Watering Plant Leaves Benefits: Mist Em, Spray Em, Soak Em


As you know, watering is an essential part of plant care. The precious liquid is responsible for keeping plants alive, transporting vital nutrients, and helping maintain structural integrity. But what is the ideal way to water your plants?

Periodic watering of plant leaves has many benefits. Reducing water loss through transpiration is only one. Cleaning leaves in order to promote better photosynthesis is also a significant plus. Though the root system is the main source of water for the plant, wetting leaves also helps.

The following article aims to answer that question. Join us as we look at the various approaches to watering plants, as well as their benefits. We will then be able to determine whether it is better to water plant roots or leaves. Let’s begin!

Should You Water The Leaves Of A Plant?

Does it do any good to wet the foliage of a plant? In a nutshell…yes! 

You can (and should) water plant leaves from time to time. Watering the leaves may help regulate a plant’s water loss in conditions when humidity is low. Plants release water vapor into the surrounding atmosphere when the humidity around them is low. This is known as transpiration.

Of course, as we all know, a plant’s roots are its primary way of absorbing vital moisture and nutrients from the soil.

However, leaves also have a vital role to play in a plant’s water management system. Leaf surfaces are peppered with pores (or stomata) that open up and close depending on the surrounding conditions. While these pores can absorb water into the plant, this is not as efficient as the absorption of roots.

Transpiration is an evolutionary adaptation for ridding a plant of excess water. If a plant is overwatered, its cells may continue to absorb water until they are on the brink of bursting. These burst cells manifest themselves as visible bruising and lesions on the plant’s stem, branches, or leaves.

One of the more popular watering cans you can find today can help you with small outdoor projects and most all indoor plant watering needs. I recommend picking up this watering can for yourself from Amazon.

Transpiration And Damp Foliage

So, how does humidity influence transpiration?

Well, it comes down to water concentration levels, both within a plant and in the air around it. If moisture levels in the air are lower than those in the plant, water will diffuse from the plant, via the stomata, and into the air.

If you want to minimize water loss via transpiration, especially if you have to leave your plants unattended for a few days, spraying the leaves is one way to go about it. Spraying leaves is similar to raising humidity around the plant. In such a scenario, the water concentration in the air will be greater or equal to that in the plant, which stops transpiration.

Of course, this is less effective during periods of low humidity. Heaters and air conditioners are notorious for their negative impact on room humidity, which means you’d have to spray your leaves much more frequently. If you plan on being away for a while, you might need to have a neighbor or friend come over and tend to your plant(s) for you.

If a hose adapter fits your situation better, I recommend this Green Mount watering wand from Amazon.

Watering Leaves Helps Plants Cool Off

Watering plant leaves is also a good way to help them cool off on very hot days. Much like with low humidity, high temperatures can speed up the rate of transpiration and water loss.

Spraying leaves with water also helps plants with photosynthesis.

Cleaning Leaves With Water

Over time, depending on location, plants may collect dust on their leaf surfaces. Naturally, this inhibits a plant’s ability to capture sunlight as the layers of dust serve as a barrier between light and the chlorophyll within the leaves. 

Chlorophyll is a leaf pigmentation that performs multiple roles. One of these roles is the absorption of light, which is then used for photosynthesis. Therefore, more dust or blockages on a leaf’s surface will reduce chlorophyll’s ability to absorb light and, ultimately, the plant’s ability to photosynthesize.

Spraying your plant’s leaves will wash off dust and make the chlorophyll’s job easier.

Pests And Fungi

Some plants (and their leaves) are also susceptible to disease-causing pests and fungi. Hosing the leaves down with water is a good and chemical-free way of getting rid of these problems before they cause serious damage.

Despite all the benefits of watering plant leaves, there are still some measures you can take to avoid problems.

Precautions

We strongly recommend watering your leaves in the morning to give them as much drying time as possible. Leaving the leaves wet may make them vulnerable to diseases, pests, and fungi which thrive in moist conditions. Fungal spores, for instance, are some of the major problems that may take root (pun intended) on your plant leaves.

You should also think about the kind of water you use on your leaves. We recommend that you use filtered or distilled water that is free from particulates. 

Tap water is fine in most cases though. However, tap water may have certain salts that could cause problems. Once the water has dried off, these salts may remain on the leaves and speed up water loss via transpiration. 

To find out more about this and other subjects around lawn care, see my articles…

Should I Water The Leaves Or The Roots?

Is it a one or the other scenario? Can I water both or should I only water leaves or plant roots?

You should water both the roots and leaves of plants. Albeit for slightly different reasons. Watering the leaves of most plants is for cleaning and reducing the effects of transpiration. Watering the roots is the main way to ensure plants have adequate water to survive and grow.

Watering Leaves

Watering plant leaves should be done for the reasons outlined above. This should be done to help minimize transpiration on days that are hot and low in humidity. 

Another reason for watering leaves is to clean them and rid them of parasites. Some plant leaves may absorb water for sustenance but this is less than ideal. Leaves are primarily responsible for photosynthesis and regulating water that is already inside a plant.

Watering Roots

If you want to ensure that your plants stay alive, you should water the roots. 

Roots are specifically evolved to absorb water and nutrients from the surrounding soil. In fact, water serves as a vehicle for some of these nutrients, which simply cannot be absorbed by leaves. 

Plant root cells feature permeable membranes that facilitate the easy absorption of water by a plant. Water in the soil moves across these membranes through a process known as osmosis and enters the plants, where it (and the nutrients it contains) is taken up by the plant’s xylem tubes and distributed to where it is needed.

The leaves are actually some of the major destination points, as water is an essential ingredient in the production of food and the repair of cells. They are not a point of significant water absorption. In fact, a lot of plant leaves have evolved wax-like cuticle layers to make them waterproof when the stomata are closed.

So, in a nutshell, watering leaves helps with external or cosmetic issues, while watering roots is essential for plant survival.

The Final Touches On Watering Plant Leaves…

Though it is true that the main water absorption in plants comes via their root systems, it is also true that there are measurable benefits to spraying, soaking, or misting the leaves. It results in healthier and better looking plants as long as water is not sitting on the leaves for extended periods of time.

Transpiration is a little known attribute of many leaves as an attempt to regulate surrounding humidity levels. This actions can be slowed by wetting leaves and allowing it to evaporate. The result is a better balanced surrounding humidity.

The other benefits include helping photosynthesis by cleaning off dust and debris as well as pests and fungi.

Plant leaves should not be continually damp or mold spores could germinate and cause significant harm to the plant. If regulated well, wetting leaves can be a vital part of proper plant care.

To read more, see these other articles…

References

https://www.gardena.com/int/garden-life/garden-magazine/10-golden-rules-for-watering/

https://todayshomeowner.com/watering-plant-foliage/#:~:text=As%20for%20cooling%20your%20plants,heat%2Dsensitive%20or%20fragile%20plants.

Mathew Booe

Mathew has worked in landscaping professionally for over 10 years. He is a grandpa and frequently interviews other experienced landscapers and lawn care experts who are also grandpas for these articles.

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