What if I told you that mowing a lawn properly will save water, save money, dramatically reduce weeds, bring out the dark green color, improve the soil health, take less time, and prevent fungus problems… would you make the necessary changes? Mowing a lawn correctly is so easy and so important, yet so many homeowners and professional lawn care companies make these 3 easily avoidable mistakes.

#1 Mowing the Lawn Too Short!

Turfgrasses thrive when they are mowed at 3 inches or taller. Yet, most lawns are being mowed somewhere between 2 inches and 3 inches. Perhaps this mentality is due to an association with golf courses, which mow the turf so short, but we don’t play golf on our lawns. So, let’s see why mowing the lawn too short is so damaging. The biggest issue with mowing short is that grass roots will only grow at a maximum of 3 times as deep as the grass is cut tall. Therefore, if a lawn is cut at 2 inches tall, the maximum the grass roots can grow is 6 inches deep. If a lawn is cut at 3 inches tall, the grass roots can grow about 9 inches deep. That is a huge improvement! Deep-digging roots are extremely important to the health of a lawn because a lawn with well-established roots will be able to easily transition from cool, wet weather in the spring to hot, dry weather in the summer. A lawn with deep-digging roots that are 8-9 inches deep will also be able to stay green with about 33% less water than a lawn with 5-6 inch deep roots. Everyone knows that deep-digging roots are better than shallow roots! So what are some other mistakes that we see when mowing a lawn?

#2 Mowing the Grass Too Short!

Wait, that sounds a lot like #1! Yep, this is exactly like mowing the lawn too short. Why did we say it again? Probably because more than 50% of all lawns are being mowed too short and I probably have this conversation every time one of our lawn care technicians or I go to look at a problem lawn. The conversation goes something like this… Organo-Lawn Brad: “Hi there, did you know your lawn is being mowed too short and by raising your lawn mower height your lawn will have fewer weeds, use less water and have a deeper darker green color?” Customer: “That is helpful, but I am mowing the lawn at 3 inches.” Organo-Lawn Brad: “Hmmm let me measure it with a ruler… as you can see it is being cut at 2 inches. We strongly recommend that you cut the lawn at the highest setting on the lawn mower.” Customer: “That is strange; I have it on the highest setting.” Organo-Lawn Brad: “Can I take a look at your lawn mower?” Customer: “Sure, it is in my garage, there it is right there.” Organo-Lawn Brad: “Yep, that is what I thought! As you can see, it is on the middle setting. I think this happens a lot because people think the highest setting must be too tall and the lowest setting must be too low; so they put it on the middle. In actuality the middle setting is too low and the highest setting is the correct choice.” Customer: “Look, it is on setting 3 on the lawn mower, doesn’t that mean it is on 3 inches?” Organo-Lawn Brad: “Those numbers on the lawn mower mean nothing, they are just numbers. The best setting is to put it on the highest setting and leave it!” Customer: “That is strange; I had it on the highest setting. My son must have moved it when he mowed the lawn.” Organo-Lawn Brad: “That is probably what happened; your son must have moved it!”

#3 Mowing the Turf Too Short

That sounds a lot like #1 and #2! Because it is! Mowing the lawn too short causes so much damage and it is the most common mistake that is also the easiest change that a homeowner can make! The small change of raising the lawn mower height from 2 inches to 3 inches will bring out the full green color of the grass. Instead of a lime-green color, the grass will be a deep dark emerald-green color. Grass stores water in its blades and by removing less of the blade of grass the lawn will have more water stored. The better water content a lawn has in each blade of grass, the darker green the grass will be and the healthier it will look.

Mowing the Grass Tall Will Transform the Lawn

1. The grass roots will dig deeper into the soil. Deep-digging roots will mean a more drought-tolerant lawn, and will require about 33% less water than a lawn with shallow roots. The lawn will require about 33% less water because it has deep digging roots and because the grass stores water in the blade of grass. When there is more grass blade preserved, there will be less water required to restore the water content of the turf.
2. Mowing the lawn will take less time and it will be easier on whoever is mowing the lawn. If you don’t believe me try this experiment. Let the grass grow to 3 inches tall, then mow the lawn down to 2 inches. Time how long it takes… Now let the lawn grow to 4 inches tall and mow it down to 3 inches in height. I bet you will find it significantly faster and much easier when mowing at 3 inches tall vs 2 inches tall!
3. The lawn will have fewer weeds! A lawn that is mowed at 3 inches tall will have about 40% fewer weeds than a lawn that is mowed at 2 inches. This is because the grass will not have to repair the blades and instead it can use its energy to spread out via rhizomes. These are roots that dig sideways and have the ability to develop new shoots of grass. These roots help fill in thin areas, but grasses only spread via rhizomes if they are healthy. When a lawn is mowed too short the grass uses its energy to repair itself instead of spread out.
4. The soil will be healthier! Mowing the lawn taller will make the soil healthier? Yes! The reason for this is because roots not only take; they also give. Roots give off sugars and these sugars attract beneficial bacteria. These bacteria are the most basic microorganism and are the foundation to a “living soil.” The more beneficial bacteria and beneficial microbes the soil has thriving in the soil, the healthier the soil will become. The foundation of a living soil is deep-digging roots and the deeper the roots dig the deeper the microbial bed will be.
5. The lawn will have fewer diseases! Lawn diseases are typically caused by improper lawn watering practices. The most severe lawn diseases like necrotic ring spot and fairy ring are caused by over watering. If the grass is mowed taller the lawn will require less water to stay green and the less a lawn is watered the less likely it is to develop a disease.

If you are mowing your grass short, blame your son and then raise your lawn mower deck! If your lawn mowing company is mowing the grass short, ask them to raise the lawn mower deck. If they say they can’t, find a new company! Mowing the lawn at 3 inches or taller is the easiest change that makes the biggest impact on the health of a lawn.