What Temperature is Too Hot to Mow Grass?

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It could be hot outside, but your grass has grown too long. Should you mow it or wait?

What temperature is too hot to mow your grass? It is too hot to mow the grass in your yard when it is above 26C (80F). The best thing to do is to wait until the heatwave passes.

When is the Best Time of Day to Mow Lawn in Hot Weather?

While it is best to avoid mowing cool-season grass during heat waves, if you really need to cut it, the perfect time of the day to mow it is in the evening.

Without the sun blazing down on it, the grass will have all night to recover and preserve its moisture.

What’s the Best Temperature to Mow Grass?

The ideal temperature to mow your grass ranges from 10C (40F) to 26C (80F). If it is below the recommended temperature, the grass might not grow.

Temperatures that are above 40F and 80F will make the grass to be dormant or heat-stressed.

You should be careful about mowing grass in hot temperatures because it might result in dehydration and heatstroke, according to Rhys, landscaper at Mower On The Lawn.

Is it Better to Leave Grass Longer in Hot Weather?

Yes, it is okay to leave the grass longer in hot weather. 2 inches is best suited for warm-season grass while 4 inches is a great fit for cool-season grasses.

Longer grass enables the grass to extend roots deeper into the soil. This will make the roots have enough access to water and be safe from the heat.

The extra shade keeps more moisture in the soil and also protects the beneficial microbes in the soil.

What temperature is too hot to mow the lawn?

Do not mow grass when:

  • The grass has gone dormant due to the summer heat for cool-season grass or during winter for warm-season grass.
  • Do not mow your grass during a heatwave. If it requires a cut, you can take a few shallow cuts (not more than 1/3 of the grass’ current height).
  • Do not mow when the grass is not growing, especially in daytime temperatures that are constantly below 10C (40F) and in early spring.

How to Avoid Heat Exhaustion

Heat exhaustion can have serious consequences. When you are exhausted, you are prone to making serious mistakes while mowing.

It is best to avoid working outside in midday during high temperatures or heat waves. If it isn’t possible, then:

  • Drink a lot of water.
  • Wear a hat and sunscreen. Ensure that you re-apply the sunscreen as directed.
  • Wear light-colored, lightweight and loose-fitting clothing like leg protectors.  Do not wear polyester and jeans. Go for natural fibers like linen and cotton.
  • Make sure that you rest frequently in a cool and shady area.
  • Hot and large meals can increase your body temperature, so it is better to eat cool and light meals.
  • It is advisable not to mow at the hottest part of the day.

What Temperature is too Hot to Water Grass?

No temperature makes it too hot to water the grass. If the grass of your lawn is wilting, you should water it, even in the mid-afternoon during a heatwave.

Once your grass gets to a terminal wilt stage, it means that it is dead. Watering when it’s hot does not cause leaf scorch. 

Apart from wilting, it is ideal for you to mow your grass in the morning before temperatures rise above 24C (75F). It will give the water time to soak into the soil for a long time. If the grass has gone dormant, there is no need to water it frequently.

One of the important things to getting your desired lawn shape and beauty is being intentional about when you mow and how you do it.