How high do i mow my new lawn?

I took this photo while I was out mowing a lawn. The last time I was there, the new lawn on the left was just about due for its first cut.

This lawn is going to take a long time to recover from this cut

(if it ever does).

There are a few rules you need to follow if you want your new lawn to look good and be healthy.

When Should You Cut a New Lawn?

Wait until you see the start of a wave on your new lawn.
This will do a couple of things:

  • If you have sown a lawn from seed, it will allow the roots to take hold properly before you hit it with a mower.

  • If you have ready turf, it will have time to adjust to its new location and settle in before its first cut.


Once you see the signs of the grass starting to bend under its own weight, it is time to get the mower out.

Check Your Mower Before You Cut


Before you go ahead and cut the lawn, you need to check your mower.


Are your blades sharp?

If not, you will need to have them sharpened before going ahead.


A mower blade does not have to be as sharp as a steak knife, but it does need to have at least a bit of an edge to it.

  • If you have sown a lawn from seed, it will allow the roots to take hold properly before you hit it with a mower.

  • If you have sown a lawn from seed, it will allow the roots to take hold properly before you hit it with a mower.


If you cut your new lawn with a blunt blade, it will burse and damage the grass, this will make it susceptible to diseases.

The ⅓ Rule – Never Cut More Than a Third of the Grass Height


This doesn't just apply to grass. It is usually the case for any kind of plant, shrub, or even trees.


You need to cut your new lawn high for best results:

  • Cut it as high as your mower will go for the first cut.

  • Bring it down a bit more the following week.

Should You Catch or Mulch?


Catch and remove the grass if you are not using a dedicated mulch mower.

You do not want to leave clumps of grass on the lawn, as this can also cause diseases and an unhealthy lawn.

Mulching can be good for a lawn, and some of my best lawns are mulched, but I would not recommend doing it for your first cut.

What Happens If I Cut My Lawn Too Short?


The lawn on the left-hand side of this photo is going to face a few issues if they keep cutting it like this:

  • It will die off if it gets too hot as it does not have enough leaf cover.

  • The yellow pieces you see are sun damage due to lack of cover.

  • The brown patches you see are where the crown of the grass plant has been damaged. This could stunt or kill the grass plant completely.

  • It also leaves bare areas in the lawn that will be an ideal area for flat weeds to take root and infest the lawn.

What If I Don't Want to Do This Myself?

The answer here is simple if you live in Hamilton

.📞Just call us at Gecko Lawns, and we can take care of your new lawn for you.