Mowing Dewy Grass – Is It a Bad Idea?

Dewy grass is perhaps one of the best things about getting out before 8 AM. Overnight, the world has turned magical, with tiny dew drops decorating spider webs and the scent of fresh, wet grass enveloping you.

But what if your grass is reaching 3 inches and you need to plunge into that most common of lawn care chores? Can you mow dewy grass?

It’s best to wait for dewy grass to dry before mowing. The extra water droplets will pull grass blades down unevenly, making your lawn look patchy, not to mention make you and your mower work harder.

Since dew usually clears up by 8am, not only will you get along with your neighbours better (no one wants to hear a lawnmower before then) but you’ll also do a better job mowing.

What is Dewy Grass?

Dewy grass isn’t a subspecies of grass, dew is water droplets that form on grass, leaves, spiderwebs, and other things in the early morning. Dew forms when there’s a warm, cloudless day followed by a cool, clear night.

During the heat of the day, water evaporates, and when the air cools, that water vapor condenses into water droplets and coats everything that’s not emitting heat, like the grass, leaves, and spiderwebs. (The ground itself is still relatively warm from the day.)

Can I Mow Dewy Grass?

It’s best to wait until the grass dries rather than mow dewy grass. Wet grass doesn’t cut as well as dry grass, leaving your lawn looking patchy and the grass blades torn, inviting in disease, among other problems. Clumps of wet grass will clog up your mower and block out sunlight on your lawn, making mowing very, very unpleasant. If you wait a few hours until the sun rises higher and dries the grass, you’ll have a much easier, safer time mowing while also doing a better job.

But if the only time you can mow your grass is early in the morning, and your lawn has grown pretty shaggy, then go ahead. Use a push mower (electricity and water do not mix and a push mower won’t disturb your neighbours), keep the mower blades sharp (sharp blades will make it more likely the grass is cut rather than torn), and clean off clumps of grass afterward to prevent rust.

How Long Does it Take Dew to Dry to Mow?

It won’t take too long for dew to dry as the sun rises higher in the sky when the weather is dry and warm. In general, you can mow by 8:00 AM. Between 8 to 10 AM or between 4 to 6 PM are the best 2 times of day to mow.

By mowing after 8 AM, the sun will be high enough to have dried the grass while avoiding the heat of the day. Also, if you live near other people, they will not be happy if you fire up the lawn mower before then!

Can You Mow Dewy Grass With an Electric Mower?

Do not mow dewy or wet grass with an electric mower, especially if you also need to use an extension cord! Electricity and water do not mix and can give you an electric shock. Also avoid using a riding mower, as the riding mower will slip and slide on the wet grass, especially on inclines, and you don’t want to get into an accident.

If you must mow dewy grass, try to use a push mower (for the sake of neighborly love). If it’s a wet lawn later in the day, then you could use a gas mower. Check out our “When is the Best Time to Mow the Lawn, Before or After Rain?” to get a better understanding of when you should mow the grass when it is wet.

Is it better to mow when the grass is slightly damp or dewy or let it grow too long?

The eternal conundrum of mowing! While it’s best to mow when the grass is dry, if it’s been raining for a week straight and the grass has grown too high, you’ll have many of the same problems mowing as you would if you mowed wet grass. Too long grass also clumps and makes the engine work harder.

In this case, avoid mowing when the grass is absolutely sopping (if you step outside on the lawn and your shoes are immediately soaked through, that’s too wet) and try to pick a time when the grass has had as much time to dry as possible.

Sometimes, there’s just no perfect choice in lawn care.

How you can do a better job when you have to mow wet grass

If you have to mow the grass when it’s still wet, here’s a few more tips to doing a better job:

  • keep your mower blades sharp as sharper blades cut rather than tear,
  • clean your mower deck to remove grass clumps and use a little silicone lubricant to help keep grass clumps from sticking,
  • Raise the deck so you’re cutting less grass at any one time, as shorter grass clippings will reduce the amount of grass clumps,
  • Empty the mowing bag to keep weight down and help prevent sinking/ruts,
  • Rake the lawn to lift the grass straighter,
  • Avoid taking sharp turns,
  • Mow slower, as slower speeds will help tires get better traction.

If you can wait until the dew dries, then your lawn will thank you for it. And your neighbours. No one likes the sound of a lawn mower at 6 in the morning.


Leave a Comment