Best Time To Water Grass and Lawns For Perfect Results

Maintaining a green, lush lawn isn’t just about adequate sunlight and healthy soil. Correct watering is just as important.

Too little or too much water can cause the grass to die or be prone to pests and disease.

While most of us know the importance of watering the lawn, it can be confusing to figure out exactly how much, how long, and how often to water.

In this article, we’ll provide you with actionable advice on the best time to water the grass, help you avoid under or over-watering, and prevent the risk of disease to keep your lawn in prime condition.

Key Takeaways

  • The best time to water your lawn is in the early morning, between 4 a.m. and 8 a.m., to allow for optimal absorption and minimize the risk of pests and diseases.
  • Avoid watering your lawn in the afternoon or evening, as it can lead to water evaporation, weed invasion, thatch buildup, insect pests, and fungal growth.
  • Water your lawn deeply but infrequently, 1-2 times per week, and adjust the duration based on factors like temperature and grass type to maintain a healthy, drought-resistant lawn.

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When is the Best Time To Water Grass?

The best time to water grass is definitely early in the morning when the air is cool and there is a full day ahead, during which the water will be absorbed into the soil and drawn into the grass.

This leaves the remainder of the day for warmer weather to dry out any remaining lawn surface moisture ahead of nightfall.

This approach will leave your lawn in optimum condition, avoiding the risk of pests and disease.

Best Time to Water Lawn or Grass
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Best Time: Early Morning, 4:00 AM to 8:00 AM

As a general rule, the optimal time to water grass is in the morning between 4 a.m. and 8 a.m., keeping the lawn cooler during the hottest parts of the day, and putting less stress on the grass.

Good Time: Morning, 8:00 AM to 10:00 AM

If you don’t have sprinklers with an automatic timer, it can be a chore to water at this time of the day. So the second-best option is to water late in the morning between 8 a.m. and 10 a.m.

Okay Time: Early to late afternoon, 10:00 AM to 4:00 pM

As the day gets hotter, you can still water your lawn until 4 p.m., but you will need to allow for water evaporation. Try to avoid wet blades of grass going into the evening or nighttime.

Risky Time: evening, 4:00 PM to 12:00 AM

So should you water your lawn in the evening? Let’s face it, most people would ideally prefer to do this job after work when they get home, right?

I would say it’s possible, sure, but you will be leaving your lawn susceptible to the risks of pests and diseases we outlined earlier.

Risks of watering lawn In the afternoon

Watering your grass at the wrong time of day can lead to unwanted problems, including disease or pest and fungi infestations:

  • Water Evaporation: Watering through the hottest part of the day will lead to a high level of wasted water through evaporation. Not good from an ecological perspective and won’t satisfy your lawn’s thirst
  • Weed Invasion: Overwatering will allow weeds to thrive and out-compete your lawn
  • Thatch Build-up: Creates a thick, impermeable layer of organic matter that restricts airflow and water penetration
  • Insect Pests: Grubs, Spittlebugs, and springtails thrive in moist soils, laying their eggs. These insects will feed on roots or new shoots of grass
  • Fungal Growth: Overwatering or watering late in the evening can lead to damp grass through the night. Combined with humid conditions, this is a perfect breeding ground for fungal diseases such as Gray Leaf Spot, Red Thread, and Dollar Spot
Risk of watering lawn in the afternoon
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You’re far better off taking the time to get it done in the morning or investing in a sprinkler system or even a hose pipe timer with a sprinkler head.

How Long Should I Water My Lawn?

It can be difficult to determine exactly how long you should water your lawn, as this will depend on what your water pressure is like, whether you use a soaker hose or sprinkler, and whether your soil is clay or sand-based, affecting the rate of drainage.

But let’s assume you have an automatic sprinkler: you’ll need to water the grass for 30 minutes to an hour, depending on the temperature. On the hottest days, water for longer.

As a general rule, grass needs around 1-2 inches of water per week, either from irrigation or rainfall.

You can apply this in one session or divide it into two watering sessions, depending on how cool or warm the weather is. Your goal is to soak the top inch or two of topsoil to keep your grass green and hydrated.

How Much Water Does Your Lawn Need
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Pro-Tip

Place a clear plastic container on your lawn to catch water during a watering session. Measure the length of time it takes to fill to 1/2 inch. Use this as a guide to how long you need to water for each week to deliver 1-2 inches of water per week.

How Often Should I Water My Lawn

Watering grass daily is never a good idea as it can result in a shallow root system that dries out fast and weakens the grass.

Infrequent watering, on the other hand, encourages the root systems of grass to run deep below ground, thus making the lawn more resilient to disease and weather changes.

The average lawn needs to be watered 1-2 times per week and sometimes more during the warmer months. As previously mentioned, provide about 2 inches of water over the course of the week.

In the cooler months, water as little as once or twice a week since there is a higher chance of rainfall.

Water your lawn twice per week
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Let’s have a quick recap on the best time to water grass, and keep it really simple:

Water deeply not daily

Watering daily will dry out the lawn’s root systems quickly. Water 1 or 2 times per week for a stronger drought-resistant lawn but no more than 3 times in the dry months. It’s better to soak it deep than tease it with water daily.

Water early in the morning, but never Late in the evening

Watering early in the morning before 10 a.m. will ensure your grass has time to dry completely before nightfall.

A consistently wet lawn at night can lead to disease or fungus problems, so if you miss the early morning session, water the lawn late afternoon.  

Water more often in the heat

You can lightly water your lawn every 2 days in the extreme summer heat (90 degrees and over), especially if you have a fescue lawn.

In general, water deeply 1-3 times per week in high temps to prevent your lawn from drying out. Again, the best time to water grass is early morning before it gets too hot, making it a long deep soak.

How Do I Know If My Lawn Needs Watering?

There are some simple ways you can test your grass to see if it’s receiving adequate water: 

Probe the Soil

The screwdriver probe test is a very simple way to check your lawn’s hydration level. After watering your grass, simply push a long-blade screwdriver into the soil.

It should easily penetrate into the soil to a depth of 4-6 inches. If this doesn’t happen, your lawn is dry and thirsty.

Check Grass Color

You can also look at the color of your grass. Is it faded or going yellow or brown? It definitely needs a good soak.

Footprint Test

The footprint test is another simple but effective test. Take a walk on the grass and see if you’re leaving footprints on it. If so, there isn’t enough moisture to spring the blades back into shape. 

Setting Irrigation System Timer

Check the flow rate of your sprinkler system first. Multiply your lawn’s square footage by an inch of water (0.62 gallons) then divide the figure by the sprinkler’s flow rate.

The result will determine how many minutes you should run your lawn sprinkler.

Watering Different Lawn Types

Your grass type and the zone you are in will also determine how long you should water your lawn.

Different grass types will have different watering needs, so it’s important to pay particular attention to the type of grass you’re growing.

Once you’ve identified your specific lawn type, it’ll be easier to set a watering schedule throughout the seasons.

Stick to the guidelines we have outlined for the best time to water grass, this won’t change whichever grass type you decide to grow.

Warm-season lawns

Bahiagrass, St. Augustine, Bermudagrass, carpetgrass, and Zoysia grass grow best when the air temperature is above 80 degrees Fahrenheit.

These warm-season grasses need moisture to remain healthy, so water them 1 inch from late spring to early fall during their active seasons.

Cool-season lawns

Kentucky bluegrass, tall fescue, fine fescue, and perennial ryegrass are some of the most popular grass types that require more water than warm-season grasses.

You must continue watering these grasses during spring and fall and even during winter when they are dormant (up to 2 inches in spring and fall and half an inch in summer and winter).

How Often To Water Grass Seed

How often you should water grass seed depends on the amount of rainfall your region gets after planting the grass seed.

If it’s during the dry season, you will want to water your grass seed twice per day to maintain a few inches of moisture throughout the soil. Check the seeded area regularly and water as needed. 

Tip

A few days before planting new grass seeds, water the soil to a depth of 8 inches. Once you plant the seeds, the soil is saturated with enough water for the seeds to germinate properly. 

How Long to Water New Grass Seed

How long you should water new grass seed depends on your sprinkler system and soil conditions. In general, 5-10 minutes of watering in the morning (between 4 a.m. and 10 a.m.) and late afternoon will be enough to keep the topsoil moist.

Remember the goal is to maintain moisture in the seeded area until the seeds sprout and get established. Otherwise, the seeds will die right after they dry out.

Once your new grass seed grows (3.5 inches), you can water less frequently.

Hang on, at the beginning of this article we said don’t water your lawn in the evening, so how does that work?

Watering grass seed is possible in the evening, due to the water going directly onto the soil and not sitting on existing blades of grass, for the relatively short period of time it takes for grass seed to germinate, you will need to keep them moist. We advise watering seeds twice per day during the hottest days. Just keep the soil damp, not wet.

Best Time To Water Grass

Manual or Automatic Watering System?

Before deciding on whether you should use a regular expandable garden hose or an automated sprinkler system to water your lawn, let’s explain what a sprinkler system is:

Sprinkler irrigation is a similar method to rainfall in that it involves applying irrigation water to grass. Water is pumped through a piping system and sprayed on the grass through sprinklers, just like raindrops. 

This will ensure your lawn gets watered, so it’s best to opt for an automated sprinkler system with a timer.

When properly installed and set up, the sprinkler system will optimally water your lawn at the right time of the day and deliver the correct volume of water.

There is one drawback to automated sprinklers, though: if you’re away on vacation, you won’t be able to turn off the sprinkler when it rains.

As a result, your lawn may get saturated. This leads us to the advantage of manually watering the lawn.

Plus you can always ask your neighbor to water your grass when you’re away instead of using an expensive automated sprinkler.

Having said that, most homeowners with established lawns find automatic sprinklers the most convenient option for irrigating their lawns. 

There is also the option of investing in a pulsating sprinkler that’s connected to a garden hose. This is the next best choice for watering large lawns.

Pulsating sprinkler systems spray water horizontally at high speeds so it’s not vulnerable to evaporation or high winds. 

You can buy battery-operated hose timers that fit on your outdoor garden tap and switch on to open and close the tap at whatever time you set it.

These are great for those early morning watering sessions which we know are the best time to water grass.

Here is a quick comparison of manual versus automatic watering to help you decide: 

If your garden hose doesn’t have a flow-controlling head, it is essentially depositing a large volume of water in a small area while leaving the other sections of the lawn bone dry.

Although manual watering helps conserve water, it’s not the most convenient method.

Automated sprinkler systems may not save as much water, but they save you time as you get to enjoy your day and not have to drag out a hose to water the lawn.

But automatic watering isn’t without fault. You can risk oversaturating your lawn if the system doesn’t come with a sensor to shut off the sprinklers.

Overwatering your lawn is like throwing money away, plus your new grass may struggle to grow or, even worse, die.

You’ll have to stay home for an hour longer to shut off the sprinkler to avoid overwatering your lawn – or better yet, ask your neighbor to keep an eye on the sprinkler!

Final Thoughts: The Best Time To Water Lawn

Frequent or daily watering not only wastes water but also weakens the lawn and leaves it susceptible to disease and pest attacks.

The best time to water grass or lawn is early in the morning or late in the afternoon for about half an hour each session.

Watering your grass for longer but less frequently will produce deep roots and help it survive in hot temperatures.

Taking care of your lawn doesn’t have to be a time-consuming task. With the tips and tricks we’ve provided for you in this article, you’ll help keep your lawn green and healthy for years to come.

Frequently Asked Questions 

Should I water my lawn every day when it’s hot?

No. You’ll risk damaging the grass root system. For best results, water your lawn two to three times a week in the hot season. You can also lightly mist the area once a day to prevent the grass from heat stress.  

Is it bad to water grass at night?

By watering your lawn at night when the sun isn’t around to evaporate the water, you’ll leave it wet overnight and at risk of disease or fungus. It is recommended to wait until early morning or late afternoon to water your grass for the best results.  

Why is My grass dying even though I water it often?

When grass no longer has access to water and nutrients from the soil, it turns brown and eventually dies.

However, if you’ve been watering your lawn correctly, it may have simply gone dormant.

Check the type of grass you have to determine how often it needs watering and look for signs of fungus or disease in your lawn.

Will watering my lawn keep it green?

Yes. Watering your grass deeply and less often will keep it green and healthy. What’s more, infrequent watering encourages the roots of your grass to grow deeper into the soil.

This helps the grass remain green even during extremely hot weather and periods of drought.