When to Mow New Grass From Seed

By Brian Mounts | May 26, 2021
when to mow new grass from seed

After you’re done seeding your lawn, new grass might take a while to show up. At the beginning, it might even appear to be too little and too unevenly distributed. But if everything goes well, you’ll soon have a lush green lawn with a lot of grass growing really quickly!

And that’s when you know it’s time to mow your lawn, right? Well, as it turns out, not always. It just so happens that the grass is still in a basic phase of growth and you want to be a little careful. You need to know when and how you might want to mow your lawn at this stage.

Doing it properly is going to ensure the safety as well as the overall health of your grass. We know you’re working for the lawn of your dreams, and you don’t want all your efforts to go to waste. So, you need to be a little more discreet when it comes to mowing it this time.

So, when to mow new grass from seed? That’s exactly what we are going to take a look at in today’s article here at Turf Mechanic. We are going to find out the basic things you need to keep in mind when mowing new grass from seed, and when you might want to mow it. So, are you ready to get started?

Some basics facts to keep in mind.

Now, there are some basics that you need to keep in mind before you jump into mowing. There are several things that the ideal time to mow your new grass depends on. While there are quite a few factors that actually play a role, here are the top few ones- you really must consider at least these:

  • Type of Grass: The type of grass is one of the main things you might want to keep in mind. This is so because the right time to mow a grass varies from one grass to another. As such, you need to be really careful about which grass you’re using and what’s the right time to do it for your grass.
  • Time of the year: The time of the year is also another major thing that plays a role. If your garden gets slightly flooded during the rains, or gets snow during the winters, then those naturally aren’t the best times to do it.
  • How big you need the grass to be before you cut it: Well, you just cannot the grass whenever you feel like it’s getting large. At this stage, the grass’ root network isn’t sufficiently developed and carelessness can easily kill your grass. So, experts recommend waiting until the grass is somewhere between 3-4 inches before you go for it. By this time, the grass usually develops a better root network, and it actually does start to get a little big.
  • Specific techniques: One more thing you might want to keep in mind at this stage is that some people recommend some specific techniques. For example, some people recommend actually drying your grass up a bit so that you can cut of the edges cleanly without actually getting them stuck, which would result in the grass getting uprooted. Quoting SFGATE,

After allowing your grass to grow 3 inches high, but no taller than 4 inches, you must stop all irrigation for at least 48 hours. Drying the grass blades provides a healthy environment for clean cuts as the mower moves across the turf – wet grass becomes tangled and torn during mowing. As you mow the lawn, only remove up to one-third of the grass blade length at a time with sharpened mower blades. If the grass is still too long, mow it in a different direction the next day. Removing one-third of the grass height at a time reduces stress and provides adequate surface area for continued photosynthesis.

When to mow new grass from seed?

Now, let’s address the actual question that we’ve been waiting for till now. Well, it just so happens that this question cannot be answered in terms of time in a perfectly generalized way. Let me explain why under the following headings:

  • Depends on the grass type: This honestly depends on the exact grass type that we’re talking of. With some grass types, this stage can come up in about as early as a week! While some other grass types might take up to even a month or more. So, this cannot really be addressed in terms of time.
  • Geographical conditions: Another major thing that determines how fast your grass grows is the geographical condition. Naturally, if it is favorable, it’s going to grow substantially faster, and vice versa. So, that’s yet another unpredictable thing that makes a general answer pretty much impossible. In case your lawn does not get enough water, please consider getting a good sprinkler. Click here to check out our recommended Top 4 Impact Sprinklers on Tripod!
  • Your wishes: Again, it’s your grass and you might want to have it a little larger. Only you can know how big you want your grass to ideally be, and that’s something that makes generalization impossible too. Even if we were to assume a specific rate of growth, it would still be impossible to tell you exactly when to mow the lawn in terms of time.

But, you can answer it in another way!

But, you can pretty much answer it in another way- the height for your grass at which you might want to cut it. Well, while it also depends on the specific type of grass in question, generalization is much simpler here.

Naturally, you might still want to have your grass a little larger, and that’s entirely your choice, but this is just a generalized answer about what time it is usually right to cut it according to the experts.

Well, it just so happens that experts recommend mowing your new grass from seed when it reaches a height somewhere between 3-4 inches. As I remarked earlier in the article, a height less than 3 inches might still have the grass at a stage of infancy and can be potentially damaging. Again, after 4 inches, it might be a little harder to mow it properly. So, this range is usually treated by the experts as an ideal range.

Quoting BackyardBoss,

A lawn kept right around 3 inches following the ⅓ rule is the perfect height to ensure healthy new growth before cutting again, as well as the added benefit of crowding out unwanted weeds. Since roots anchor your seedlings into place, if you mow too early you can rip your new growth right out of the ground, negating all the weeks of watering and anxious waiting for green to appear.

For new grass you want to be sure the grass has reached at least 3 ½ inches in height, if not more, before cutting for the first time. This should take about 8 weeks, so be patient! When you are able to cut for the first time, you will want to make sure you follow good cutting techniques and mow high.

See my full grass growing guide here for more helpful tips – no opt-in needed.

Keep in mind: Have sharp lawn-mower blades!

One thing you might want to keep in mind is that your lawnmower needs to have sharp blades when doing this job. As we remarked earlier, the grass still isn’t really old, and too much force might actually still uproot them.

Naturally, if your lawn mower doesn’t have sharp blades, a few grass getting uprooted is something that you might find happening every once in a while, making the whole job really messy as well as causing a lot of damage to your new turf.

So, you might want to take a little precaution to actually avoid it altogether. We recommend that you ensure that your lawn mower has sharp blades, because that would actually make it a lot easier to properly cut the grass instead of unevenly pulling them.

Now, keep in mind to water your plants!

Watering your plants properly is really important. You might be wondering if you can overwater your seed, but it turns out you can, as you can find out in our article here!

So, it is important that you water your seeds properly. Now, sprinklers are a great choice to actually make the job easier for you. However, turns out there are quite a few types of those available out there. And each of these types has so many models that it’s hard to choose! So, here are a few that you might want to check out from each category to water your plants:

Impact Sprinklers:  Top 4 Impact Sprinklers on Tripod!

Oscillating Sprinklers: Top 4 Oscillating Sprinklers with Built-in Timers!

Also, wind can be a really important thing to keep in mind when it comes to adjusting your sprinklers. So, you might want to search for choices that are better suited for windy areas. Naturally, it isn’t too easy to find one of those- but we here at Turf Mechanic have got your back!

Click here to find out the Best Sprinklers for Windy Areas!


You’ve finally made it to the end of today’s article! In today’s article, we talked about when to mow new grass from seed. We discussed the main things you might want to know before you actually do the mowing. Then, we also discussed how and when you might want to actually move on to the mowing.

We also discussed about how you need to water your plants timely. After all, you need to take care of your turf in order to get the lawn that you dream of! As lawn owners ourselves, we here at Turf Mechanic understand your vision and we try our best to help you out! We understand that you might still have a few questions for us, and we encourage you to reach out to us with any that you might have, because we’d love to try our best to help you out!

Finally, we would like to thank you for taking your time to read this article till the very end. We really hope that you’d stick around to read our upcoming articles as well! Until we meet again on another article, we request you to take care and wish you a great day!