What Happens If You Cut Grass Too Short (2022)

When you cut the grass too short, you make it vulnerable. Without enough of the leafy part, your grass will get scorched in the summertime. The grass will focus on restoring the blades instead of growing its root system. This in turn weakens the whole plant, leading to bald spots in the lawn.

Is your lawn in the worst shape it has ever been in? Don’t know what’s killing your grass? 

You might be cutting your grass too short! 

I can relate! I almost ruined my lawn with the same mistake. We are all lazy sometimes, and just want to cut our lawn short to get a break from mowing. But I figured, it takes more time, effort, and money to restore the lawn once the damage is done. 

Factors, such as climate and grass variety, can make your lawn more susceptible to damage if you cut it too short. I have come up with some great mowing tips for every type of yard there is. Check it out! 

Why Cutting Grass Too Short Is A Bad Idea

1. Just like any other leafy plant, your grass needs foliage to make food. Those seemingly unimportant green leaves support the process of photosynthesis. They absorb sunlight and carbon dioxide to aid the production of glucose. 

   Once you cut the leaves too short, you immediately impair photosynthesis. Without enough foliage, your grass can’t produce enough food for it to grow and thrive. 

2. Grass blades are not there just for looks. They serve a very important purpose, which is protecting the whole plant from heat. Without enough leaf blade growth, the grass will get scorched by the sun. 

3. Grass foliage also prevents fast evaporation of the water in the soil. If you keep your lawn a little taller, you won’t have to water it as frequently. That’s how I keep my watering bill low! 

4. When you cut your lawn too short, the grass puts a lot more energy towards growing its blades instead of its roots. When the root system is weak, the whole plant suffers. The lawn’s ability to absorb vital nutrients is impaired. In this case, the turf can’t grow thick and tall. 

   The easiest way to support deep root growth is to leave the grass blades taller and let the plant direct its energy toward root development. 

5. When you cut your lawn too short, you also make it more susceptible to diseases and insect infestations. When the plant is weakened from the root to the top, it cannot successfully fight off weeds and other invasive grass plants. 

I have minimized weeds in my yard by growing a healthy dense lawn that doesn’t spare weeds any space or nutrients. 

How Tall Should You Be Cutting Your Grass?  

How short you can mow your lawn without damaging it depends on the type of seed you are growing and the season you are in. Let’s take a look together. 

Best Mowing Height Based On Lawn Type 

Cool season grasses, like fescue and Kentucky Bluegrass, prefer 2.5 to 4-inch height. Warm season grasses, including zoysiagrass and Bermudagrass, favor 1 to 3-inch height. 

If this sounds too complicated remember that most grasses, regardless of the variety, like 2.5 to 3-inch length. To maintain the proper height from March to November, you will have to mow your lawn on a weekly basis. Learn how often you should mow your lawn and what time of day. 

Best Mowing Height Based On Season

I recommend you adapt the height of your lawn to the current season. Leave the grass closer to 3 inches in the spring to minimize the growth and spread of new weeds and crabgrass.  

From my personal experience, it is best to keep your lawn even longer in the summer to protect it from extreme heat. Mow it biweekly, and don’t be afraid to let the grass grow out to 4 inches in height. Your yard will look like a fluffy green carpet!

You can start trimming your grass short in the fall when the sun is milder and new weeds aren’t spreading anymore. With the lawn shorter, it is easier to facilitate end-of-the-year yard clean-up, as well!

Follow The 1/3 Rule  

You have probably heard people talking about the one-third rule when it comes to mowing. But what is this general rule?

The one-third rule means that you shouldn’t cut off more than one-third of the grass height at a time. If you cut more than a third off the top, you run the risk of damaging your turf. That’s why I recommend you read my guide on when to cut new grass for the first time. 

So, how does this rule work in practice? Well, if you like to keep your lawn 3 inches tall, like I do, you should let the grass grow out to about 4.5 before mowing it. 

Sometimes it is difficult to tell if the turf has reached the proper height for mowing. I have come up with a great solution for that! 

Make a 4.5 inch marking on the side of your push mower and compare it to the new growth before starting your lawn mower. 

Here’s how you cut tall grass to the recommended height. 

FAQs

Stay Consistent With Your Mowing 

You’ve made it to the end! Now you know why cutting your lawn too low is a bad idea. 

Most homeowners, myself included, sometimes take shortcuts to reduce chores. But when it comes to landscaping, it turns out these shortcuts only lead to more problems.

Achieving a healthy lawn is easier than you think. What you need to do is water deeply, fertilize the lawn properly, practice good mowing habits, and stay consistent. 
What do you think? Let me know in the comments below, and feel free to ask any questions. I would love to hear from you.