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Mowing Frozen Grass, this is what you need to do

Having a lush, healthy, and aesthetically appealing lawn is a dream of every owner. An eye-catching lawn always adds to the house’s beauty and is satisfactory for the people living around it. However, maintaining a beautiful lawn requires some effort and care. Every lawn has to go through different weather conditions throughout the year. Preparing your lawn for more challenging conditions to survive during those times requires extra care from the owner. In the autumn, you have those days where the night is so cold that the grass will freeze, but the days still see nice temperatures. This is a harder time for lawns. The Frost in the winter freezes the water inside the grass’s blades, and any step on the grass can damage its blades.  

Mowing Frozen Grass, this is what you need to do:

Mowing frozen grass is harmful to your lawn and can damage it. The grass cannot bear any physical stress during those conditions. Mowing frozen or frosted grass causes excessive rupturing of the cells in the plant. Please wait for the grass to defrost before you start mowing it. Mowing in frosty conditions requires extra patience and care so that you keep your lawn neat without causing any serious damage to the grass.

This article will also give you information about mowing your grass in the autumn and early winter when the nights are getting colder. It will discuss the necessary measures that must be taken and important techniques regarding mowing timing and mowing height that should be used to prepare your lawn for more challenging conditions.

Effects of Frost on the grass

In regions with cool-season turf, grass grows readily and quickly in fall. The cooler air and autumnal rains give the lawn a boost and send them into a rapid growth phase. However, following a few hard touches of Frost, warm-season grasses go dormant. You can cause serious damage to the grass in your lawn during this time if you walk across it.

So, let’s discuss how Frost impacts your lawn so that you can be aware of the damage caused to it. During cold and clear nights, Frost occurs when the atmospheric conditions cause the grass to become colder than the surrounding air. Frost can be light or heavy, depending upon the surrounding conditions. It can kill the annual plants and cause the perennial plants to go dormant.

Grass leaves contain water for their nourishment. Frost freezes this water inside the grass leaves, and during this freezing process, the water molecules naturally expand. This expansion of the water molecules damages the cell and ruptures the cell walls. Light Frost doesn’t freeze the ground, so the grassroots are still above the freezing point even if the grass’s blades are frozen. As a result, the grass blades damaged by light Frost will be healed by the roots as the grass continues to grow.

However, heavy Frost over several nights can lead to visible signs of damage. The extent of damage caused by the Frost depends upon the type of grass. For example, St. Augustine grass develops a brown, yellow, or purple hue when the Frost damages it. Bermuda grass also develops a brown, patchy appearance and dies relatively quickly if the warm temperature doesn’t return.

A frosted lawn requires extra care as the grass blades are frozen during this period. In general, the grass is tough and, in most circumstances, is not damaged by the Frost. However, the damage will most certainly occur if it is walked on or mowed while still frozen. Any traffic or activity such as walking on it or mowing it can break the grass blades.

The expanded water molecules inside the frozen grass blades slice through the grass and cause significant damage to the cells when a heavy object presses on these frozen blades. Most of the exposed areas near the top of the plant will turn white and begin to curl.  In more extreme cases, you may be seeing some browning and discoloration lower on the plant leaves. After this damage, the lawn might recover eventually, but it might not bounce back fully until the spring. 

Mowing during late fall and early winter

We are all aware of seeing Frost on the lawns in the late fall or winter mornings. Frost is frozen droplets of dew that have frozen overnight on the cold surface. Winter is always a taxing time for lawn care. Walking and mowing should be given careful considerations during this time of the year, as it can damage the grass during Frost. The Frost freezes the grass blades, and whenever an object presses on these frozen grass blades, they get damaged. So, taking out your mower on a frosty cold morning to mow your lawn is never a good idea.

When the Frost has gone into the ground, this means that the moisture in the root is freezing. Try to avoid mowing at this time where the frozen root zone meets the non-frozen soil. Any pressure on the soil at this stage will create a shearing effect, and the two layers will be moving left and right against each other.

This causes a root break where the deeper roots get broken off when the upper frozen roots surface slides over it. Mowing when the grass is cold and brittle may damage or even crush the grass’s crown, which is the area near the base of the grass blade where the grass sprouts. By destroying the grass crown, you may destroy any possibility of growth later in the spring.

If you want to mow your lawn during this time of the year, proceed with caution. Always wait for the Frost to go away in the morning and then mow your lawn when the grass is dry. Frost goes away when the sun comes out, and the temperature gets a bit warmer. So, wait for the right time.

If you mow while your grass is still covered with Frost, you will damage the grass’s leaves, and the mower will cut the grass unevenly. Make sure that the grass is completely dry. Mowing wet grass can be as harmful as mowing frosty grass. Moreover, set your mower blades high enough so that you only cut one-third of the grass blade.

How cold is too cold to cut grass?

You should always avoid mowing when temperatures are below freezing. The frozen grass blades are very fragile. As explained earlier, even the act of walking on the frosty grass can damage the grass blades. Similarly, mowing can also cause extreme damage to the frozen or frosted grass, which may weaken or even kill it.

Mowing before Frost or snow is also dangerous as mowing creates a wound on the grass blade, and this wound becomes more susceptible to Frost or snow, which may cause damage to the grass plant. In temperatures below forty degrees, grass growth is very slow, and it can’t heal the damage caused by mowing. So, mowing frozen grass should be avoided at all times.

Early winter thaws

It would be best if you were careful during the early winter thaws. Don’t mow the grass in your lawn right after the Frost or snow layer has melted. Mowing wet grass is always a bad practice as it tears the grass blades and causes additional bruising. Mowing when the grass is frozen or still has residual Frost on it can injure the plant. This causes excessive rupturing of the cells in the plant. Another problem regarding mowing in the winter season is that if you mow your lawn right before the Frost, the grass will become more susceptible to frost damage as mowing creates a wound to the grass plant.

Don’t mow the grass if the conditions are not suitable for mowing. Don’t be fooled by the false thaws that encourage your grass to spring up. Always refrain from improper cold-weather mowing practices; otherwise, you will damage your lawn. In many regions, it’s best practice to stop mowing completely between November and March.

Mowing the grass before the Frost or snow arrives

It is advisable to mow your lawn before you receive the snow. In winter, the grass growth slows down. It is ideal for giving your lawn a last mow before winter, typically just before the temperature dips below forty degrees. So, you can mow before a freeze as long as conditions are above forty degrees and the grass blades are not wet.

If you follow this practice, you will have a great chance to have a robust and healthy lawn in spring. Weather patterns vary region to region and year to year so, there is no typical time to mow your yard for the last time for the year. However, if you live in northern parts of the country, you can mow for the last time in late October and then don’t mow your lawn until March.

Once the temperature is raised and spring sets in, you can resume mowing your lawn.

Mowing height in winter

It can be damaging to leave long grass in winter. In snowy areas, long grass serves as a ceiling that prevents snow from reaching the ground. This may invite voles and vermin who tunnel under the snow to eat the grassroots and damage your yard. If the grass is left long for winters, diseases like snow mold and lawn fungus can also occur. Moreover, long grass stays brown and dormant longer in spring which increases the chances of weed invasion. So, it is a good idea to mow your lawn to a healthy height before winter sets in.

You should mow the grass a little longer than you usually do. For your pre-winter mow, you may add an extra half-inch to your mower height. This will ensure good winter grass health and quick recovery in spring. Mowing cool-season grass before spring to a suitable height before winter also ensures that your grass will grow vibrantly in spring. It also helps in keeping the destructive pests out of your lawn during the snow. Thus, mowing before winter means better grass growth in spring, making your lawn look great and discourages weeds.

Tips for caring for your frozen lawn

  • No activities: Always avoid any traffic on your frozen lawn. The Frost freezes the grass leaves, and they become rigid. The cells rupture and damage the blades of the grass if walked on. Walking on frozen grass may leave unsightly footprints across your lawn which may take months to disappear completely.
  • No mowing: Never mow the frosted lawn as it will damage the grass blades.
  • Avoid mowing wet grass: Avoid mowing the lawn when the grass is wet. Mowing a muddy or wet lawn will damage the grass.
  • Snow molt: To prevent snow mold, mow the cool-season grasses shorter for the final fall mowing.
  • No fertilizer: Don’t apply fertilizer, weed killer, or any other lawn treatment when there is Frost on the lawn.
  • Fertilize in time: Fertilize your lawn before the first freeze to replace all the nutrients that can be lost in the hot summer. Once the weather turns cold, the fertilizer will remain in the soil and feed your lawn’s roots in the winter.
  • Deicers or salt: Be carefull with applying deicers after you shovel snow so the salt doesn’t seep into your grass to reduce salt damage. Also, use calcium chloride-based deicers, which do less damage than sodium chloride-based salts.
  • Clean in time: Always clean your lawn before Frost or snow. Remove all the leaves and debris before possible snow as the leaves trap moisture and encourage fungi growth.

Final Word

Late fall and early winter are always a taxing time for lawn care. Frost and snow can be injurious to your lawn’s health. It is the hardest time of the year for your lawn. The severity of winter affects the grass.

Mowing the grass during this time can do no good to your lawn, ending up damaging the grass. If the days are still nice, wait for the grass to defrost. If the winter really kicks in, the best practice is to mow your lawn before the start of this. Let it grow slowly during the cold winter season so that it stays robust enough to face frosty or snowy conditions.

Growing the grass slightly longer during the cold part of the year will ensure fast healing of the grass damaged by severe winter conditions, and your lawn will quickly regain its lust and health in spring. Keeping your lawn in great shape over the winter doesn’t need to be a worry. It merely requires patience and preparation and a little bit of attention during the nastiest months.