There’s something about house plants that makes a place homier. Bringing green into your home feels comforting, especially in winter months when the plants outside are often dormant, bare or brown. Plus, we know that plants breathe in carbon dioxide and breathe out oxygen. This is at the core of the symbiotic relationship between animals and plants. But even good indoor plants do even more than we realize.
In addition to providing air for us to breathe, indoor plants clean the air as they do so. We may not think about it but indoor air pollution is a real thing.
Airborne particles can contain harmful chemicals from cooking, cleaning, environmental heating and cooling, mold and pollen, tobacco smoke, building materials (e.g., asbestos), paints and solvents, machinery, radon, office products (think printer toner and whiteboard markers), and many other potential sources. In fact, indoor air can be up to five times more polluted than outdoor air. (1)
As plants breathe, they filter the air (biofiltration). This is good news for animals (humans included), as many of the pollutants found indoors are cleansed by houseplants. (2)
Watch this short video that shows how it’s done:
If that’s not enough, plants also help cool your home.
That’s right: plants draw moisture from the soil in which they’re planted through the roots. In a process called transpiration, moisture is drawn up into the stems and leaves. Like human perspiration, some of this moisture is released to the underside of the leaves and evaporates into the air. You may not see the water as you would your sweat after a workout but to give you a sense of scale: a large oak tree can transpire 40,000 gallons of water a year! (3) Like human perspiration, the evaporation process cools the leaves and surrounding air. Water from moist soil also evaporates into the surrounding air, multiplying this effect.
It’s been generally found that good indoor plants with high transpiration rates are also the best air cleaners, as air is pulled down into the plant to the roots as the water evaporates. (4) As summer approaches in the Northern Hemisphere, we start to think of long warm days—sometimes too warm for comfort. A total win-win way of naturally cooling (and purifying) your home’s air is by adding some key houseplants whose transpiration rates will help to keep you cool as well.