What's the Best Height to Mow my Lawn?

One of the biggest mistakes homeowners make is assuming that cutting the lawn shorter means they won't have to m

ow it as often.

It sounds logical—but in many cases, the opposite is true.

Cutting your lawn too short places unnecessary stress on the grass, leaving it more vulnerable to heat, drought, weeds and disease. While a freshly scalped lawn might stay shorter for a few extra days, it often takes longer to recover and can end up looking thinner, patchier and less healthy over time.

The goal isn't to cut your lawn as short as possible. It's to remove just enough growth to encourage healthy, consistent growth throughout the year.

Follow the One-Third Rule

As a general rule, never remove more than one-third of the grass blade in a single mow.

For example, if your lawn has grown to around 90 mm tall, you should aim to remove no more than 30 mm in one pass.

Removing too much at once forces the grass to recover from stress rather than putting its energy into healthy growth. That's one of the reasons regular lawn mowing usually produces a healthier lawn than waiting until it becomes overgrown.

Why Slightly Longer Grass Is Often Better

Many people are surprised to learn that a slightly longer lawn is usually a healthier lawn.

Longer grass blades provide more surface area for photosynthesis, helping the plant produce the energy it needs to develop stronger roots. They also shade the soil beneath the lawn, reducing moisture loss during warmer weather and making it harder for weeds to establish.

A lawn that's cut too short is exposed to more sunlight, dries out more quickly and often struggles during periods of heat or low rainfall.

The Best Mowing Height Changes Throughout the Year

There isn't one perfect mowing height for every season.

During spring, when growth is rapid, you can usually mow a little shorter while still following the one-third rule.

During summer, it's often better to leave your lawn slightly longer. The extra length helps shade the soil, retain moisture and protect the grass from heat stress.

As growth slows through autumn and winter, mowing becomes less frequent, but it's still important not to scalp the lawn before the colder months.

Different Lawns Grow Differently

Not all lawns should be treated the same.

The ideal mowing height depends on several factors, including:

• The grass variety.

• How much sun or shade the lawn receives.

• Recent rainfall.

• Soil moisture.

• How often the lawn is mown.

  
  

Rather than chasing a specific number, it's usually better to mow regularly and maintain a consistent height throughout the growing season.

So, What's the Best Height?

For most residential lawns in Launceston and Northern Tasmania, the healthiest approach is surprisingly simple:

• Avoid cutting the lawn too short.

• Follow the one-third rule whenever possible.

• Leave the grass slightly longer during hot, dry weather.

• Adjust your mowing frequency with the seasons rather than trying to remove large amounts of growth in one visit.

  
  

A healthy lawn isn't created by one perfect mow—it's the result of regular maintenance, good timing and avoiding unnecessary stress on the grass.

Common Lawn Mowing Mistakes to Avoid

Cutting the Grass Too Short

It might seem like mowing your lawn shorter means you won't have to mow it as often, but scalping your lawn can weaken the grass, expose the soil to heat and encourage weeds to grow.

Waiting Too Long Between Mows

Letting your lawn become overgrown before mowing often means removing too much of the grass at once. This places unnecessary stress on the lawn and leaves large clumps of clippings behind.

Mowing Wet Grass

Wet grass doesn't cut cleanly. It can clog your mower, leave uneven patches, damage the lawn and create muddy ruts—especially on softer ground.

Using Blunt Mower Blades

Sharp blades make a clean cut. Blunt blades tear the grass instead, leaving ragged edges that can turn brown and make the lawn more susceptible to disease.

Mowing the Same Pattern Every Time

Repeatedly mowing in the same direction can cause grass to lean over and develop visible wheel tracks. Alternating your mowing pattern helps the lawn stand upright and creates a more even finish.

Removing Too Much at Once

A good rule of thumb is to never remove more than one-third of the grass blade in a single mow. Removing too much too quickly puts unnecessary stress on the lawn and slows healthy growth.

Ignoring the Weather

Grass grows at different rates throughout the year. Mowing schedules should change with the seasons, rainfall and temperature rather than sticking to the same routine every month.

Using the Wrong Mower Height for the Season

Many homeowners leave their mower set to the same height all year round. During summer, allowing your grass to grow slightly longer helps shade the soil and retain moisture, while spring often allows for more frequent mowing. Adjusting your mowing height with the seasons is one of the easiest ways to keep your lawn healthier without any extra work.

🌱 Rule of Thumb

Never remove more than one-third of your lawn's height in a single mow. Regular mowing is healthier than cutting it short and hoping it lasts longer.