Ask A Plant Queen: Is Watering Your Plants With LaCroix A Thing?

I've owned a few plants in my life and thanks to a classic mixture of sunlight, water, and what I can only imagine is pure luck, I have managed not to kill (most of) them. I've never really considered feeding them anything other than tap water, but a friend recently told me about someone feeding their plants LaCroix. It's a thing, they said. You should try it, they said. So I ask you: Is this a thing? Should I try it? Right now, I have a rubber plant [Editor's note: By rubber plant, our advice-seeker doesn't mean a plant made of rubber, but rather the breed known — in plant-expert terms — as Ficus elastica], and I guess I'm curious if watering it with LaCroix or any other kind of sparkling water instead of tap water is a good, bad, or neutral idea. I'm not sure it makes the most sense from a cost perspective, but I guess sometimes you're sipping a carbonated water beverage and you might as well toss some your plant's way, right? Or... not?

When I first read this question, my knee-jerk reaction was to say ‘no way’ to LaCroix, which seem like beverages geared solely toward human consumption. But with a little research and to my pleasant surprise, that initial reaction transformed to a more educated understanding.

But first (!), let’s cover a few basics of what a plant needs to survive, grow, and thrive indoors. The simple breakdown is that plants need air, water, sunlight, and nutrients. Here’s the breakdown, for anyone who needs a biology 101 refresher.

Air: When a plant photosynthesizes they use carbon dioxide to make food, and as a result, release oxygen. So yes, plants do breathe in carbon dioxide and breathe out oxygen!

Water: During photosynthesis, water helps to release energy that the plant has stored. Think of water and water pressure as a major vehicle in promoting healthy stem and leaf growth. And we can thank the roots for carrying the water and nutrients through a plant to facilitate this growth.

Nutrients: Most soils provide plants the nutrients they need. We often encourage people to use fertilizers during the grow seasons (spring-summer) as that helps to revitalize old soils and promote nutrient uptake in the roots. The three major plant nutrients are nitrogen, phosphorus and potassium – which are usually represented by the three numbers displayed on a fertilizer label (i.e. 10-6-5).

Sunlight: The all-important energy from that big, old, star. Plants photosynthesize in sunlight, they take energy from the sun to produce sugars (or food) which in essence, is their fuel to grow. The more sun a plant receives, the faster and stronger it will grow.

Okay, so with the basics covered, let’s get back to the original question of feeding our plants flavored La Croix and/or sparkling water.

The quick answer to feeding your plant, say Pamplemousse, LaCroix is no, not a good idea. Most flavored soft drinks have been infused with artificial flavors, sugars and other unknown elements to a plant. And although we’re clear that plants need sugar to grow, it’s not the LaCroix kind of sugar they are looking for. Flavored sodas could easily damage plant roots, breaking their immune systems down and leaving them prone to disease and death.

Now for sparkling water, which is the part that I found most intriguing.

Believe it or not, the fact is, there could be some benefit in feeding your plant sparkling or carbonated water. To be clear, natural sparkling water (like Pure LaCroix) and carbonated water (like club soda) are different drinks. Natural sparkling water is made by mother nature, with naturally occurring carbonation and minerals, and the other is human made and infused with elements such as, carbonation, salt and potassium bicarbonate.

For the purposes of this column, we’re going to focus on carbonated water (AKA soda water) because there are actual, honest-to-goodness scientific experiments to prove that yes, there are benefits to giving your plants some seltzer.

For example, in 2002 two college students conducted an experiment in which they fed one plant regular water and the other soda water over a 10-day period. The plants were given the same sunlight and planted in the same soil. They found after 10 days, the plant that was given the club soda grew faster than the plant given regular water. Now how could that be?

Well, the simple answer is that soda water is like a supercharged energy pack for plants. Remember our air and nutrient basics? Soda water is full of macronutrients of carbon, oxygen, hydrogen, phosphorus, potassium, sulfur and sodium. These are all nutrients a plant uses and needs to grow and survive on a daily basis. What the soda water provides is a supercharged serving of these nutrients. And I imagine, that sparkling water could also provide some of that supercharge, although this has not been tested or proven.

Another factor for soda water is that carbonated drinks have higher pressures. Could it be that when introduced to plant roots the nutrients are also passed through the plant at a higher rate? Remember our plant basics and that water pressure helps promote healthy growth? Just a thought…

Back to our experimenters from 2002, they admit more testing was needed to confirm whether in the long run the plant would continue to live only on carbonated water. But, if I were to offer my two cents, I'd say don't do it. There is too much packed in carbonated drinks for a plant to withstand healthy growth. It’s like asking you to live on only Red Bull or Coca-Cola for the rest of your life. No, thank you.

In conclusion, a little dose here or there of carbonated or sparkling water won’t hurt your plant and could in fact, promote faster growth. But stay away from feeding your plants flavored sodas.