How often should I water my lawn - garden hose in hand

How Often Should I Water My Lawn? (We Have All the Answers!)

One of the most common questions we get asked is, “How often should I water my lawn?”. Unfortunately, the answer is, “It depends.” (Don’t worry, I’ll give you the proper answers below).

But since we’re based in Cincinnati, let’s talk about some general lawn watering as it relates to Southwestern Ohio in particular. Even so, you can consider our advice as generally okay in most non-extreme areas of the country.

Table of Contents

How Much Water Does Grass Need?

So, how often should I water my lawn? It depends on the soil, it depends on the sunshine levels, it depends on where you live.

But a good rule of thumb is that turf (grass lawns) requires between 1 and 1.5 inches of water a week to thrive. It doesn’t matter whether the water comes from irrigation or natural rainfall, or a combination of both.

How Long Does it Take to Water a Lawn?

Here’s chart of the time required to apply 1 inch of water to 1,000 square feet of turf.

Hose DiameterGallons Per MinuteTime (Minutes)
7/16″7.384
1/2″10.956
5/8″15.141
3/4″26.823

Obviously, the larger the garden hose diameter, the more water you can push through in less time.

How Should I Water My Lawn?

Before we discuss how often grass needs to be watered, let’s talk about how it should be watered.

Water Deeply

You should be trying to wet the soil enough, so the roots of your grass get enough water. If you water too much, the water will go below the level of the roots. And if it can’t reach the roots, the water will be wasted.  Deep watering is much better than shallow watering, however.

If you don’t water enough, the grass roots will only grow to the shallowest water level and no deeper. Shallow-rooted grass is prone to more problems (particularly drought) than deeply rooted grass plants.

How often should I water my lawn - grass roots illustration
This soils layers illustration gives you a general idea of the depth of grass roots. You need the water to seep to the depth of the roots but no deeper.

How Often Should I Water My Lawn?

Here’s more information on the general rule of thumb in the turf industry regarding how often to water your lawn.

Water Infrequently

  1. Assuming you are going to apply the standard 1” to 1.5” inches of water per week, apply it as a single dose on regular soils.
  2. At most, split your watering into two equal applications per week. Do not water a little bit every night or three to four times a week. This promotes shallow rooting.

Shallow or too-frequent watering also promotes the growth of weeds such as creeping bent frass and rough bluegrass. It also aids in the germination and establishment of broadleaf weeds such as dandelions.  We like to use the phrase “deep and infrequent” when it comes to watering. 

How Often on Sandy Soils?

On sandy soils, the irrigation should be split into two equal applications because the fast-draining nature of sandy soils means the water will quickly move downward and out of reach of thirst roots.

How Often on Clay Soils?

The one soil that presents more problems with irrigation than any other is a heavy clay. It is almost impossible to say water once or twice a week with these water-repelling soils.

If you have heavy clay in your area (and the Cincinnati area does have a lot of it), and if the soil is dry, you’re going to have to water more frequently than once a week because the small particles of clay won’t allow as much water to penetrate before it starts to puddle and run off.

With dried-out heavy clay soils, apply water until it starts to puddle. Measure this amount of water and adjust your watering frequency to ensure the grass gets its 1 to 1.5 inches of water.

Pro Tip:  Core aeration and introducing compost into your soil can reduce compaction and help to break down clay which will allow water to better percolate.

how often should I water my lawn - shoveling clay soil
In the Cincinnati and Northern Kentucky areas where clay soil is prevalent, you’ll need to water more often.

When Should I Water My Lawn?

Nightime Watering

If you water at night, the turf canopy will stay wet longer. Keeping the grass leaves wet can lead to increased levels of disease, so avoid watering your lawn at night if possible.

Daytime Watering

Watering in the day has its own problem: evaporation. On a hot day, about half of the water coming out of the sprinkler will evaporate before it reaches the solid.

This is costly if you are on a metered municipal water system. Some of that water will evaporate in the air and some will disappear after it has hit the grass leaves.

One consolation is that the water that reaches the grass leaves is cleaning the grass blades (which makes them more efficient) and discouraging insects such as spider mites that don’t like excess moisture.

The Best Time to Water

The best time to water your lawn is first thing in the morning where there is already dew on the ground.

The cooler temperatures reduce the evaporation loss, and the grass leaves will dry off as soon as the sun hits them. If your sprinkler system can be set on a timer, set it for sunrise.

how often should I water my lawn - grass in morning
When you see morning dew on grass, it’s probably the perfect time to water your lawn.

Conclusion

So, how often should I water my lawn? You can see that the answer is more complex than you might have thought. While 1 to 1.5 inches per week is a good standard to go by, there are many other considerations like how and when to do the watering.

Don’t worry. Your lawn should do well if you follow the guidance provided. If it seems a bit too complex, you should consider speaking to a lawn care specialist.

Need More Help?

Need professional help getting your lawn watered on a regular basis? Just contact American Landscapes here for a free, no-obligation estimate. Or call us at (513) 947-8727.

You can also learn more about our lawn care treatments, and outdoor lighting services by reading our blog. In addition to fertilizer and weed control, we also provide mosquito control, lawn aeration, lawn seeding, and much more.

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