Should You Cut Your Grass During a Heatwave?

When temperatures soar, many homeowners wonder whether they should continue mowing their lawn or leave it alone until cooler weather returns.

The answer isn’t quite as simple as yes or no.

While completely neglecting your lawn isn’t usually necessary, mowing during a heatwave requires a different approach to avoid putting unnecessary stress on your grass. Cutting too short or mowing at the wrong time of day can quickly turn a healthy green lawn into a dry, brown patch that takes weeks to recover.

At Cloverfields Gardening, we’ve looked after hundreds of lawns across Bishop’s Stortford, Sawbridgeworth, Harlow, Hatfield Heath, Takeley, Stansted and the surrounding villages, and we’ve seen first-hand how small changes to your mowing routine can make a huge difference during periods of hot, dry weather.

Here’s everything you need to know.

The Short Answer

Yes… You can cut your grass during a heatwave.

But you need to change how you mow it.

The biggest mistake homeowners make is mowing exactly as they would during spring.

Hot weather requires a completely different approach.

Why Hot Weather Stresses Your Lawn

Grass is a living plant.

Just like flowers, shrubs and trees, it relies on moisture to stay healthy.

During prolonged periods of sunshine the soil begins to dry out.

As moisture levels fall, grass naturally slows its growth to conserve energy.

Eventually the lawn may begin turning yellow or brown.

This doesn’t necessarily mean it’s dead.

It’s simply protecting itself.

Every time you mow during this period you’re removing part of the plant that’s helping it survive.

That’s why mowing too aggressively can do far more harm than good.

Raise Your Mower Blades

This is probably the single best thing you can do.

During hot weather…

Raise your mower to its highest or second-highest setting.

Longer grass:

✅ Shades the soil
✅ Keeps roots cooler
✅ Reduces evaporation
✅ Helps retain moisture
✅ Encourages deeper roots

Many people love the appearance of a perfectly short lawn.

Unfortunately, during a heatwave it’s one of the worst things you can do.

Never Remove More Than One Third

Professional gardeners follow what’s known as the One Third Rule.

Never remove more than one-third of the grass blade during a single cut.

Removing too much shocks the lawn.

Instead…

Trim little and often.

Your grass will stay healthier and recover much faster.

Choose the Right Time of Day

Timing matters.

Avoid mowing during the middle of the afternoon.

This is when:

• Temperatures are highest
• Moisture loss is greatest
• Grass is already under stress

Instead mow:

🌅 Early morning
or
🌇 Early evening

The lawn will thank you.

Don’t Cut Brown Grass

If your lawn has already become completely brown…

Leave it alone.

Dormant grass isn’t growing anyway.

Walking across it too much or mowing it unnecessarily simply causes more damage.

Wait until rainfall returns before giving it its first cut.

Leave the Grass Clippings

Many people automatically empty the grass box after every cut.

Instead…

Consider grasscycling.

A light covering of grass clippings acts almost like mulch.

It helps:

• Hold moisture
• Feed the lawn naturally
• Protect the soil
• Reduce evaporation

Just don’t leave thick clumps.

Spread them evenly.

Should You Water Before Mowing?

Not usually.

If watering restrictions are in place, watering simply to mow isn’t recommended.

If watering is permitted:

Water deeply the day before rather than immediately before mowing.

Wet grass doesn’t cut as cleanly and can clog your mower.

Avoid Lawn Feed During a Heatwave

Many homeowners assume fertiliser will green their lawn.

In reality…

• It often makes things worse.
• Fertiliser encourages rapid growth.
• Rapid growth needs water.
• Without enough moisture the lawn becomes even more stressed.
• Wait until cooler weather returns.

Signs Your Lawn Is Struggling

Watch out for:

• Footprints remaining visible
• Grass curling
• Blue-grey colour
• Dry patches
• Brown areas spreading

These are signs your lawn is conserving moisture.

What Happens After It Rains?

Here’s the good news.

Most lawns recover surprisingly quickly.

Within a week you’ll often notice fresh green shoots appearing.

After several weeks of regular rainfall your lawn may look almost exactly as it did before the heatwave.

Nature is remarkably resilient.

How Professionals Look After Lawns During Heatwaves

At Cloverfields Gardening we adjust our maintenance routine throughout the summer.

Instead of treating every lawn the same, we consider:

• Grass variety
• Soil conditions
• Sun exposure
• Shade
• Recent rainfall
• Lawn health
• Usage

Sometimes the best maintenance decision is actually to do less.

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Five Summer Lawn Care Tips

✔ Raise mower height
✔ Mow less often
✔ Leave grass slightly longer
✔ Avoid fertiliser
✔ Stay off stressed lawns where possible

These simple changes can dramatically improve how your lawn copes during prolonged dry weather.

Frequently Asked Questions

Is it OK to mow in 30°C weather?

Yes, but only if absolutely necessary and ideally early in the morning or later in the evening.

Should I water after mowing?

Only if restrictions allow and your lawn genuinely needs it.

Deep watering is always better than little and often.

My lawn has gone yellow after mowing.

Have I killed it?

Almost certainly not.

It’s likely gone dormant and should recover naturally.

Should I mow every week?

Not during a heatwave.

Growth slows dramatically.

Only mow when needed.

Should I collect the grass cuttings?

A light covering is beneficial.

Large clumps should be removed.

Final Thoughts

Hot weather doesn’t mean you need to stop mowing altogether—it simply means you need to adapt your approach. By mowing less frequently, raising your cutting height, avoiding the hottest part of the day, and allowing your lawn to conserve moisture, you’ll give it the best chance of staying healthy throughout the summer.

If your lawn has already suffered from prolonged dry weather, don’t panic. In most cases, established grass will recover naturally once cooler temperatures and regular rainfall return.

If you’re looking for professional lawn care, ongoing garden maintenance, or advice on creating a more drought-resistant garden, the team at Cloverfields Gardening is here to help homeowners across Bishop’s Stortford, Sawbridgeworth, Harlow, Hatfield Heath, Takeley, Stansted and the surrounding areas.