If you have a lawn of any size then a lawnmower will be necessary to keep the grass at a manageable height. Unless you are cultivating a wild flower meadow, but even this will need cutting two or three times a year.
Most domestic lawns comprise of a mix of different grass species, grown together to give the lawn a specific trait, such as a fine lawn, hard-wearing lawn or a shade tolerant lawn. For further details see types of Grasses for UK Lawns.
Regular mowing keeps the grass at a specified height and ensures that the grass mix is kept under control. If a lawn is not mowed regularly and the grasses are allowed to grow out, taller species may become more dominant and crowd-out the finer grasses, resulting in a much coarser lawn. These coarser grasses often have poorer drought tolerance. Once a lawn has reached this stage the only real option is to take-up the whole thing and start again, if you want to return to a fine lawn of evenly clipped, narrow leaved grass.
On the other hand, mowing a lawn too close and too often can weaken taller grasses and even kill them off. This can result in bald patches, especially if the ground is not perfectly level, where high spots are clipped down to soil level - known as scalping. Cutting too short also enables low-growing and spreading weeds to take over, particularly moss.
As a general rule, keep your lawn mowing height above 3/4” (20mm) for most fine lawns, other than truly ornamental ones. If moss or low growing weeds are a problem, raise the height to around 1 1/2 to 2" (40mm to 50mm). During cooler wet seasons and in drought conditions you can raise the height a little more to allow the grass to cope better with these conditions.
It should also be noted that cutting grass by more than a third of its height at one time can easily shock and damage it. Therefore if you want a 2" (50cm) lawn, mow it when the height reaches 3" (75cm) or for a 1" (25cm) lawn, cut it when the height reaches around 1.5" (40mm).
Regular weekly mowing, at a sensible height, enables the grass to thrive, spread-out and become more dense. This helps to prevent weeds and other unwanted species of grass from taking control.
Most gardeners in the UK begin mowing in March and finish in October. Including an occasional light (high) cut in early winter, when the weather is mild. For a top quality lawn it is best to cut it twice a week, when the grass is growing vigorously during the summer. Then cut it just once a week in spring and autumn and under drought conditions.
When it comes to buying a lawnmower, the range of available machines is somewhat bewildering. The final choice will depend largely on the surface area of grass to be cut and to a great extent the type of grasses in the lawn, e.g. whether it is a fine ornamental lawn or a slightly taller and more coarse general purpose lawn.
For small lawns a basic hand push mower or even a combi strimmer/mower could be suitable. Small to medium size lawns can easily be tackled with a mains-powered electric lawnmower.
Battery powered mowers, which can usually tackle an average size lawn on one charge, have the benefit of no cables to get in the way and can be used anywhere.
Larger lawns will require the use of a petrol driven mower and for very large lawns a petrol powered ride-on mower may be necessary.
For general purpose and hard wearing lawns, a rotary mower will tackling both long and short grass equally well. Many rotary mowers also have grass collection facilities. For a finer and closer cut lawn, nothing really compares to a cylinder mower and the more blades it has the better the cut.
Improvements in battery technology over recent years, now mean that modern Lithium battery powered mowers are competing well with petrol powered machines, in both power and endurance. The added advantage of battery power is its lower maintenance requirements, although the initial purchase costs can be higher. However, once you have a purchased set of batteries and a charger, you may be able to use them to power other gardening equipment made by the same manufacturer, such as hedge trimmers, brush cutters, line trimmers and even power tools. So if you are seriously considering a battery powered mower, it may be worth checking out what other types of tools can be powered from the same batteries. Note: battery packs are usually manufacturer specific, so are unlikely to fit other makes of cordless tools.
The following key areas should be considered when choosing a lawn mower:
In general, the wider the cut, the quicker you can mow a lawn of a given size. For the average size lawn, a 12-16 inch (30cm to 40cm) width cylinder or rotary model is adequate. For larger areas a 14-18 inch (35cm to 50cm) machine may be necessary. Ride-on machines can be used to make light work of extensive areas.
It is best to choose a mower where the cutting height can be quickly and easily adjusted. Ideally by the use of an easily accessible lever at the top or side of the machine. As described above, adjusting the cut height is important for maintaining the lawn in different seasons and weather conditions. Also in different areas of the garden, where either a fine or a coarse lawn may be required. Note, most hover mowers and some rotary mowers require the blade to removed and packing pieces added to adjust the height, which can be tricky and difficult to do.
For safety reasons, always switch-off and isolate a lawnmower before adjusting the cut height.
Leaving a large amount of grass cuttings on the lawn is not only unsightly but can damage the lawn if left in thick clumps. You can either rake-up the cuttings and put them on the compost heap or use a mower with a grass box to collect them as you mow. If you mow the lawn little and often, this should produce a much finer layer of cuttings, which can be left on the lawn to compost down, if the weather is fine. However, this is not recommended when the weather is cold and wet as the cuttings will then just lie on the lawn and turn to slime. For this purpose, some mowers come with a mulching plug that can be fitted in place of the grass box. The mower will then shred the cuttings up more finely and blow them back onto the lawn.
Ease of starting and low maintenance is another important feature. Mains electric and battery-operated mowers offer a distinct advantage over petrol driven mowers in this aspect. However, petrol and battery powered machines can be heavy and often difficult to negotiate over steps and ledges.
Cylinder lawnmowers have a number of blades arranged in a spiral, forming a rotating cylinder. Cutting occurs as the rotating blades pass close to a fixed blade, set just below the cylinder - rather like a scissor action. The quality of the cut depends on the rotational speed of the cylinder, how closely the rotating blades pass the fixed blade, and the number of blades on the cylinder. In general the more blades the finer the cut.
Image Credit: Qualcast Corded Cylinder Lawnmower
These either have a single, double-sided, blade or several individual blades, made from toughened metal or hardened plastic. These rotate at high speed slicing through the grass. The effectiveness of the cut depends on the speed of rotation and the blades' sharpness. Rotary mowers that use plastic cutters often need a steady supply of replacement blades, as they damage easily and blunt very quickly.
Both rotary and cylinder mowers can produce a good finish if used correctly, but only rotary mowers are able to cope with cutting long grass. Both types can also produce a striped effect if equipped with a roller behind the cutting blades. Stripes result not from the cutting action but from the roller pressing down the grass in the direction of travel.
Image Credit: Bosch Rotak 37-14 Ergo Electric Rotary Lawnmower
Hover mowers work on the principle of creating an air cushion to glide over the surface of the lawn. A rotating blade, similar to that of a rotary mower, provides the cutting action. These mowers are easy to push and manoeuvre around. More expensive versions also come with grass collection boxes. Adjusting cut-height can be difficult with this style of mower as you need to remove the blades then add/remove packing pieces.
This type of mower is unable to produce classic lawn stripes. However it can create a clean even finish without wheel marks and does not contribute to compaction of the soil surface.
Image Credit: Flymo Easi Glide 300 Electric Hover Collect Lawn Mower
These are a form of strimmer/mower combination tool, where a line trimmer is set into a wheeled deck assembly to ensure an even, level cut when used over the lawn. The strimmer unit can usually be removed from the deck and operated as a separate grass trimmer. These mowers are cheap and cheerful and don't give such a good clean cut, mainly because the rotating line tends to tear at the grass rather than cut through it cleanly. Although, it is a very useful low-cost option if you only have a small area to mow or need to maintain a wild area of garden.
Image Credit: BLACK+DECKER Strimmer with Lawn Mower Deck Attachment.
Mains/cordless garden tools have been available for sale for a few years now. These machines are able to use either mains or battery power. This provides the benefits of mains usage close to a power-outlet near the house and cable-free usage further away. Ideal if you have a very long garden or don't always have time to wait for the batteries to charge.
Note: For safety reasons, always use a Residual Circuit Breaker (RCB) when operating a mains powered lawn mower.
Image Credit: Ryobi
RLM18C34H25 ONE+ 36 V Cordless Hybrid Lawnmower.
Another recent innovation is the automated robot mower. Although more expensive, they can mow your lawn regularly, doing almost all the work for you, except for some edging areas that may need tidying up. Robot mowers can cope with most common lawn shapes and sizes. However, they are only suitable for light, regular cutting and can be tricky to set-up.
Image Credit: Husqvarna 105 automower
Ride-on mowers are very expensive items, with prices ranging from £1500 to £3000+. Plus you will need to include annual service costs and insurance to this. However, if you have a very large lawned area they will save you a considerable amount of time and effort. If you are considering purchasing a ride-on mower then it is best to seek guidance from a specialist dealer or agent. Who will provide advice on the type of mower suitable for your size of lawn.
Always take a test drive before making a final decision to ensure that it will do the job and that you feel comfortable operating it.
A range of specialised lawn care tools are also available to help keep a lawn looking good throughout the growing season. For details see our Lawn Care Products page.