When it comes to mowing, height matters, but the “right” length isn’t the same for everyone.
Some people want a lush, easy-care lawn they can enjoy year-round. Others chase that perfectly striped, golf-green finish. Both can be right, it just depends on your goals, how much time you want to spend maintaining it, and the type of grass you have.
Let’s break it down so you can find your ideal mowing height.
The 1/3 Rule — A Key Pillar of Lawn Health
No matter your mowing style, this rule always applies:
Never remove more than one-third of the grass blade at once.
It’s a simple guideline that helps your lawn recover faster, grow deeper roots, and stay greener for longer. When you take off too much in one go, the grass diverts all its energy into repairing damage instead of building strength.
Think of it this way:
Aim to take a little less, not more. It might take an extra mow or two to get back to your preferred height, but it’s worth it — your lawn will look better and handle stress far more easily.
How to Tell If Your Lawn Is Too Short
A scalped lawn can’t photosynthesise properly, and it will start to show you it’s struggling. Look out for:
- Pale or yellow patches instead of rich green
- Soil visible between blades
- Weeds or moss creeping in
- Brittle, brown tips after mowing
- Thin or bare patches that don’t recover
If you can see dirt or the lawn feels uneven and sparse underfoot, your mower’s probably set a little low. Raise it a notch or two and give your lawn time to recover, it’ll thicken and deepen in colour surprisingly quickly once it’s not under stress.
What’s the Right Lawn Length for You?
Your ideal lawn height depends on how you use it, and how much time you want to spend maintaining it. Different grasses naturally suit different mowing heights, so finding that balance will keep your lawn healthy and easier to manage year-round.
For most homeowners (low-maintenance)
Best height: 25–40mm
Best suited for: Perennial Ryegrass or Fine and Tall Fescue lawns
This range balances appearance, comfort, and resilience. It stays greener for longer, tolerates dry spells, and doesn’t need mowing every few days.
- Perfect if you want a lush, soft lawn for kids or pets
- Mow every 7–10 days in spring, less in cooler months
- Feed with a slow-release or liquid fertiliser like LAWNZ Amplify or Soil Boost for steady growth
For enthusiasts and perfectionists
Best height: 15–25mm
Best suited for: Fine Fescue, Bentgrass, or Ryegrass lawns maintained to a high standard
A shorter cut gives that sharp, “pro” look — think golf greens and sports turf — but it needs consistent care and a strong maintenance routine.
- Only suitable for healthy, well-fed lawns with dense coverage
- Water deeply and more frequently, short lawns dry out faster
- Stick closely to the 1/3 rule and mow regularly
- Use a plant growth regulator like LAWNZ Density to slow vertical growth and encourage thicker turf
For busy or practical owners
Best height: 35–50mm
Best suited for: Tall Fescue, Ryegrass, or Kikuyu lawns
Longer grass shades the soil, conserves water, and hides small bumps or uneven patches, perfect for anyone wanting a lawn that stays green without constant attention.
- Ideal for warmer regions or properties with summer water restrictions
- Mow less often, roughly every 10–14 days
- Keep mower blades sharp to avoid tearing
- Raise the height even further in summer to protect from heat stress
Choosing the Right Lawn Length — All Year Round
Your ideal mowing height isn’t set in stone. As temperatures, daylight hours, and rainfall shift through the year, so do your lawn’s needs.
Cutting a little higher in summer helps shade the soil and retain moisture. Going slightly lower in cooler months improves airflow and reduces the risk of disease. The key is balance, and adjust gradually with the seasons to keep your lawn strong and healthy.
Tip: If you’re unsure, start at the higher end of your range and adjust down gradually — your lawn will always recover faster from being left a little long than from being cut too short.
Does Shorter Grass Grow Thicker?
Not automatically — it depends on how you mow.
Regular mowing encourages side shoots (called tillers), which make your lawn appear thicker. But cutting too short removes too much leaf, weakens the plant, and creates gaps for weeds to move in.
If you want thicker turf, focus on:
- Mowing regularly without scalping
- Feeding with nitrogen-rich fertiliser such as LAWNZ Enhance or Amplify
- Keeping blades sharp for a clean cut
- Using LAWNZ Density to slow vertical growth and encourage dense sideways spread
Quick tip: Mow little and often, it’s the most reliable way to get that dense, carpet-like finish.
When Not to Mow
There are times when mowing can do more harm than good. Hold off when:
- The lawn is wet or frosty — blades tear instead of cutting cleanly, increasing disease risk
- It’s hot and dry — grass is already stressed, and cutting will worsen browning
- You’ve just fertilised or sprayed — wait 24–48 hours to let products absorb properly
- Growth is slow or dormant — often mid-winter or mid-summer, depending on your region
Quick tip: If in doubt, take a step test, if footprints stay visible for more than an hour, your lawn’s under stress and not ready to mow.
What Happens If Grass Gets Too Long?
A slightly long lawn isn’t a problem, but if it’s left too long you’ll notice:
- Yellowing underneath where lower leaves are shaded
- Uneven or clumpy cuts after mowing
- Thick clippings that smother new shoots
- A soft, spongy feel underfoot
If this happens, don’t try to fix it in one go, follow the 1/3 rule and bring the height down gradually over two or three mows.
Quick tip: Raise the mower deck and cut again in a few days, patience beats scalping every time.
The Takeaway
There’s no single “perfect” height, it depends on your lawn type, lifestyle, and the season. But if you follow the 1/3 rule and adjust gently through the year, you’ll have a lawn that stays green, dense, and healthy all season long.