How to mow a lawn

Discover how to mow a lawn for a luscious, healthy plot

How to mow a lawn
(Image credit: Unsplash/Daniel Watson)

It's late summer, and with the combination of hot and rainy weather we've been having, lawns will need frequent mowing. However, there is a right and wrong way to mow a lawn, and doing it the right way really pays off with a healthy, verdant lawn that will keep looking great into autumn. Read on to find out how to mow your lawn to perfection.

Check out our guide to the best lawnmowers that will help you do a great job.

1. How to mow a lawn? Follow the one third rule

When cutting your lawn for the first time in spring, always follow the one third rule: never cut more than a third of the blade of grass in one go, as cutting more than this can 'stress' the grass, stunting subsequent growth. Remember: grass isn't like any other plant, with fresh growth always at the bottom. 

Trim the grass gradually over a number of weeks to reach the desired length. Cutting the grass too short, too fast is known as ‘scalping’ which can lead to disease and weed infestation.

2. Unkempt lawn? It's still important to be patient

If your lawn is looking a bit wild and overgrown after the winter, resist the temptation to cut it all right down. Even if the overgrown grass looks lifeless, there will be tender growth underneath that may react negatively to an aggressive cut. Cut gradually over a number of weeks, gradually decreasing the cutting height on your lawnmower each time to reach your preferred grass length.

3. Take special care mowing new grass

Our top lawn care hacks

Use apple cider vinegar instead of weedkiller: it's just as effective and more eco-friendly.
Use garlic to deter root parasites: just spread garlic cloves over your lawn.
Wear stiletto shoes(!): the spiky heels will help puncture thick grass and let nutrients penetrate the soil.
Put rusty nails in your watering can: grass needs iron to photosynthesise, and the nails will release iron into the water.
Spray the lawn with an aspirin solution to prevent disease.

If you're regrowing patches of your lawn with brand new grass from seed, be especially careful not to damage this young grass. First-season grass from seed is especially tender, with weak blades that need time to establish. 

No new grass from seed should be cut before it reaches at least three inches in height. You can still mow the rest of your lawn, but you may wish to protect the fresh areas with temporary fencing. Yep, there is a common theme here – take it easy with that mower!

4. Hard-to-reach areas? Trim them with a cordless lawnmower

A good-looking lawn has well-defined borders; trimming the edge of a lawn is called 'contouring'. This can be tricky with traditional corded lawnmowers, but is much easier with cordless models, such as the Flymo Contour Cordless 20V.

Choose from the best electric lawnmowers, including cordless models, in our buyer's guide. 

5. Mow a lawn often in warm weather

Once the summer gets going, trim your lawn often – once or twice a week, depending on the desired length. Grass can grow literally overnight, so don't underestimate its potential to grow long quickly. Besides, not mowing your lawn will result in the grass going to seed. 

A lightweight, portable lawnmower is best for frequent mowing. We have the best compact, easy-to-use models in our buyer's guide to the best small garden lawnmowers. Bigger plot? 

6. Apply these basic mowing techniques

For best results, avoid always mowing your lawn in the same direction, as this can lead to compacted soil and ruts. Try to vary the mowing pattern and direction. Avoid mowing wet grass, as the result will be very uneven. Equally, don't mow your lawn during lunchtime heat; the best time to mow your lawn is mid-morning, when the grass is dry but not hot. 

7. Lawn edging

Sharp edges are crucial to neat and appealing lawn, but they can't achieved with a lawnmower alone. How to achieve perfect edges will depend on the general state of your lawn. If the edges are generally uneven, you may need to re-cut them with a half-moon edging iron or, if you don't have one, a sharp spade. Use a plank of wood or bricks to make sure you cut evenly. If you desire a curved effect, use a garden hose as your template. We advise re-cutting your lawn every year. 

Next, your edges will need regular trimming to keep them sharp. What you need here is a pair of sharp, long shears, although a hedge trimmer could also do the job – just make sure you pick a model that has a rotating head. 

Over-mowing: how to know if you're doing it

Over-mowing is a very common problem that leads to patchy, unhealthy lawns or the dreaded 'lawn burn' – a lawn that's turned brown seemingly for no reason. 

While mowing your lawn often in summer is important, if you mow too often, you're actually preventing the grass from photosynthethising, which is what makes it green, hence the brown, 'burnt' lawn. Our advice is: slow it down a little; that's what the different heights on your lawn mower blade are for. If you're mowing twice a week, and the weather's hot and dry, go down to once a week or even every other week. The same goes if your lawn is getting extra wear and tear this summer (whose isn't?).

Read more to prepare your garden for summer: