A strimmer is a useful piece of garden kit for the spring and summer when the grass grows most. It makes an excellent complement to a push, ride-on or robotic lawn mower. Lawn mowers rarely get right in to the edges of flowerbeds and fences, or into stony areas. That's when you get out the strimmer to tidy up.
A number of different types of strimmer are available. They can have a range of strimmer tools, together with different power sources (battery or mains). Historically, strimmers were petrol driven, but now battery strimmers have completely taken over. You can choose between line spool or plastic blade types. There are also models where you can use both types on the same machine. Plastic blades are useful if you have slightly coarser grass and weeds, as they can cope with tougher jobs and don't wear out as quickly. But line is useful for efficiently clearing large areas, because you can adjust the length of the line. However, if you pull it out too far it will quickly snap off. The advantages of a battery-powered strimmer over mains power is that you don't have to deal with extension cables. On the other hand, you have to recharge it regularly. So it's important to choose a model with a short charging time and sufficiently long cutting time, bearing in mind your finances and your garden's strimming needs. Mains powered machines can be handy if you have a smaller garden or only need to clear areas close to the house, because then you don't have to worry about the operating time. But even here the best alternative is probably to buy a battery-operated machine with a slightly smaller battery.
You can also buy brushcutters. The difference between these two garden tools is that a brushcutter is primarily intended for removing undergrowth or even small trees. However, the majority of them can also be equipped with line spools and used for strimming grass. The price for a brushcutter is significantly higher than for a dedicated strimmer, which is only intended for trimming grass and removing minor weeds. A brushcutter is petrol operated and, confusingly, is also sometimes also called a strimmer. The advantages of petrol operation is that you can quickly get going again when the fuel runs out. And the disadvantages are the exhaust, the noise level and the fact that petrol is relatively expensive.
All strimmers were used to cut grass and larger areas of weeds. The ultimate challenge was areas of tall nettles and young thickets of wild raspberry bushes. However, for the majority of the time they were tested on different types of tall and short grass. They have also been tested on wet grass.
We investigated the following parameters:
Performance – What height grass can the strimmer cope with? Does it strim as effectively throughout its battery life? How quickly can it cope with clearing different types of grass? How does the result vary when the grass is damp?
User-friendliness – How easy is it to assemble the strimmer? How easy is it to start? How can you adjust it? For example, is there a telescopic handle and can you set the strimmer head in different positions? Does it have any functions that mean you can go close to sensitive objects without damaging them?
Ergonomics – Can you strim throughout the entire battery life without getting pains anywhere in your body? How stable does it feel in your hands? Is it easy to use in inaccessible spots? What are the noise level and noise profile like?
Battery life and charging – How long does the strimmer run before you have to recharge it? How long does it take to charge the battery? Can you see how much battery life there is left? Can you see how much it has charged?
The Ryobi RLT183225 is best in test because of its long battery life and effective strimming, making it extremely good value for money. Despite its long battery life, it's never too heavy for your back or painful on your hands. It also runs at maximum throughout the battery life and doesn't start to lose power towards the end. The rubberised handles give a good grip. The build quality feels solid, without any strange noises or instability in any parts when we wiggle or pull on them. It's easy to set the handle and strimmer head in the right position. However, it can sometimes be difficult to get the battery out of the attachment on the strimmer. We'd also have liked a plant protector to be able to get as close as possible to sensitive objects.
The RLT183225 is powerful and can cope with averagely difficult terrain. It deals with thick clumps of tall grass and weeds despite coming with a spool of line instead of plastic blades. However, it struggled a bit when it came to thickets of small wild raspberry bushes. For a strimmer, however, it does a more than acceptable job. The spool of line lasts for about seven medium-tough sessions with lots of grass and some weeds before you have to replace it. Replacing the spool is simple. However, something that's a little less pleasant is the strimmer's noise profile, which is quite strident. Another negative factor is that on a couple of occasions the line wasn't fed out enough so we had to pull it out by hand. But given the quality of the strimming, and above all how long it strims before the battery gives up, this is a really good purchase in the 18 volt class.
The Gardena Li-18/23R is a strong strimmer that's easy both to install and understand. It's supplied with plastic blades instead of a spool of line, together with a set of replacement blades. As standard, a blade is attached to the strimmer head. The blades handle everything we expose them to – from normal grass to tougher undergrowth and thick clumps of wet grass. But it wears out quickly. It gets significantly abraded even during the first strimming session. After this, the strimmer isn't really as efficient when strimming, as the more stubborn strands remain and you have to strim the same area several times. However, it can still cope with relatively coarse and more stable undergrowth. The blades then work for a further 3-4 sessions before they really need changing. They're very simple to change, with a simple click-in function. The installation of the strimmer is also very straightforward. All parts are snap on, so no tools are required. It's also easy to adjust the handle and the angle of the strimmer head. In other words, user-friendliness is high from start to finish. The strimmer is also relatively light.
The aspect we found to be negative about the design is that it's bulky and plasticky. The entire trimmer somehow gives a cheap impression. It could have been neater and had more rubberised details at the adjustment points. However, the battery life is good. The included battery gives you a cutting time of 25 minutes, which is very good. The battery is charged using a very small, neat charger. The battery also has an indicator that shows how much it has charged. However, we never really got this to work as it always seemed to show half full on our example even when the strimmer battery was completely flat. But the Gardena Li-18/23R is a powerful and very user-friendly strimmer with a very long cutting time. If it had received a little more love in terms of sustainability in the blades, it would have received top marks, but it's still a very good buy.
The AL-KO GTLi 18V Comfort is a strimmer with a spool of line that strims effectively and can cope with extremely tough terrain despite using wire instead of plastic blades. It can even cope with minor undergrowth such as young raspberry bushes and thicker weeds. However, it's not as efficient on wet, tougher grass. It has a useful automatic line feed feature. The line spool lasts for about five medium-tough sessions, mainly consisting of grass trimming, but also with some weeds, before it's time to replace it. It comes with an extra spool of line on the strimmer arm and you don't need tools to replace it. The build quality is generally quite high, although the line wears out quite quickly. The accessories included make this a serious machine, for example with an edging wheel and a metal plant protector instead of just a metal plant protector, and rubberised parts at points where you might hold the machine. The edging wheel makes it easy to go close to sensitive objects without damaging them, as the machine runs around them instead. Some of our testers found the GTLi 18V Comfort to be rather heavy. They also quite quickly developed sore hands and wrists, which we suspect is the result of slightly too much resistance in the handle. But we can't complain about the noise profile.
However, the cutting time isn't good, being slightly under average, and we'd have liked a few more minutes for it to get more points here. This is an extremely important aspect, so the score drops quite a bit. Another major disadvantage is that the battery doesn't have an indicator. However, the charger is small and neat so you can easily store it away when not in use, and the plug has an indicator light that shines green when the battery is fully charged. Overall this is a reasonable tool which would have had a much better score with a longer battery life.
The Stihl FSA 45 is a strong strimmer with double plastic blades in the head which clears both grass and tough weeds very effectively. You can easily replace the plastic blades by unclipping them from the strimmer head and clicking in new ones. It includes a couple of extra blades, which are tidily attached to the machine. You don't get many, but on the other hand they're very tough and you only need to change them every four or five sessions. You can also install a spool of line instead of plastic blades onto the same strimmer head. Assembly of the strimmer itself is very straightforward and only requires two screws. However, the battery is built-in and you can't disconnect it for charging – instead you have to plug in the entire strimmer. Nor can you change batteries with other products from the same manufacturer or swap between two batteries so that you can quickly get back to work. The FSA 45 is also special in another way, in that it includes a small plastic "key" that has to be inserted into the machine before it will start.
The FSA 45 is a neat strimmer in terms of size, and feels well-balanced and light when you hold it. Ergonomically, the user-friendliness is good. However, when it comes to actually cutting the grass, it's considerably less easy to use. This is largely because you have to slide a button forwards while at the same time holding in another button and handle to start the machine. But it also comes completely to a stop every time it runs into too much resistance. In other words, you can't simply lift the strimmer head to get it started again. This means that you have to do the starting hand movement over and over again during one session. This rapidly tires out both hand and wrist and can lead to cramp. Because it has a key that you can pull out as a safety function, we think that this is unnecessarily fussy. The battery life is good and it runs at full speed during the entire session. The machine is also very quiet.
The Bosch AdvancedGrassCut 36 is a strimmer that maintains a nice, quiet noise profile and which can cope with normal amounts of vegetation in a time-efficient manner. This strimmer easily removes long, dry grass in a short time. The same applies to weeds such as young raspberry canes and sparse nettles. But for a 36-volt machine we would have expected better performance. It's immediately obvious that it has to struggle where the grass is more dense and greener. Particularly if it's a bit damp. This makes the noise immediately a bit more obvious. After a while it starts to get stuck in the grass rather than chopping it off, which makes it jerk irritatingly. However, the cutting time is reasonable and the line reel lasts for a long time, even though the machine tends to feed out more line a bit too easily on some occasions.
In terms of design, the Bosch AdvancedGrassCut 36 is stable but a bit unwieldy. For example, it feels rather chunky and front-heavy. We would have liked it to include a harness. At the same time we didn't encounter any loose parts or strange noises. The strimmer is easy to assemble, and equally easy to adjust. However, the throttle in the handle is unnecessarily large and a bit too stiff. And it also runs a bit more slowly if you don't keep it completely depressed. This function is probably intended as a kind of environmental function that allows you to run the machine more economically at lower speed, but we'd have preferred this to be controlled via a button. The function means that when you've run the strimmer for a while and lost a bit of force in your hand without noticing it, the motor will slow down and give you a worse cutting result. Just like in tougher vegetation, the result is that it can't cope with cutting the grass properly - instead it gets stuck. But the AdvancedGrassCut 36 is otherwise a perfectly acceptable strimmer. If you have good grip strength and a garden where weeds and grass aren't too dense, this is a good strimmer.
The Stihl FSA 56 is a neat but also relatively strong strimmer that's easy to carry. At the same time it feels sturdy and stable. The strimmer can cope with relatively thick tufts, and has no problems with tall grass. It's time efficient on larger grass surfaces because you don't need to go over the same area several times - at least not as long as the terrain is easy to medium-hard. If the grass is very dense, however, the strimmer isn't quite so happy. It also finds it difficult to deal with thickets of raspberries or nettles - it manages, but you'll have to go over them several times. But the FSA 56 copes with individual tufts of weeds very easily. Unfortunately you can't reduce the strength on easier terrain to save on the battery, which we think this strimmer could do with. The battery life is the FSA 56's Achilles heel, and comes in at a few minutes less than what we think is acceptable. So to get a more reasonable cutting time, you need to buy an additional battery, which unfortunately drives up the price quite a lot, particularly as Stihl's batteries are quite expensive. You can see how much charge there is by pressing on a button on the battery. The range runs from 1-4.
The strimmer line feeds out smoothly when you press the strimmer head on the ground. But the line isn't particularly tough so it wears out quite quickly. The shaft and handle are both adjustable, which makes it easy to find a suitable working angle for both shorter and taller users. This reduces strain as you use the strimmer. Nor did we feel like this machine needed a harness. On the other hand we weren't using it for very long as the battery life is so short. The FSA 56 has grip-friendly surfaces, but unfortunately it also has quite a lot of vibration for an electric strimmer. The noise level is above average but at the same time not particularly loud. The noise profile is a little unpleasant, but not so much that it hurts your ears. Overall, the Stihl FSA 56 is a relatively strong and neat strimmer which is suitable for smaller areas.
The Husqvarna 115iL is best in test because it's a strong strimmer that copes with almost everything we face it with. It trims thick, dense tufts of grass with no problems, and the same applies to weeds such as nettles and misplaced raspberry canes. The only time that the strimmer struggles a bit is when the very dense grass is also damp. Then you can hear from the motor that it's having to work harder, and the speed drops. On these occasions, you sometimes have to lift the strimmer head and repeat areas more carefully. But this is only under extreme conditions. Under normal to difficult conditions, there are no problems with efficiently and quickly trimming large amounts of weed and brushwood. One Achilles' heel is thin tufts of grass which occasionally get stuck in the strimmer head and wind around it. Fortunately this doesn't happen often and even then only with grass that's at least 50 cm tall. Another flaw is that you can't angle the strimmer head, which is a disadvantage if you're trimming slopes.
The Husqvarna 115iL generally has a good design and high build quality. Despite the strimmer being heavy, this isn't something you notice when you're strimming. The balance in the machine is excellent. You can also easily adapt the strimmer to your height by releasing a control, pulling out the lower part and locking the control again. Tool-free solutions like this are user-friendly. It also has good solutions in the two buttons on the top of the strimmer. There's a small but clearly marked power button, together with a button that starts an eco-mode which reduces the strimmer speed. This is handy when you're cutting simple, not too dense vegetation and don't want to use the battery unnecessarily. In this mode, it's also relatively quiet for a strimmer. In normal mode, the noise level is medium-high, but it generally has a nice muffled profile. The 115iL is a powerful, user-friendly, well designed and powerful strimmer that's suitable for homeowners with mixed weeds and grass - primarily on flat ground.