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Why Is Grass Wet In The Morning? (5 Things You Need To Know)

Have you ever woken up to find your grass wet even when you didn’t water it the day before? What might be even more confusing is that there was no rain last night. So, this could leave you wondering – why is grass wet in the morning?

There is a clear explanation for your query. Your grass is wet in the morning due to the dew that fell on the ground last night. Dew is the condensed form of water present in the air as water vapors and appears on your grass, spider webs, and some other places because of the temperature change.

Let’s dig deeper into your question – why is grass wet in the morning and find out the chemical change behind the scenes. 

Why Is Grass Wet In The Morning
Wet grass in the morning sun – via Wikimedia

Why Is Grass Wet In The Morning?

The dew on grass shows in the form of small droplets, subtle moisture, or slightly damp surfaces in the morning. The dew might leave light stains on things left outside, like shoes or the roof of your car.

This dewy grass is formed mainly due to some reasons that include environmental changes. Keep reading to know the details of exactly why is grass wet in the morning.

What Does Wet Grass In The Morning Mean?

The wet grass in the morning shows that the night was cooler than the morning. It shows the difference in temperature in the morning and at night. The previous night needs to be cool and clear for the dew to form the following morning.

There will be no indication of clouds or rain in the evening and it will be succeeded by an equally clear day. This is because clouds prevent the dew from forming on the ground.

If there are clouds formed in the evening, the heat erupting from the ground is reflected back to the ground. This does not give the ground time to cool off and form dew at night. So, the night must be clear of clouds or indications of rain. 

Dew can form after rain as well when the water is covering the ground if the weather is warm. The high temperature will cause the rainwater to evaporate in the form of humidity. If the temperature drops down to a certain level at night, the vapors might start to condense and form dew. 

How Does Dew Form?

Water exists in three states – solid, liquid, and gas. While you may not be able to feel it on your skin directly, there is water in the gaseous form present in the air. This gaseous form is called water vapors, and they determine the humidity level of the air surrounding you. The humidity is higher when the temperatures are high such as in the summer season.

The water vapors in the air do not stay in that form always. They change form with the environmental changes. When a warm, clear morning is taken over by a colder night, the vapors are affected.

In the warm morning, any moisture on the grass would have evaporated in the air, but when the colder night arrives, the water vapors condense due to the lower temperature to form dew on the grass and a few other surfaces.

The dew is formed when the temperature reaches the dew point. As the temperature keeps falling below the dew point, the dew keeps coming down from the air. Once the sun rises or the temperature starts to rise, the dew disappears from the grass.

Dew is mostly formed on surfaces that are not radiating active heat, such as leaves, grass, and cars. This is why you will not see a high amount of moisture on the soil or directly on the plain ground. Rather, the moisture condenses on the cool metal surface of the cars and grass, which are not throwing off heat.

Why Is Grass Wet In The Morning 2
via Pxhere

What Is Dew Point?

The Dew point is the temperature at which the humidity or water vapors in the air condense to form dew or water. At this point, the air cannot hold moisture as vapors, so they condense to form dew. The dew point is always lower than the temperature of the surrounding air.

The lowest temperature of the night is usually reached right before sunrise. When you see dew on the grass in the morning, know that the water vapors had to condense because the dew point temperature was met at night.

Does Dew Affect Your Plants and Garden?

If you water regularly in the morning, you must be wondering how the dew affects your schedule and if you can still water. Normally, the grass needs a lot of water – up to 1 inch per week. This means you need to water at least 2 to 3 times a week to fulfill the requirement. When compared to the water requirement, the dew formed on the grass is very little.

So, you can water your lawn in the morning with the dew on it. It doesn’t affect your grass. Some plants have evolved to grow on little water, so they may make full use of the dew and grow just fine on it but not the grass.

How to Handle Dew on Your Grass?

You do not need to do anything to the dew. It will evaporate in the morning sun within 2 to 5 hours. You shouldn’t cut the grass when it is wet with dew as the grass blades may break, leading to a deformed and vulnerable to attacks from pathogens.

Sometimes, the excessive wetness may cause fungus and bacteria to grow around your plants. If such attacks do not easily take over your plants, your lawn will be fine with the dew.


Conclusion

I hope this answers your question of why is grass wet in the morning. You can be assured that it wasn’t sudden rain or storm that caused that mild wetness in the grass. Most of the time, the dew evaporates soon after in the morning. Dew gives your grass a refreshing look, and you can feel the purity around you during such mornings.

You can sometimes tell the dew will form in the morning by noticing the light wind, clear skies, moist soil, and low nighttime temperature. So, it is nothing to worry about when moisture suddenly comes over your grass in the night or morning, and you have no idea where it came from.

Have you ever observed the dewy grass from up close?