Did You Know that Houseplants Sweat?

Yes, you heard that right. They sweat.

Of course, things are a little different when houseplants sweat. For one thing, their sweat doesn’t smell like human sweat can. They don’t sweat out last night’s garlic heavy dinner. And they don’t sweat salty sweat like we do. But they do sweat.

Houseplants Transpire

You know how we perspire? Well houseplants transpire. So what’s the significance of all of this transpiring? It turns out that the transpiring serves a function. It’s actually a necessary process that enables houseplants to clean indoor air for us. You know—cleansing the air of toxins with names that are hard to say or sound like they belong in a horror film (formaldehyde.)

In the transpiration process, when moisture passes through plant breathing pores (stomata), plants release water into the atmosphere from their foliage. This has a suction effect that causes the plants to constantly pull water up through themselves from the soil (or the water in hydroponic situations.)

You may experience a plant transpiring when you see what looks like waters drop coming from its tip or somewhere on the foliage. You might even wonder where the water is coming from and even look at the ceiling. No worries! The plant is just transpiring. This is also known as guttation.

Houseplant Transpiration Leads to Clean Air

So why am I telling you this? Well, for one thing it’s really cool to know that plants do sweat. It’s fun party talk. For another, it’s good to know that you want your plants to sweat. When they do, they do a really good job of cleaning your indoor air of yucky stuff.

That being said, it’s important to keep your houseplant leaves clean, so that the stomata can stay clear, and the plant is able to transpire. This means cleaning the foliage on a regular basis. No matter how clean you keep your indoors, plant leaves collect dust and even grease when the plant is near the kitchen.

Rinsing is the easiest way to clean your small and medium-sized plants. Transport them to the sink and gently run water over the foliage. Small plants can even be picked up, turned over and dunked completely in water. Secure the soil in place with a paper towel or rag and gently swirl the foliage for several seconds.

Larger plants that are more difficult to move can be cleaned in place. Wipe both sides of each leaf down with a damp cloth. Use a material that is soft, so that you don’t scratch the delicate leaf surface. To kill off any latent pests, add insecticidal soap to your cleaning water. 

Clean Large Houseplants Regularly

Though they are hard to move, it’s generally a good idea to hose off large plants two to four times a year. This can be done in the shower. Just make sure that the showerhead sprays gently and that you use warm water. Tip the plant at a 45 degree angle, so the rinsing water washes into the tub rather than into the soil. You can also let nature do the dirty work and shower your plants in a gentle rainstorm. They’ll return to the indoors clean and rejuvenated. Just make sure that they aren’t left in the sunlight!

In order to keep leaves breathing and transpiring, avoid leaf shine products. Although they create a glossy sheen, they block the plant’s stomata and cut off transpiration, as well as light. Think of it this way. Would you want to put a coating of wax on your skin? Homemade concoctions such as cooking oil and mayonnaise also clog stomata and make a big mess, plus attract pests! The best way to clean your houseplants is with a light spray of water and microfiber cloths, which won’t scratch foliage.

Well, there you have it. Your houseplants may not be sweaty and smelly, but they do sweat!