When learning how to mow the lawn the right way, start with these three rules: keep the mower blades sharp, never cut wet grass, and trim at the right height for your turf species.
They’re an excellent starting point for every lawn care beginner. But make no mistake, there’s more to mowing grass if you want a stunning lawn. We cover all the important mowing rules and tips in this article so you can start mowing your lawn like a pro.
Top benefits of mowing the grass correctly
You water and mow the lawn weekly, so these two actions significantly impact your lawn’s health. While watering is done automatically by your sprinkler system, mowing depends on your skills and knowledge. Here are the main benefits you can expect when you invest time to learn and apply the rules of proper mowing:
- You use less water: When mowed at the proper height, turfgrass develops deeper roots, is more resilient to drought, and requires less water during dry spells.
- You apply fewer pesticides and fungicides: Properly mowed grass is more resilient to pests and fungal diseases. It can fight off less extensive infestations on its own without your intervention.
- Herbicides are required less often. Good mowing practices create a dense, thick lawn that smothers weeds and controls them without weed killers.
- You need to make fewer lawn repairs: When you cut the turf correctly, it’s less exposed to developing bare patches.
- A beautiful yard year-round: Regular mowing keeps your lawn neat and lush throughout the growing season.
Investing just a few minutes a week to mow the lawn the right way keeps the grass healthy and strong and simplifies lawn maintenance drastically.
Regular lawn mowing is also an excellent opportunity to get outside and move your body. According to Harvard Health Publishing, 30 minutes of mowing helps you burn between 135 and 231 calories.
How to mow the lawn: Rules and tips
1. Only mow with sharp blades
“No matter what mowing equipment you use, be sure to have the blades sharpened every 10-12 hours of use,” advises Cornell College of Agriculture and Life Science (Cornell CALS). “Sharpened blades provide a clean cut and more attractive appearance. Dull blades leave ragged edges which contribute to disease occurrence and can increase fuel costs by 20%.”
How often should you sharpen the mower blades? One to three times a year is the average for residential lawns, but it depends on:
- The size of your lawn
- Climate
- Grass type
Large lawns, warmer and wetter climates where turf grows faster, and tougher grasses like Zoysia can run down mower blades faster and require more frequent sharpening.
How can you tell it is time to sharpen the blades? Common signs of dull mower blades include:
- Hairy tips (like thorn cloth) on freshly cut grass blades – instead of a smooth, cleanly sliced tip.
- Uneven grass at one pass of the mower.
- Clumps of grass pulled out from the ground.
- Tips of the grass turn whitish or brown a few days after mowing.
- Strange vibrations while mowing and feeling like the mower works slower than usual.
Check your mower blade. If you see small bends, nicks, and dents on its cutting edge, you need to sharpen it before going out again on the lawn.
What dulls your lawn mower blades? Debris, twigs, tree stumps, sandy or loose soil, stones, cement lawn decorations, and, over time, simply cutting the grass.
Who sharpens your mower blades? If you own a reel mower, you should have the blades sharpened by a professional. Rotary mower blades, on the other hand, can be sharpened DIY. Our guide, “How to sharpen lawn mower blades,” walks you through the entire process.
Professional sharpening services are available in home improvement stores and garden equipment shops. They cost as low as $10 per blade with the blade off and start at $15 if you go in with the blade still installed on the mower.
When should you replace the mower blades? A good rule of thumb is to replace them once a year. Signs that sharpening is no longer a solution include missing pieces, cracks, and substantial rust or bending.
2. Keep the proper mowing height
The correct mowing height for your lawn depends on your grass type. Check the table below to find out how high to set the mower blades for your turf type:
Grass species | Recommended mow height (inches) | Mow when it reaches this height (inches) |
Annual ryegrass | 1.5 – 2 | 2.25 – 3 |
Bermudagrass (seeded) | 1 – 1.5 | 1.5 – 2.25 |
Buffalograss | 1 – 2 | 1.5 – 3 |
Centipede grass | 2 | 3 |
Colonial bentgrass | 0.5 – 1 | 0.75 – 1.5 |
Creeping bentgrass | 0.5 inch or less | 0.75 inch or less |
Dichondra | 0.5 – 0.75 | 0.75 – 1.125 |
Hard fescue | 1.5 – 2.5 | 2.25 – 3.75 |
Hybrid Bermuda | 0.5 – 1 | 0.75 – 1.5 |
Kentucky bluegrass | 2-3 | 3-4.5 |
Kikuyugrass | 1 – 1.5 | 1.5 – 2.25 |
Perennial ryegrass | 1.5 – 2.5 | 2.25 – 3.75 |
Red fescue | 1.5 – 2.5 | 2.25 – 3.75 |
St. Augustinegrass | 2.5-3 | 3.75-4.5 |
Tall fescue | 1.5 – 3 | 2.5 – 4 |
Zoysiagrass | 0.5 – 1 | 0.75 – 1.5 |
Sources: University of California-Davis Integrated Pest Management program, University of Georgia-Augusta Richmond County Extension
What’s the one-third rule in mowing?
It’s a rule of thumb to guide your mowing routine and ensure healthy grass. The one-third rule says to cut only a maximum of one-third of the grass blade height each time you mow. It ensures regular mowing and reduces plant stress and water loss.
Cornell CALS recommends mowing the grass tall, toward the highest recommended mowing height, to promote deeper roots and more resilient turf. They also use the ⅓ rule to explain that taller grass reduces mowing frequency. Here are their estimates for different mowing heights:
Mowing height | Estimated mowing frequency (days) |
2 inches(Cutting 1 inch from grass that is 3 inches tall) | 5 days |
2.5 inches(Cutting 1.25 inches from grass that is 3.75 inches tall) | 6.3 days |
3 inches(Cutting 1.5 inches from grass that is 4.5 inches tall) | 7.5 days |
3.5 inches(Cutting 1.75 inches from grass that is 5.25 inches tall) | 8.8 days |
4 inches(Cutting 2 inches from grass that is 6 inches tall) | 10 days |
Source: Data adapted from the Cornell College of Agriculture and Science
What if you let the grass grow too tall? Simply mow gradually using the one-third rule until you reach the desired height.
Don’t scalp the lawn
Cutting too much of the grass height is called scalping and exposes the lawn to various health problems. Space for weeds to invade, faster evaporation, and fewer resources for grass plants to fight drought, pests, and disease are just a few to mention.
If in doubt or with an uneven lawn, it is always better to cut the grass a bit higher than risk scalping it.
Note: There are some exceptions. Scalping is sometimes used to force a faster exit from dormancy or prepare the site for overseeding in lawn renovations.
Should you adjust the mowing height by the season?
Allowing for taller turf during summer supports deeper root growth and increases the grass’s resilience to drought.
It’s a good practice for warm-season grasses or if you decide to irrigate and keep cool-season grass green during the hot season. Raising the mowing height is unnecessary if you allow winter turf to go dormant during summer.
Winter comes with different mowing requirements. “In areas with prolonged periods of snow cover where snow mold is a problem, the last mowing of the season should be 20 to 30 percent lower than normal to discourage fungal diseases in winter,” advises the Ohio State University Extension.
How do you change mowing height?
“If you want to change the mowing height, reduce it gradually (in .25 inch to .5 inch increments per week or mowings) to avoid removing excessive leaf area, scalping or weakening the turf,” advises Cornell CALS.
How do you check your mower’s height of cut (HOC)?
Most lawn mowers have levers (some riding mowers have knobs) that you use to set the cutting height. They come with letters or numbers that tell you what height corresponds to each setting. However, the labels don’t always match the indicated mowing heights, so it’s a good thing to check.
Here’s how you check the blade height for rotary mowers:
- Park your mower on a hard, leveled surface.
- Disconnect the spark plug.
- Set the mower blade at the lowest level.
- Insert a square wood block under the mowing deck, place it vertically on the ground, and press the blade on its surface.
- Take it out and measure how high the mower blade makes the sign.
- If it’s different from the height mentioned in the user manual or the label on the mower, write it down. This way, you won’t have to check it again.
- Repeat for all height levels.
This method works for both walk-behind and riding mowers.
Another way to do it is to mow a section of the lawn and measure the height of the grass afterward.
Note: If your mower has pneumatic tires, ensure the proper air pressure before checking the cutting height.
3. Know your lawn’s mowing season
Similar to lawn irrigation, timing the mowing is more about what your turf needs and how fast or slow it grows than about a fixed schedule. The typical mowing frequency is once a week but can change depending on various factors, such as the turf type.
When to mow cool-season grasses? Also known as winter grasses, they are grown commonly in the northern U.S. because of their cold tolerance. Their peak growing seasons are spring and fall. That’s when you need to spend more time mowing (you might need to mow twice a week).
Cool-season species go dormant during summer and slow their growth during winter, requiring less trimming during these two seasons.
Here are the general guidelines for mowing cool-season lawns:
Month | Mowing recommendations |
March | Mow to remove any excess old growth and create conditions for overseeding. |
April and May | Mow once or twice a week at the regular height for your grass species. |
June to August | Decrease the mowing frequency and increase mowing height by 1/2 to 1 inch if the grass stand is thin. |
September to November | Mow at regular height until the grass stops growing. |
When to mow warm-season grasses? As the name suggests, grass species such as Zoysia, Bermudagrass, and St. Augustine have their growth and mowing peaks during summer. Depending on where you live, they go dormant from mid-fall to late spring, requiring little to no mowing.
See general guidelines for mowing warm-season lawns below:
Month | Mowing recommendations |
March | Mow the grass once it starts growing tall enough. |
April and June | Mow once a week at the regular height for your grass species. |
July and August | Increase mowing height by 1/2 to 1 inch and mow as needed to keep this height. |
September and October | Mow at regular height until the turfgrass stops growing. |
Other factors that can require you to adjust the regular weekly mowing schedule are:
- Fertilizer applications: After you spread lawn fertilizer, turfgrass speeds up foliar growth due to the added nitrogen. You might need to increase the mowing frequency to keep it at the usual height.
- Warm and wet weather: Warm but not yet hot temperatures and generous rainfall promote faster grass growth. This typically happens from late spring to early summer or early fall, depending on where you live.
- Drought: Lack of water and high heat, on the other hand, are signs to reduce mowing frequency and allow the grass to grow taller. This promotes deeper roots, shades the soil, and improves drought tolerance. During dry spells, grass may not require mowing until active growth resumes after rainfall.
- Installing sod: Whether you patch bare spots or install a new lawn using sod, you should wait two to three weeks until it establishes proper roots before mowing.
- Overseeding: When overseeding an existing lawn, postpone mowing until the new grass is about 3 inches tall (two to four weeks).
- Installing a new lawn from seed: Newly seeded lawns should be mowed first when most of the seeded grass is 3 to 4 inches tall (4 to 6 inches tall). Younger plants can easily get caught in your mower’s wheels and uprooted.
4. The best time of day to mow the lawn
Mid-morning: Mow the lawn in the morning while it’s cool outside, but wait until the dew dries off the grass blades to avoid mowing a wet lawn. Typically, this means mowing between 8 a.m. and 10 a.m.
What about morning dew? If you see dew drops shining on your lawn, postpone the mowing for a few hours.
Early afternoon: The second option is to mow between 4 p.m. and 6 p.m. This avoids the scorching mid-day sun and allows the fresh blade cuts to close a few hours before nightfall.
The worst times to mow your lawn are:
- Mid-day, when the high heat is already stressing the grass.
- Late afternoon and evening. Blade cuts heal slower without sunlight, and grass plants are more vulnerable to fungal infections at night and early morning when dew sets in.
5. Don’t mow wet grass
It doesn’t matter if morning dew, rainfall, or your own sprinkler system is watering the lawn – mowing wet grass is a bad idea.
“It is harder to obtain a quality cut, clippings form clumps on the mower and turf, and disease organisms are more likely to be spread.” Julia Laughlin, a horticultural educator with the Oklahoma County Extension Office, explains.
The mix of leaf moisture and open cuts (easy to infect by fungal spores) makes for the ideal conditions for common foliar diseases such as dollar spot and brown patch.
6. Change your mowing pattern
Does it matter what direction you mow your lawn? Yes, it does. “If you always mow in the same direction, grass blades can develop a lean that results in spikes of uncut grass. Using the exact same pattern can also lead to ruts and compacted soil from mower wheel tracks.” says the Benton County Extension of Washington State University.
They recommend changing the pattern at each mowing session. Use the graph below to help you alternate the pattern.
Deal with the hard-to-mow places first.
That’s lawn edges and obstacles like trees, flower beds, or the tool shed.
Lawn edges require special attention and can make or wreak your turf’s appearance. So, start and end the mowing with them. Take the mower around the lawn and mow the edges first. This way, you’ll have a clean strip around the lawn to guide you when mowing the rest.
End the mowing session by driving a trimmer along the turf edge to get a clean line – read Lawn Love’s “How to edge a lawn guide” for all the details.
Use a line trimmer or an edger to approach grass around trees, curbs, flower beds, and other elements in your yard. You’ll have more precision and avoid damaging the lawn mower.
How to handle mower turns
Turning the mower on your lawn promotes soil compaction and leads to turf wear because of tire scuffing. New lawns are especially sensitive – grass is not yet properly rooted and can be pulled out. To limit damage, turn on walkways and driveways when possible and choose mowing patterns with fewer turns.
Why and how much should you overlap mowing strips? Overlapping is necessary to avoid spines of tall grass on your lawn. Benton County Extension of Washington State University suggests using a 4-inch overlap between two consecutive mowing paths for best results.
Sloped lawns are special
Mowing a sloped lawn can be challenging and dangerous if you don’t know how to approach it. Here are the basic rules to follow.
- Wear boots with good traction. Some homeowners use cleats to ensure better footing.
- Set the mower blades at a higher setting than for the flat areas. You won’t get a 100% even cut on a slope, and this way, you avoid scalping the grass. Experiment until you get the ideal height to make the entire lawn look even.
- Use a slower speed. It’s easier to control the mower.
- Avoid starting, turning, or stopping your mower on the slope. Find a more level area to use for turning the mower.
- Run a walk-behind mower from side to side. You are safer if slipping and have more control over mower movements. Drive the mowers horizontally across the slope or diagonally.
- Run riding mowers up and down the hill. It’s safer than mowing side to side for two reasons. First of all, the risk of rolling over is lower. Second, in case of sliding down the hill, you’re sliding in your mower’s driving direction and are more able to control it.
- Don’t use a riding mower on a slope steeper than 15 degrees. Instead, use a string trimmer, a push mower, or specialized equipment for steep slopes. Better yet, hire a professional to handle the difficult areas.
- Do not start, turn, or stop your mower on the slope. Find a more level area to do this.
Note: The no-wet-mowing rule is even more important when slope-mowing. Wet grass makes slipping and sliding down the lawn so much easier.
7. When to bag and when to mulch the grass clippings
“As long as the lawn is mowed on an as-needed basis and the one-third rule is followed, clippings will readily filter back down into the lawn, and need not to be collected.” says the University of Illinois Urbana-Champaign, Illinois Extension.
“The clippings readily decompose (they contain 75% – 80% water) and do not cause thatch. Clippings also recycle nutrients, in particular nitrogen, so less fertilizer is needed.” they add. Specifically, you can reduce fertilizer use by about 25% when you leave the grass clippings on the lawn.
However, there are some situations when mulching grass clippings can do more harm than good. For example, when:
- A turf fungus infects the grass
- The lawn becomes waterlogged, and the soil needs to dry faster
- You allow the grass to grow too tall, and clippings clump all over the lawn
Pro tip: If you like to grow your lawn taller but still want to mulch grass clippings, consider a mulching mower. Mulching mowers cut the grass clippings into fine pieces, even with tall grass, ensuring fast decomposition.
What’s the right mower for your lawn
The right lawn mower for your lawn’s size and shape and your mowing habits can make your lawn care tasks much easier. Here’s what factors to consider when choosing it.
Lawn size: The longer it takes to mow your lawn, the more likely you are to put it off. Choose a lawn model that makes it easy to care for your turf.
- Under ¼ acres (10,890 square feet), you can easily use a mower for small and medium yards, such as a reel mower, push mower, or self-propelled walk-behind mower.
- Between ¼ acres and 2 acres, consider a mower for big yards, such as a rear-engine riding mower, a residential-duty zero-turn mower, or a light-duty lawn tractor.
- Over 2 acres, you need a commercial-duty zero-turn mower.
Lawn design and topography:
- Level ground with obstacles (trees, stumps, etc.) – Choose a push or self-propelled mower with a front-wheel drive. It lets you control traction on the front wheels and better manage the mower in and out of corners.
- Uphill and sidehill mowing – Choose a mower with a rear-wheel drive. Its front tires won’t lose traction when going uphill.
- Steep uphill and downhill mowing and uneven terrain – Consider an all-wheel drive option.
Costs: Depending on the type, lawn mower prices vary from a few hundred to a few thousand dollars.
- Reel mowers cost $67 to $341.
- Push mowers can be bought for an average price of $115 to $1,021.
- Riding mowers are available at prices ranging from $1,287 to $4,510.
- Robot mowers cost between $630 to $17,021.
- Mulching mowers range between $130 and $2,198.
Fertilization strategy: If you plan to benefit from grass clippings and falling leaves as natural fertilizers, consider buying a mulching mower.
Lawn mowing safety tips
- Keep everybody away from the lawn while mowing (adults, children, pets).
- Remove any debris from the lawn. Stones and sticks can become dangerous projectiles and damage lawn mower blades.
- Read the user manual to ensure you’re using it correctly and safely.
- Wear protective equipment: safety glasses, ear plugs, sturdy shoes, and long-sleeved clothing.
- Delay mowing if the turf is wet. Wet grass is slippery.
- Always push the mower forward when cutting the grass. Pulling it back exposes you to the risk of slipping and getting your feet caught under the mower’s deck.
FAQ about lawn mowing
Why do landscapers mow diagonally?
If you mow repeatedly in the same direction, the mower wheels will cause parallel dents across your lawn’s surface. Mowing the lawn diagonally prevents the situation when all four mower wheels get into the dents simultaneously, bringing the blades low enough to scalp the lawn.
What is the most effective mowing pattern?
The most effective mowing pattern is the spiral: start from the outside and cut the lawn border first. Then, continue mowing, spiraling toward the middle.
How do I mow my lawn neatly?
To mow your lawn neatly and remove any rebellious grass blades, make a second pass over your lawn perpendicular to the initial one. Don’t use this technique too often on moist or clay soil, which is more prone to compaction.
Hire a pro to mow your lawn!
Mowing the turfgrass the right way is essential for a healthy lawn but also a weekly task that not all lawn owners love. If you’d rather spend that time with friends and family, hire a lawn care professional to mow the grass. With Lawn Love, you’ll find the right pro in a minute and enjoy your green, healthy lawn without lifting a finger!
Sources:
- Benton County Extension of Washington State University (2013, December). Lawn care calendar. https://s3.wp.wsu.edu/uploads/sites/2071/2013/12/Lawn-Care-Calendar.pdf
- Cornell College of Agriculture and Life Sciences (n.d.). Mowing. Sports Field Management – Maintaining Safe Sports Fields. https://safesportsfields.cals.cornell.edu/routine-care/mowing/
- Harvard Health Publishing (2021, March 8). Calories burned in 30 minutes for people of three different weights. Harvard Medical School. https://www.health.harvard.edu/diet-and-weight-loss/calories-burned-in-30-minutes-for-people-of-three-different-weights
- Martin, J.C., Eickholt, A., Dole, J. (2017, June 20). Natural Organic Lawn Care. Ohio State University Extension. https://ohioline.osu.edu/factsheet/hyg-4031
- Stotts, D. (2020, July 10). Adjust mowing frequency, cutting height on bermudagrass lawns. Oklahoma County Extension Office. https://news.okstate.edu/articles/agriculture/2020/stotts_bermudagrass-mowing.html
- University of Illinois Urbana-Champaign, Illinois Extension (n.d.). Mowing Your Lawn. https://extension.illinois.edu/lawns/mowing-your-lawn
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