Can You Mow the Lawn When the Grass Is Wet?

Can you mow the lawn when the grass is wet?

Yes, you can. Your mower will still turn and the grass will still be shorter at the end of it. But if you've got the choice, waiting for the lawn to dry off will give you a cleaner cut, a healthier lawn, and a lot less mess. After a wet Sydney week that "if you've got the choice" bit is the catch, so let's go through when it matters and when it really doesn't.

Why mowing wet grass causes trouble

Wet grass behaves differently to dry grass, and not in your favour:

• It clumps. Damp clippings stick together and to the underside of the mower deck, then drop out in heavy mats that smother the lawn underneath. You end up raking up rows of wet clippings instead of a tidy finish.
• It tears instead of cutting. Wet blades bend and slip away from the mower instead of standing up to be cut cleanly. A torn tip browns off and gives the whole lawn a ragged, slightly yellow look a day or two later.
• It rutts soft ground. This one's the big one in the Hills. A lot of local yards sit on clay, and after rain that clay goes soft. A mower's wheels, or your feet, leave ruts and compacted tracks that take weeks to recover.
• It spreads lawn disease. A mower is brilliant at moving fungal spores around a wet lawn. If one patch has a problem, mowing wet is how it gets introduced to the rest.
• It's harder on the mower. Wet grass packs the deck, bogs the engine and clogs the chute. Petrol mowers cope better than most electrics, but nothing loves it.

None of that is a disaster from one wet mow. It's the regular wet mowing that slowly wears a lawn down.

So should you mow a wet lawn, or wait?

If it's just morning dew, you don't need to wait for the whole day. Give it until mid-morning once the sun's been on it and the surface has dried, and you'll be fine. That's a normal mow.

Can You Mow the Lawn When the Grass Is Wet?

If it's been properly raining and the ground squelches when you walk on it, hold off. The lawn won't suffer for being a few days longer, but soft clay will absolutely remember your wheel tracks. Wait for a dry window.

The honest truth is that around here you don't always get a dry window. We can go a fortnight where the only dry hours are the ones you're at work. Which brings us to the realistic version.

When wet mowing is unavoidable: how to do it properly

Sometimes the grass is romping away and the forecast says no, and you just have to get it done. If that's the call, here's how to take the sting out of it:

Can You Mow the Lawn When the Grass Is Wet?

• Raise the cutting height. Take less off than usual. You're tidying, not scalping. You can drop it back to the normal height on the next dry mow.
• Go slower, in narrower passes. Half-width passes give the deck less to choke on and throw a much cleaner line.
• Side-discharge or bag, don't mulch. Mulching wet clippings is how you get those smothering mats. Throw them clear or catch them.
• Keep the blade sharp. A sharp blade is the difference between cutting wet grass and dragging it. Dull blades tear dry grass too, but wet grass shows it instantly.
• Clean the deck afterwards. Wet clippings set like concrete under the mower and hold moisture against the metal. A quick scrape saves you a rusty deck and a worse cut next time.

A note on Hills lawns specifically

A lot of the lawns we look after through Kellyville, Castle Hill and Baulkham Hills are buffalo (soft-leaf Sir Walter and the like) with a fair bit of kikuyu and couch mixed in. Buffalo likes to be left a touch longer at the best of times, so it's very forgiving of a "we'll wait until it dries" decision. Kikuyu, on the other hand, doesn't so much grow as commute over summer (blink and it's across the path again), so it's the one that tempts people into a wet mow. Even then, a raised, gentle cut beats a hard wet scalp.

The easy version: leave it to someone who watches the weather

Picking the right window is half the job, and it's the half that's hard to do when you're flat out during the week. Looking after that timing, turning up when the lawn's actually ready, not just when it's on the calendar, is a big part of what we do. As one of our Castle Hill regulars, Chris, put it: "Don contacted me in advance and arrived on time. He did a great job mowing the lawn and left everything clean and tidy afterward." Right time, clean finish: that's the goal, wet week or not.

If you'd rather not stand at the window waiting for the grass to dry, we're happy to take it off your plate. We run a roster across the Hills District and send a reminder about a week before each visit, so you always know roughly when we're coming. Have a look at the suburbs we cover, our lawn mowing service, or grab a free quote. No lock-in, and the first thing we'll do is give you an honest price.

Quick answers

Will mowing wet grass ruin my lawn?

One wet mow won't hurt, but doing it regularly will. The clumping, tearing and wheel ruts in soft clay add up over time.

How long should I wait to mow after rain?

Wait until the surface has dried and the ground feels firm underfoot, often a day or two after solid rain around the Hills.

Is it okay to mow with morning dew on the grass?

Usually yes. Give it until mid-morning once the sun's been on it, and it'll mow much like a dry lawn.

Related reading: How often should you mow your lawn in the Hills District? · How much does lawn mowing cost?

Useful background: Lawn Solutions Australia on lawn health, and Sir Walter buffalo care for the soft-leaf lawns common around here.