You’ve faithfully trimmed your lawn from spring through fall, but how short should you cut grass before winter? We have the height recommendations you need to ace your final cut and some tips to make the last mows count.
Should grass be cut short for winter?
Winter grass height is one of the great debates on lawn care. Some insist you must mow low, others high, and some say not to change the height at all. So what’s the truth? Let’s go over the arguments made for each approach.
Reasons to mow your lawn shorter for winter
The most common advice is to mow low. However, it’s essential to know who recommends it and why.
Experts at Michigan State University recommend you mow cool-season grass one-half inch below your standard grass height for the last mow of the season. This slightly lower mowing height helps clean up the turf and plant debris. It also ensures the grass won’t be too tall if it’s not done growing.
Low mowing discourages pink snow mold and gray snow mold. As the name implies, these molds often appear in spring once the snow melts. Snow molds thrive in cold, wet, and matted lawns. Long grass encourages those conditions, whereas short grass reduces them. Snow molds are most common in cool-season grasses in the northern U.S.
Mowing low also discourages voles and other pests. These tiny creatures like to nest in taller grass, so a shorter cut discourages them from overwintering in your lawn.
Reasons to mow your lawn higher for winter
Experts at Clemson University recommend raising the height of warm-season grasses by one-half inch to prepare warm-season lawns for winter. Warm-season turfgrass is especially susceptible to cold damage because it’s best adapted for the warm southern U.S. Though it isn’t scientifically proven, the higher mowing height supposedly reduces warm-season turf winterkill.
A higher cut will allow the grass blades more leaf area for photosynthesis and may reduce winter injury. Increased height also helps grass (warm-season and cool-season) crowd out weeds and increase the lawn’s traffic tolerance — which is perfect if you sled down the lawn after winter snow.
Reasons to mow your lawn at the same height for winter
The Purdue Turfgrass Science Program advises homeowners not to mow lower at all. If your lawn doesn’t struggle with snow mold, pests, or winterkill, then you’re doing something right. There’s no need to fix something that isn’t broken, no matter what non-experts tell you.
If you’re stumped on which way to go, it’s a good idea to ask a local expert. Your local Cooperative Extension office is happy to give advice via phone or email.
Best grass height for winter
Generally, the best lawn height for winter is between 1 and 2 inches. However, it depends on the grass species.
Regardless of the type of grass, you should never cut off more than one-third of your grass’ height at a time, or you could damage your lawn and leave it even more susceptible to cold. If you want to lower or raise your mower height, do so gradually.
Best height for cool-season grass in winter
Below are the recommended mowing heights for cool-season grasses. You should mow cool-season lawns at their regular height or one-half inch shorter if they struggle with snow mold or pests. Mow them one-half inch taller if you have weed problems.
| Grass type | Ideal height in inches | Mow when the grass reaches this height |
| Tall fescue | 2-4 | 2.5-5.25 |
| Perennial ryegrass | 2-3 | 2.5-4 |
| Kentucky bluegrass | 2-3 | 2.5-4 |
| Fine fescue | 1.5-3 | 2-4 |
Best height for warm-season grass in winter
Below are the recommended heights for warm-season grass. Since warm-season grasses are more susceptible to winterkill, it’s best to keep them at their current height or mow them one-half inch higher for winter. This approach keeps the grass and soil insulated from the cold weather.
| Grass type | Ideal height in inches | Mow when the grass reaches this height |
| Bahiagrass | 3-4 | 4-5.5 |
| Bermudagrass | 1-2 | 1.25-2.5 |
| Buffalograss | 2-4 | 2.5-5.25 |
| Carpetgrass | 1-2 | 1.25-2.5 |
| Centipedegrass | 1.5-2 | 2-2.5 |
| St. Augustinegrass | 2.5-4 (2.5-3 for dwarf varieties and 3-4 for standard varieties) | 3.25-5.25 |
| Zoysiagrass | 1-2.5 | 1.25-3.25 |
When to stop mowing for the year
Don’t get ahead of yourself with the last cut of the year — keep mowing as long as your grass grows. Even as fall temps slow the top growth on your lawn, don’t stop. You’ll have to mow less frequently, but it’s essential to remove no more than one-third of the blade per mow. If you take off more than that, you’ll stress the grass too much.
To predict when your cool-season grass will stop growing, check your area’s first frost date. From there, you can work backward to gauge how many mows you have left so you can adjust your mowing height. Warm-season grasses have a different seasonal growth pattern and can go into dormancy once average soil and air temperatures drop below 50 to 55 degrees Fahrenheit.
Your grass may grow year-round if you live in a mild climate. In that case, you’ll need to mow throughout the winter.
How to winterize your lawn
Proper mowing isn’t the only thing you should do to prepare for cold weather. Here are some tips for winterizing your lawn:
- Mow the leaves: You can use fall leaves on your lawn as mulch to boost your lawn’s nutrients. A mulching mower is best for this job. A good rule of thumb is to mow when leaves cover less than 50% of the grass. Keep your lawn mower blades sharp, and use safety glasses and a dust mask for protection.
- Rake excess leaves and debris: Too many leaves can smother your grass and encourage diseases and pests. Bag extra leaves and use them to winterize your flower beds or to cover your garden soil.
- Adapt your irrigation routine: The winter months bring rain and snow, so your hose or sprinkler can take a break. Dormant grass also needs less water since it’s not actively growing. Don’t water when temperatures are below freezing.
- Apply pre-emergent herbicides: Some weeds germinate over winter and attack your lawn while it’s vulnerable. Use pre-emergent herbicides to stop them from appearing in the first place.
- Winterize your equipment: After you’re all done with your mower, leaf blowers, and string trimmers for the year, you need to winterize the equipment. To do this, empty the gas tanks, change the oil, remove batteries, complete repairs, and store them in a dry place. You also should winterize your sprinkler system so it doesn’t freeze.
FAQ about how short to cut grass before winter
Can you mow your grass in winter?
We don’t recommend it unless you live in a warm, subtropical climate. Dormant or frozen grass is very susceptible to damage, and the mower will leave unattractive tracks in the wet soil. If you need to mow your lawn in winter, wait for a dry, sunny day.
Will mowing leaves contribute to thatch buildup?
No, thatch buildup is caused by excessive fertilizer and insufficient beneficial microorganisms in the soil, among other things. Here are a few tips to make sure your leaf shredding efforts are a success:
- Mow the leaves often (once or twice per week)
- Mow over the leaves twice per session if needed
- If you have too many, use the extra chopped leaves in your compost pile, on flower beds, or in the garden
- Prevent thatch buildup throughout the growing season by following good management practices
Can I walk on frozen grass?
In short, walking on frozen turf is not a good idea. The turf is not in a season of active growth and cannot recover as it does during the growing season.
Bundle up and let a pro handle it
If your fall schedule doesn’t allow for such fine attention to detail in your lawn, contact one of our local lawn care professionals for a two-minute quote. They’ll mow grass and leaves and get your lawn through the fall and winter to come.
Main Photo Credit: Pixabay
