Can I Water My Plants with Soft Water?

Your house plants can really brighten up a space. They’re a symbol of vitality. But only if we can keep them healthy! A sad and yellow or wilted plant isn’t doing anyone any good. A little sun and the right type of water can help them thrive.

About Tap Water for House Plants

Water is water, right? Well, not exactly. The tap water we get from the water treatment plant is completely different than, say, well water. Tap water is also different than rainwater. And when it comes to watering your plants, rainwater should be the obvious choice. There’s more than just H2O in our tap water. Most families are already familiar with the fluoride added to our water. But we tend to forget about the chlorine disinfectant that’s used to treat our water.

Certain levels of chlorine remain in our tap water as it travels from the treatment plant to our home. Without a particular home water filtration system in place, we’ll then shower in that chlorinated tap water. And we might even give it to our plants. Either scenario is far from healthy.

To counteract these chlorine concerns, some homeowners choose to install a water refiner. Also called a chlorine removal system, these units work to filter your plain tap water. So instead of having chlorinated tap water, you get chlorine-free water all throughout your home. In theory, this should be better water for houseplants. Rainwater doesn’t have chlorine, so why should we add chlorine to our plants?

Another Feature of Rainwater

Another difference between tap water and rainwater relates to hardness, or the amount of dissolved minerals in the water. Our tap water in Indiana is notoriously hard. This means it has high levels of dissolved calcium and magnesium in it.

Around the house, hard water is responsible for that hard, white crust around your faucets, or the green stuff on your shower head. The minerals get left behind on these fixtures and turn into scale. They also create water spots on your clean dishes and make laundry feel rough and scratchy. A home water softener helps reverse these problems. These units remove the dissolved minerals in hard tap water. The result is soft water, which is quite similar to rainwater.

Rainwater is naturally soft. It doesn’t contain those hard water minerals. In that sense, it’s easy to think that soft water is better for house plants than plain, hard tap water. If soft water is like rainwater, then you might think it’s the clear winner. But some people still have concerns.

The Deal with Soft Water Salt

The debate around soft water for plants revolves around water softener salt. Because of this, soft water (from a water softener) does have a slight difference from rainwater. See, most softeners use special salt in their process. Put simply, this works to swap the calcium and magnesium for low levels of sodium.

But let’s be clear: Soft water isn’t salty. Just compare its sodium levels to other food and beverages. A teaspoon of table salt comes with 2,300 mg of sodium. A slice of bread can have anywhere from 80 to 230 mg of sodium. It just depends on the brand. Even low-fat milk has sodium. There’s abut 120 mg in an 8-ounce glass. The levels in all of these items are in stark contrast to the sodium levels in soft water. While the low level of sodium will vary depending on the water source, a good average is about 20 mg of sodium for 8 ounces of soft water.

Food and beverages labeled by the FDA as Low Sodium come in at 140 mg of sodium or less. Very Low Sodium covers anything with 35 mg or less per serving. Given those parameters, soft water from a home water softener can be anywhere from Very Low Sodium to Sodium-Free. That should hardly be a problem for most house plants.

Naturally, we don’t want to give our plants salt water. But since soft water barely registers with sodium, it’s much more similar to rainwater than your other options, like hard, chlorinated tap water. So yes, soft water is safe to give to your plants.

Other Plant Water Options

If you’re still on the fence about giving your plants soft water though, you have other options. You can always stick with the original soft water—rainwater!

Collecting rainwater with your own backyard rain barrel is a great way to garden. It will fill up on those rainy days and give you a great supply of water when we get into hot summer weather. You can also choose to give your house plants reverse osmosis water.

If you have an RO filter in place, this can be a great water source for everyone in your home. (Pets and plants included!) If you have both a water softener and an RO system, the powerful RO filters will remove sodium in your drinking water, too. Compared to tap water, soft water, rainwater, and RO water all tend to be superior choices for watering your plants. We always think it’s better to upgrade your regular tap water. If you have any other questions about the water softener and water filtration system in your home, be sure to send us a message!