What height should you mow your lawn?
The rule of thumb when mowing your lawn…
A couple of weeks ago, while making another unloved lawn great again, we overheard a classic conversation between a father and teenage son that went like this:
Dad: Can you mow the lawn, son?
Son: Sure I can. What height should I cut it?
Dad: Oh, you know, not too low.
We’ve all been there. We’ve all been told not to cut the lawn too short. But have you ever been given an actual measurement? We thought not, and yet it’s one of the most frequently asked questions garden-people have. That’s why we are here to end the debate, remove the mystery, help chore-heavy teenagers everywhere earn some praise as well as their pocket money. We will explain just how much of the grass blade you should be removing when you mow the lawn. So let’s get to it:
There Is Only One Rule To Remember When Mowing
The next time you’re trying to work out exactly what “not too short” actually means, try and remember this lawn mowing rule of thumb: the optimal height for a cool-weather grass is around 2½ inches, and you should never cut more than a ⅓ off your grass blades in a single mowing session. As such, the best time to mow your lawn is when the grass has grown to around 3⅔ inches high. Easy.
Now we’re not expecting you to remember this rule all year around, or to stick to it 100% of the time because, well, we’re only humans. But we do recommend you try and keep to this rule in Spring and Autumn, while in the Summer months you err more on the side of caution (translation: let your grass grow a little longer and mow it a little higher).
Basically, set your mower deck a little higher when the weather hots up and drop it a little lower when the cooler months approach.
The Reason This Mowing Rule Is Important
Mowing is all about balance. On the one hand, you need to mow your grass in order to encourage good growth, as well as help make your lawn look healthier than Gwyneth Paltrow’s skin and more attractive than your old college crush. However, if you mow your grass too short (or as we call it: scalping), you are going to cause a great deal of stress to your grass plants, and that can cause long lasting damage.
So instead of creating a mowing schedule based purely on the length of time since you last mowed it, stop telling yourself that Saturday mornings are mowing time and start taking cues from the height of your grass. For example, by telling your teenager, “your chore’s include mowing the lawn every other week” you’re actually failing to acknowledge the growing conditions during that part of the season, such as rainfall or drought, both of which have a pretty big say on how much your lawn will grow.
The way we see it, mowing is actually a bit of an art form and one that requires little tweaks and adjustments throughout the year. For instance, let’s say you’re battling a bout of crabgrass, which will compete with your grass for space, it may be worth letting your grass grow a lush thick sward that allows it to crowd any weeds itself. The same goes for those warmer summer months, when letting your grass grow to 3 inches long will actually help it restore more water and nutrients, provide extra shade to the soil and inhibit any weeds from having a chance to grow. Then, once autumn comes around, you can go back to mowing at 2½ inches because the weather will have cooled off and your weeds will have been halted by frosts.
Easiest Way To Remember These Measurements
We might be wrong, but we’re guessing you don’t want to head into your garden with a tape measure to guess whether it’s time to mow your lawn or not. That’s where this little hack comes in: get a tape and draw a line across one of your lawn mower’s tyres 3⅔ inches from the ground with an arrow telling you which way is up and which way is down. By doing this, you simply have to wheel your mower out when you think it’s time to mow, see where the grass falls against your mark and take it from there.
As for the mowing itself, you simply have to get used to the adjustment settings on your mower, learn what slot gets you closest to the 2½ inches mowing height you want, marking that slot and then sharpening your mower blade for the cleanest and healthiest cuts.