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Watering Lawn At Night: Good For Your Grass Or Bad Idea?

Watering lawn at night

You’re not a person who likes waste. So, when you heard that watering during the day was a bad idea because the sun just evaporates the water, you did what seemed like the obvious thing. You switched the timer on your sprinkler system to water at night.

After a while, though, you notice some bare brown spots developing on your lawn. You think your grass must need more water, so you extend your watering time. How frustrating is it when you notice the problems only get worse? Very.

By the time you call in a professional who tells you it’s root rot, the problem has gotten bigger and costlier. Or maybe you hear you have brown patch. What is brown patch? The short answer is that both conditions can turn into huge headaches. Too make matters worse, your lawn technician may tell you that it’s your fault.

How?

By watering your plants at night.

Some homeowners water their lawns based on a common misconception: that our hot summer days make daytime watering useless. If water evaporates before it gets to the roots, you would only assume you should change to night watering.

The truth is: watering at night is a bad idea. That’s why we created this guide about when and how to best water your lawn. Keep reading to learn exactly why night watering leads to issues, as well as when and how often you should be watering your lawn to keep it vibrant and healthy.

Watering at night

Why Watering At Night Is A Bad Idea

If you’re told “don’t water during the day,” it makes sense that your first inclination would be to turn to watering during the night. After all, there are only two options, right? If you can’t water when the sun’s out, you have to do it overnight.

Here’s the problem, though: while too much evaporation is bad, no evaporation is often worse.

Many fungal and bacterial diseases that can harm your lawn and your plants thrive in wet foliage. With no hot sun to burn it off, excess water just sits there. All. Night. Long.

It’s like you’re turning your lawn into a petri dish and trying to breed bacterial and fungal diseases. Yard fungus is just as bad as it sounds.

If you shouldn’t water your lawn during the hottest part of the day or at night, what other option is available?

Best time to water lawn in hot weather

Best Time To Water Lawn In Hot Weather

Your clue about when you should be watering your grass is in that phrase above: “during the hottest part of the day.” It’s not all day that you need to avoid, but just the hottest parts of the day.

Think about when it’s warmest where you live. For most of us, that means late morning, the middle of the day and during the afternoon and early evening before the sun sets.

If you try to water your lawn during these times, most of it absolutely will be evaporated before your grass and plants can soak it in and benefit from it. You will end up with thirsty roots that aren’t getting the moisture they need, especially during when the temperatures are consistently high and there is less rainfall.

The options mentioned above are not the only times of the day though. What’s missing? Early morning.

Set your sprinklers to water relatively early in the morning. The water will then have time to soak into the ground. At that time, your plants’ roots will have time to drink their fill.

Then, by the time your sprinklers are done, the sun will be stronger. Any leftover moisture will be baked away rather than sitting there on your lawn, encouraging disease.

How often should I water my lawn with sprinkler system

How Often Should I Water My Lawn With A Sprinkler System?

How often should you water? Let’s answer that with another question: what kind of soil do you have?

This is important to know, because typically you want to water sandy soils every three days or so, while clay soils only require water about once a week.

Not sure exactly what type of soil you have? No problem. There are many fairly easy ways to test it, including some DIY methods.

Just as important as frequency, you need to know how long to water your lawn each time you do it. Ideally, you want to keep the water running long enough for moisture to soak six inches deep into the soil.

Why? Simple. That’s how deep grass roots generally grow.

What’s not so simple is knowing how long it will take the water to soak down those six inches. Unfortunately, we have some bad news for you: every lawn is a bit different. How often and how much you should water depends on the makeup of your soil.

You can generalize, but the best way to know for sure is to turn on the water for your regularly scheduled watering, grab a shovel and dig up the topsoil after about 15 minutes. You’ll be able to feel how far down the water has penetrated and gauge how long you need.

In some lawns, that first 15 minutes may be enough. Most, however, will probably need a bit longer.

This is especially true for many lawns in newer developments, because often builders end up unintentionally packing the ground down as they engage in construction, leading to hard, nonporous soil that needs to be softened before they can soak in the water.

For these types of lawns, we recommend breaking up your watering sessions. In other words, you want to water for 15-30 minutes, turn off the water to let it soak in for a bit, then water for another 15-30 minutes. Doing this prevents the water from pooling on the top and simply running off.

When Should You Water Your Lawn In Cooler Weather?

While longtime residents know that there are very definitively four seasons in the south, they’re not quite as distinct as the traditional seasons we learn about in school.

This is especially true where lawns are concerned. Generally speaking, we have a hot growing season and a cooler mostly dormant season.

Which begs the question: should you change when you water your lawn in the fall and winter?

Yes and no.

Why the complicated answer? Most of the time the answer is yes (though not in the way you probably think), but in some situations, it’s a no.

How so?

Here’s the thing. Most people in the south probably won’t need to water their lawns over the cooler parts of the year. Even in low-rain areas, there’s usually enough water to support the roots. During this time of year, that’s really all you need.

However, if you experience a long period without rain and feel the need to give your lawn a little H2O pick-me-up, you should follow the advice above–water in the early morning. You’ll want to do this for all the reasons already mentioned. Even though the sun isn’t as strong in cooler weather, it still helps to evaporate the water.

When to start watering lawn

How To Know When To Start Watering The Lawn Again

Okay, so let’s say that you got through the cooler winter months without any watering. Congratulations! You know you will have to start up again at some point, though. As the weather starts to get warmer, you find yourself asking the question, ‘When is the right time?’

Should you just go back to your “warm weather” schedule at the beginning of spring? Do you wait until the grass begins growing again and you have to start cutting it?

While you don’t want to wait until your lawn starts looking sickly and brown, most people actually misjudge and begin watering too early in the year.

So how do you know when to start back up with watering your lawn?

Check the weather. The most basic rule is that you do not need to worry about watering your lawn until the weather is hot and dry.

In other words, if you’re getting a good amount of spring rain, you can wait. If you touch your lawn in the morning and your fingers get wet with dew, you can wait.

To keep your lawn as healthy and resilient as possible, the best thing that you can do for it is to wait to start watering until it really, truly needs it. A little bit of stress should actually cause your roots to grow deeper as they seek out water, making them stronger.

ABC Can Ensure Your Lawn Is Always Healthy and Green

Keeping your lawn appropriately watered and vibrant isn’t always as easy as it sounds, especially if you don’t have a good sprinkler system or if yours isn’t working properly. If you want to upgrade or repair your system to help maintain your lawn, do not hesitate to turn to the experts at ABC Home & Commercial Services. Our knowledgeable lawn and sprinkler technicians can advise you on the type of watering and sprinkler system that is best for your soil and even help you program it properly so you never have to worry. Good lawns require work, but you can still make that work a little bit easier with the right advice and the right tools.

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