How we test lawnmowers and grass trimmers

All lawnmowers undergo the identical tests enabling us to gauge their performance, cutting ability and battery life.

For lawncare products, we put all of the products we have through the same tests, so that we can measure how good each product is, and let you compare the differences. 

This article covers both lawnmowers and grass trimmers, as they need similar tests.

Cutting performance

Lawnmowers are plugged in or set up with a full battery, and then we mow three test strips on medium-length grass. We use three heights: high/medium, medium/low and low. We take before and after photos and examine the overall cut finish on each strip, looking at blades of grass to see if there’s a nice sharp cut or a ragged finish.

We look for missed areas and whether the blade has cut the full width. And, we look to see if there are wheel marks or a neat roller finish.

Mowing general surfaces: we perform general mowing on normal, flat lawn, and test how easy it is to move the mower in a straight line and for tilt-turns.

Mixed terrain mowing: we test rougher area of the grass (usually our paddock and down to pond). We mow on 25% gradient banks – taken crossways – and asses if each machine is good to use on steep slopes and any issues with usability

Lumps and bumpy surfaces: we test to see if mowers go over easily and if they scalp highs areas or not. If a mower scalps we see if the motor slows.

Undergrowth: (long grass and brambles) we see if a mower copes or stops and if the motor slows.

Grass trimmers are put on full charge, and then we perform a cut on regular and tall grass, taking before and after photos to show the quality of cut.

We then test trimmers on long grass and brambles to see how well they cope with thicker material.

Ease of use

We examine if all of the grass goes into the collecting bin of a lawnmower or if some is left behind. And, if there’s a bag full indicator, does it work? With a full bin, we test how easy it is to empty the grass cuttings and refit the bin.

We measure the size of a load of a full bin on litres and takes notes on compression (some mowers compress the cut grass better than others, so you get more in).

We measure how easy a mower and grass trimmer is to clean after use, and if the wheels and blades or line is easily accessible for user-service.

Finally, we see if the products is easy to store and lift into storage.

Battery life and batteries

For rechargeable models, we note the time to charge from flat, and make notes on any interesting features or pack cooling.

After charging, we let batteries cool to ensure maximum capacity. We test run-time test on flat lawn, with the mower set to a medium cut height on a 30m long area in straight strips doing 180deg tilt turns at the ends. Full run time of the battery is measured by a stopwatch, paused for unloading grass collector, and other maintenance.

We recharge and repeat runtime tests with any battery save or Eco modes.

Scoring and verdict

After all the tests are complete, we score the product using the criteria mentioned here. We first check to see if the product’s performance matches the manufacturer’s claims, and that all the features work as expected and advertised.