You can mow grass after the first frost as long as the grass has had a chance to thaw and dry completely. Before mowing, make sure there are no freezing temperatures forecast for the next 3 days. Even the most winter-hardy grass can be damaged by cold weather arriving too soon after mowing. Since it is risky to mow after freezing temperatures have begun, it’s a good idea to create a fall mowing schedule for future years.
Does it Hurt Your Grass to Mow it After Frost?
Mowing grass that is still covered in frost can be extremely harmful to your lawn. Additionally, mowing a lawn that is still wet from melted frost can hurt your grass. In both cases, the grass blades will be torn and damaged. Mowing too soon after frost can even kill some of your grass.
- Never mow grass that still has visible frost on the blades.
- Do not mow grass that is wet from melted frost.
- Mowing too soon after frost can cause serious harm to any type of grass.
- If conditions are right, you can safely mow after a frosty night.
If temperatures have risen substantially after frost and the lawn is dry and ice-free, you can still mow safely. So, if you don’t want to have a shaggy lawn all winter, there’s still hope. Just follow a few precautions to preserve the health of your lawn during the colder months.
5 Tips to Safely Mow Grass After the First Frost
Frosty weather can sneak up on us. If frost has arrived earlier than expected, you don’t have to put your lawn mower away for the winter. Just follow these precautions to safely mow your yard. This way, you’ll have a neat yard throughout the winter months.
Wait Until the Frost Thaws
If you want to mow after frost, wait until there are no more icy patches on your lawn. Don’t panic if frost arrives before your last planned mowing of the season. The worst thing you can do is mow frosty, frozen grass. Frosty grass is brittle, and mowing while there is still frost on the blades can cause severe damage. It can even kill the grass plants, resulting in dead spots in your lawn.
Make Sure the Grass is Dry
Wait for the grass to completely dry out before you fire up your mower. When frost melts, it can leave grass damp and dewy. Mowing wet grass can be just as damaging as mowing when the grass is still frost-covered. Wet grass is not cleanly cut by your mower. Instead, the grass blades will be shredded. This can open the door for snow mold and other fungal diseases.
Check the Forecast
If a frost has recently occurred, check the upcoming weather before you mow. If there are nighttime temperatures at or below 32℉ (0℃) within the next 3 days, do not mow. Frost can damage fresh-cut grass. Grass needs a chance to recover after mowing, so it can resist disease. Ideally, temperatures should be above 40℉ (4℃) for 3 consecutive days after mowing to allow your grass to heal and protect itself.
Protect Your Yard from Frost
If more freezing weather is in the forecast, you can help prevent frost from covering your grass blades by watering. It may sound strange to water before freezing temperatures arrive, but watering insulates the ground and prevents frost from taking hold. Our guide to protecting new grass from frost will prevent your freshly mowed lawn from being attacked by frost.
Plan for Next Winter
Instead of being surprised by frost, it’s best to plan to mow for the last time in 1–2 weeks before the first average fall frost. This online tool can give the frost dates for your region. Since even cool-season grasses completely stop their growth by the time temperatures consistently drop to 40℉ (4℃), there’s no need to wait until frost arrives to give your lawn a final trim.
When Should You Not Mow Your Lawn?
You should never mow your lawn when temperatures are below 40℉ (4℃). So, if you’re considering cutting your grass when it’s cold outside, put a pause on your plans. Grass that is frosty, icy, or snowy will often be killed by mowing. Mowing leaves an open wound at the end of each grass blade. If the grass isn’t growing because cold weather has forced it into dormancy, it cannot recover from this wound. This makes it very easy for diseases to attack and kill your grass.
- Any time your grass is dormant.
- When nighttime lows are below 40℉ (4℃).
- If there is frost, ice, or snow on your lawn.
- If your grass is wet.
Tailor your mowing habits to your grass type. Most warm-season grasses begin to enter dormancy when temperatures drop below 65℉ (18℃), so they cannot recover from mowing in temperatures below this point. Even the most winter-hardy grass slows or stops its growth once temperatures drop to 40℉ (4℃). So, it is essential to mow in warmer weather.
Is it Better to Leave Your Lawn Long or Short for Winter?
It is best to cut your grass to a tidy height before winter sets in, rather than leave it long. Cut it to the standard height for your grass type, which is typically 2–3 inches (5–7.5 cm). Not only will shorter grass look neater in winter, but it can also have other benefits. Long grass left over winter can harbor rodents, especially if it snows in your region.
- It’s best to mow your lawn to a grass height of 2–3 inches (5–7.5 cm) before winter begins.
- Short grass discourages rodents from invading your lawn in winter.
- You will have better results dormant seeding if you mow your lawn short for winter.
Mowing your grass short before winter can have other pluses. If you would like to try dormant seeding your lawn to encourage thicker grass in spring, short grass encourages better seed-to-soil contact. Overall, it’s better to mow your lawn short before the winter months begin. Then, resume mowing in spring.
Should You Mow Your Lawn After the First Frost?
When considering whether or not to mow your lawn after the first frost of fall, keep these tips in mind. They will save your lawn from damage and dead spots.
- Do not mow while there is still frost on the grass.
- Never mow while your grass is still wet from melted frost.
- Only mow if there are no freezing temperatures in the forecast for the next 3 days.
- If you want to mow, consider watering your lawn before frost—this can prevent your grass from freezing.
- In the future, plan your final yearly mowing run 1–2 weeks before the first average fall frost.
By taking a few precautions, you can safely mow your yard even if frosty weather has arrived. Just wait for the right lawn conditions and a warm spell. Then, you can cut back that long grass before winter sets in.