Lawn Watering

Should you water your lawn and if so by how much and when?

Well here I am, sat here near Cambridge, about to write an article on watering your lawn and its chucking it down outside - makes you realise that there are very few occasions when you have to water your lawn for drought reasons in the UK!

Should you ever water your lawn?

No doubt a few years ago we had several summers where there were extensive periods of dry weather. Many peoples lawns went very brown and looked as though they had died. Water companies imposed hosepipe bans and so you couldn't water your lawn even if you wanted to. So, are we all now a nation without lawns? Well, no, the vast majority of lawns recovered fine - grass is a very hardy species and while it takes some care to look at its best its quite difficult to kill by abusing it.

When should I water my lawn?

If its legal to do so there are a few occasions when you may want to water your lawn and some circumstances when it is highly desirable to.

After feeding

After moss killer

After over-seeding

After Aeration, Scarification

During a Drought

Morning or evening

How often should I water my lawn?

For most things in life little and often is appropriate but not here. That would encourage the grass to develop a shallow root system. This will mean it will not be able to extract enough water in dry weather and hence need more watering!

Aim to water your lawn infrequently but each time give it a good soak. This will encourage a deeper root system meaning it will better tolerate drier conditions and need less watering in the long run. During a hot summer grass can need anywhere between 15-25L of water per m2 to replace the water it has used in a week. If you watered your lawn each week that's an awful lot of water and ultimately you will end up with a weaker lawn.

How to reduce the amount of watering a lawn needs

What equipment is needed to water my lawn?

There are a few options

Watering can


Sprinkler Units

Automated watering systems

How much does it cost to water my lawn?

If your house has a water meter then you will be charged for the water used. Let's estimate that.

First assume your lawn needs anywhere between 15-25L per m2 every time you water it. Using a figure of 100m2 of lawn that is 1.5-2.5m3 of water. With Anglian water that will cost £1.29 for the water used and £1.42 to dispose of it (they assume 90% of used water goes into drains the 10% missing is for stuff like this watering gardens etc).

As a check lets look at it another way. I measured the output from my 40m hosepipe at 0.2L per second (took 10seconds to fill a 2L bucket). Assume you have a sprinkler that can do your 100m2 lawn in two positions say 50m2 of grass each. A typical figure for me would be to leave it on for an hour in each position (feels about right).

That's 720L of water in one hour or 14.4L of water per m2 - about right.

This is another reason not to water your lawn to regularly!


A lawn is like a child if you constantly give it attention it will keep demanding more and never learn to stick up for itself. Get the basics right and it will be strong enough to keep going in the dry times as well as the wet.