Yard Force LMG37A 40V 37cm cordless mower from Yard Force, Amazon and Wickes
This Is How Many Amps an Electric Mower Needs
You might be considering switching to electric lawnmowers as a quieter and more environmentally friendly solution. However, electric mowers have some specific requirements you should be aware of.
An electric corded lawnmower typically draws between 6 and 12 amps from a standard outlet. The amp rating helps you understand your mower’s power and what kind of wire gauge to get. On the other hand, Cordless mowers have batteries that can provide 18 amps per hour on average.
In the rest of this article, I will explain more about the amp requirement of electric lawnmowers. Additionally, you can learn more about your lawn mower, including power requirements and what to look for in an electric mower.
Check out the DynaTrap Mosquito Flying Insect Trap – Kills Mosquitoes, Flies, Wasps, Gnats, Other Flying Insects – Protects up to 1/2 Acre (link to Amazon).
How Many Amps Should an Electric Lawn Mower Have?
Understandably, electric lawn mowers need to draw power from an outlet to function. However, the amount of power that they need to draw is limited and depends on the type of lawn mower you’re looking for.
According to US regulations, electric lawnmowers can’t draw more than 15 amps from an outlet (source).
This is more of a theoretical limit set by regulations; typical electric mowers draw somewhere between 6 and 12 amps from standard outlets, with most mowers having an amp rating of around 10.
Why the Amp Rating of Your Lawn Mower Matters
The amp rating indicates how powerful your electric mower can be; a 12 amp mower can be used to cut tall and tough grass, while a 6 amp one would not do a good job in this case. You can find out the amp rating of your lawn mower before buying it; it’s usually written somewhere visible, like a sticker on top of the mower or in the user’s manual.
You need to know the amp rating of your electric lawn mower because it helps you decide what gauge or type of extension cord is suitable for your mower to work properly.
The more amps your mower uses, the more power the extension cord will have to withstand. The general rule is that the higher the power of the mower, the lower the wire gauge number that you need.
For instance, for a mower with a low amp rating, like 6, you might get by with a 16 gauge extension cord (link to Amazon), while for another mower with a higher amp rating–say, 12–you should get a lower number.
The distance from the power outlet also plays a role. The longer the length the current has to travel, the lower should be the number on the wire gauge. Simply put, a low-number gauge can handle more power and longer distances.
How Much Power Can Your Electric Lawn Mower Use?
In terms of power, an electric lawn mower typically uses between 700 and 1500 watts of electricity per hour, with the majority using around 1000 (source). The wattage of your electric lawn mower is essential to know because it can give you an idea of how much you’re going to pay in energy bills.
You can ask about the wattage of your lawn mower prior to buying it or search for it in the user’s manual or the manufacturer’s website. Naturally, the higher the energy usage, the more it’s going to cost you to mow your lawn.
Knowing the number of amps a lawn mower typically should have, the power it can use, and the above rules about wire gauges and distance help you make an informed decision.
What About Cordless Electric Mowers?
If you want to use an electric lawn mower but don’t want to be limited by a cord everywhere, you may opt for mowers that use rechargeable batteries. Cordless mowers use batteries to work without burning gas or having a power outlet nearby.
The most important advantage of cordless mowers is the fact that they give you improved mobility and a wider range in your mowing. (See Gas vs Electric: 6 Reasons To Use Battery-Powered Yard Tools).
The power that the batteries of these mowers produce ranges between 20 and 120 volts (source). Depending on how long you plan to mow your lawn and what kind of grass or weed you want, you can decide on the appropriate voltage.
Generally, for greater performance, especially cutting tougher grass, you may need a voltage over 70.
However, since the power stored in batteries is finite, you need to recharge the batteries once in a while. You may even have to stop in the middle of mowing if the battery’s run out.
A recharge may require one or two hours, or even more, if the battery is older. The amp hour rating of a typical lawn mower battery is around 18Ah, meaning that it can provide 18 amps of current for one hour.
A cordless electric lawn mower is a good choice if you want better range and mobility while mowing or if you don’t have access to any power outlets. The batteries need recharging, but if you wish, you can keep spare batteries so that you can continue mowing even if your mower’s battery runs out of power.
What To Consider When Looking for an Electric Lawn Mower
If you’re looking for an electric lawn mower but don’t know where to start, it would be helpful to know a few aspects you need to consider in the first place (source).
- Corded or cordless. As I explained above, take into account the size of your lawn and the availability of outlets.
- Deck width. The larger the size of your lawn, the bigger the mower should be so that you can mow your lawn more quickly.
- Material. A deck made of plastic can make the mower lighter, but a metal deck will last longer and withstand every kind of weather.
- Features. You can decide if you want larger wheels, a more extensive range of adjustable heights, and other accessories that can improve your lawn mowing experience.
When searching for an electric mower, you should keep in mind some general stats that can help you make an informed decision. Generally, an electric mower should have between 6 and 12 amps and use between 700 and 1500 watts of electricity in an hour.
Other important aspects to consider would be going corded or cordless, the size of the deck, the material of the deck, and the features of the mower.
Willie writes on small engine repair, landscaping, and lawn care. He owned a professional lawn care business in Alabama for almost 10 years.
What Happens If You Run Over An Electric Mower Cord?
Using an electric mower is a great way to maintain your lawn, but a few risks come with it. The main one is running over the electric mower cord while you’re mowing the lawn. Electric mower cords are made with heavy-duty materials and are meant to withstand some damage, but there are still risks to be aware of.
Is Mowing With A Corded Lawn Mower Dangerous?
The main risk that comes with running over an electric mower cord is electrocution. If wires are exposed and the metallic blades come into contact with them, it could send an electric shock through the mower to you.
The following article is a brief guide explaining the dangers of running over an electric mower cord and what to do if this does happen. It also includes a brief analysis about if cordless lawn mowers are safer to use.
Dangers of Running Over an Electric Mower Cord
Electrocution is the main danger that can come from running over a lawnmower cord. It occurs when the high-speed blades tear open the cord and an electric shock runs through the mower and to you. This can result in multiple health risks and even death.
How to Find a Broken Underground Wire for Husqvarna Automower
Lawnmower blades spin at very high speeds, usually between 2500 and 3000 RPM, equivalent to 200 miles per hour. Since they spin at such high speeds, they can damage and tear almost anything they encounter, including the power cord.
Once the power cord gets caught on a blade, it’s tough to remove. The blades will continue spinning until either there is no more cord left to eat up or the cord gets tangled in the mower and stops the blades.
The wires in the cords will then get exposed and likely cause an electric shock to run through the mower. This electric shock could reach you and result in electrocution. The health risks that come with electrocution include:
Electrocution can also result in death in extreme cases, but that likely won’t occur if you run over a mower cord.
What To Do If You Run Over an Electric Mower Cord
If you accidentally run over an electric mower cord, DO NOT try to remove the cord from the mower’s blades if it’s tangled. The best way to make sure the cord does not have power running through it is to switch off the breaker. Then make sure the mower is turned off on the machine.
After running over an electric mower cord, the first thing you should do is make sure you haven’t gotten electrocuted. If you aren’t experiencing any of the symptoms mentioned above, then it’s likely you weren’t affected.
If you are experiencing slight symptoms, it’s recommended to call your doctor, apply gauze to the wound, and try not to move the affected area as much as possible. If the shock and symptoms are severe, you will need to go to the emergency room as soon as possible.
Once you make sure you aren’t experiencing any health risks, the next step is to make sure that power is not running through the cord. Turning off the breaker is the safest solution. Once the power is removed from the cord you can then make sure the lawn mower is turned to off.
Important: Never touch a cord that has been run over without ensuring the power has been shut off to the cord. Also, avoid reaching under the mower to untangle the cord without making sure that no power is supplied to the machine.
Are Cordless Lawn Mowers Safer?
Cordless lawn mowers are safer than corded mowers since they don’t have a cord you can accidentally run over. They also are more maneuverable which can lead to a safer mowing experience as well.
The main pros of cordless lawn mowers include the absence of a potentially dangerous cord and being more energy-efficient than corded mowers.
Cordless lawn mowers are usually powered by a rechargeable battery, meaning you don’t have to draw as much electricity from outside sources every time you use it. And since they don’t need a cord to function, you don’t have to worry about accidentally running it over, which makes them safer to use.
How to find a break in a Husqvarna robot mower boundary cable
However, some cheaper cordless mowers aren’t as powerful as corded mowers and have a shorter running time. So, if you have a large yard or particularly tough grass, then a quality cordless mower, or a corded mower might be best for your needs. Overall, both mowers are good options as long as you are careful while using either of them.
All lawn mowers, cordless, corded, and gas, can be dangerous. Being aware of potential dangers can help you operate the mower carefully and correctly, and avoid any damage to the mower and yourself.
Always be sure to read your lawn mower operators manual to understand what safety precautions you should take with your lawn mower.
If your yard is small, and you are looking at purchasing an electric lawn mower, be sure to check out our article The 10 Best Electric Lawn Mowers For Small Yards. We provide you with the best options on the market for taking care of your yard.