Rainwater Versus Tap: Which Is Best For Indoor Plants?

Tom Gaffey
by Tom Gaffey
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rainwater versus tap which is best for indoor plants

Many plants thrive indoors, but every plant can benefit from nature’s elements. Whether it is nutrient-rich soil or plenty of sunlight, indoor plants require outdoor ingredients even when they are inside. But what about when you water your indoor plants? Many plant owners use tap water to water plants inside the home. While tap water is not likely to kill your plants, you might wonder which is better for your plants: Tap water or rainwater.

Rainwater is almost always better than tap when it comes to watering indoor plants. Rainwater has an ideal pH for plants, and it is often high in nutrients like nitrogen, which plants need. Tap water contains certain chemical additives that are not good for plants. Ideally, you should let your plants get rained on in order for the leaves to get clean so the plant can function properly.

Watering indoor plants is crucial to their survival. Each type of plant needs a different amount of water, and some plants even need a very specific watering routine. But it is not only the amount of water you should be concerned about. You also need to think about the quality and type of water you use to water your plants. Keep reading to learn whether rainwater or tap water is better for your indoor plants, and why.

What Is The Best Type Of Water For Plants?

If you’ve ever walked down the water aisle of a store, you know there are seemingly endless types of bottled water out there. From distilled to tap, and rainwater to spring water, there are all sorts to choose from. But when it comes to “free” water, which is the type pretty much everyone uses for plants, there is really only tap water and rainwater.

While many people use tap water, rainwater is almost always better than what comes out of your kitchen tap when it comes to watering indoor plants. Tap water might be very convenient, but the benefits of rainwater significantly outweigh those of tap.

There are, however, a few instances when rainwater is not ideal. For one, if you live in an area known for pollution and “acid” rain, then it is usually better to have tap water, as it will be less harmful. Also, if you live in a very dry climate, then rainwater might be sporadic and very difficult to collect. This means tap water is the more convenient and reliable method.

Six Reasons Rainwater Is Better Than Tap Water For Indoor Plants

1. Rainwater Has Fewer Minerals And Salts

Rainwater is, essentially, a pure form of water. While tap water might taste and appear to be just as pure, it often contains elements from the ground and the processing facility. Salt and other minerals are often plentiful in tap water. While these minerals are not usually likely to kill your plants in small quantities, they don’t help the plant’s health at all.

2. Tap Water Often Contains Additives That Don’t Help Plants

In addition to naturally occurring minerals found in tap water, there are also additives and pharmaceutical ingredients in tap water that are not meant for plants. Fluoride and other chemicals are found in many water supplies in the United States. Rainwater, since it involves the process of evaporation, is not tainted with most of these chemicals (unless you are somewhere with toxic/acid rain).

3. Rainwater Can Contain Useful Nitrogen And Other Plant Food

One fascinating aspect of rainwater is that while it does not contain the harmful chemicals tap water has, it does have some nutrients. Rainwater contains nitrogen and other nutrients that act as food for plants. This is part of nature’s miracle, providing plants with what they need. Unfortunately, tap water does not contain these same nutrients.

You can always feed plants food that is rich in nitrogen, but it is nice to be able to use natural rainwater to regularly feed your indoor plants.

4. It Won’t Show Up On Your Water Bill

When it comes to watering your indoor plants, one factor that makes rainwater better than tap is that it is completely free. Sure, one plant watering session won’t increase your water bill much, but rainwater is completely and totally free. Further, with ongoing droughts and water conservation efforts, the more water you are able to save, the better.

5. Rain Water Has The Ideal pH For Your Indoor Plants

Plants don’t like drinking just any kind of water. Water that is too acidic or basic can be harmful to plants. This is why acid rain is harmful to plants. While acid rain is not good for plants, usually rainwater is the ideal pH for plants. Plants like water with a pH between around 5.5 and 7. Rainwater has an average pH of around 7, which makes it perfect for plants.

6. Allowing Plants To Get Rained On Helps Cleanse Them

Some people like to collect rainwater for their plants, but it is also possible to put your plants outside during the rain to let them soak up fresh rainwater. This might require some good timing, but there are great benefits to putting your plant out in the rain.

For one, this means you don’t need to collect rainwater or even water the plant yourself. But when you allow rainwater to fall naturally on your pant, it helps you keep the plant and its leaves clean. These clean leaves allow your indoor plant to grow better.

Five Tips To Easily Collect Rainwater For Your Indoor Plants

1. Use Your Gutters To Your Advantage

If your home has gutters that collect lots of rain, use this to your advantage. You can use the runoff to easily collect rainwater when it rains. This method is particularly useful in areas where it rains, but not in abundance. Light rain will collect in gutters but likely won’t gather in a bucket if it is not a heavy downpour.

Just make sure when you collect rainwater in a gutter collector, the water is clean. This means you need clean gutters, and also some sort of screen and filter to help keep the dirt and debris out.

2. Use Screens To Keep Out Unwanted Debris

If you are collecting rainwater outside, you want to make sure you are only collecting water, and not a lot of other natural items. This is where a mesh screen over your rain-collecting bucket comes in very handy.

Using a screen will keep out animals, small critters, and even plant life. This helps prevent mold or other bacteria from entering and tainting the rainwater supply you are using for your indoor plants.

3. Make Sure You Take Measures To Mitigate Mosquitoes

Screens are a great way to keep mosquitoes out of your rainwater. This is important if you live somewhere with mosquitoes because pools of rainwater are ideal breeding grounds for these bugs. Mosquitoes love stagnant water, so small screens, or closed containers connected to gutters, are the best way to keep your rainwater pristine and bug-free.

4. Use An Easy-To-Transport Container

In addition to the collection of rainwater, you also need to consider transporting it from your yard into your home. You should use a container that is easy to open to be able to dunk a smaller carrying bucket into it. Or you can also use a container that is easy to tip, pour or even transport into your home. Making your rainwater easy to collect and transport will it more likely you’ll use this free resource to water your plants on a regular basis.

5. Put Your Potted Plants Outside When It’s Raining

If collecting rainwater sounds like a stressful or overwhelming task, then you might want to consider putting your indoor plants outside when it rains. Putting your plants outside when it rains is a great way to get all the benefits of rainwater. It might be a little tedious (and might get you a little wet in the process), but it means you don’t need to spend any time or money collecting water.

Final Verdict On Which Is Better For Plants: Tap Or Rainwater

All indoor plants need water at some point. Some like to get a thorough soaking and others prefer a rare and gentle misting. But when you water your indoor plants, you should not only think about the frequency in which you water, but also the type of water you use. Tap water might be the more convenient and obvious type of water to use for your indoor plants, but believe it or not, rainwater is almost always better.

Rainwater does not have the chemicals and additives found in tap water, but it does often contain useful nutrients like nitrogen. Rainwater is also free and has an ideal pH level in most cases. If you place your plants outside when it rains, they will also get the benefit of having the leaves cleaned by this nourishing water.

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Tom Gaffey
Tom Gaffey

Tom Gaffey is an expert writer who currently resides in Washington D.C. Tom has a passion for real estate and home improvement writing, as well as travel and lifestyle writing. He lived the last twelve years in Hawaii where he worked closely with luxury resorts and event planners, mastering his knowledge of aesthetics and luxury products. This is where he found his passion for home improvement and a keen interest in DIY projects. Currently, Tom resides in Washington D.C, and also working on his debut fiction novel.

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