Leafy Air Filters: Moving Houseplants Indoors to Clean Indoor Air

In addition to enhancing décor, houseplants actually DO clean indoor air! A famous study by NASA scientists concluded that indoorplants remove several common pollutants from the air by absorbing them into the pores of their leaves, in the same way they take in carbon dioxide during photosynthesis.  Although the experiment took place in a sealed chamber, today’s tighter, more energy-efficient homes are approaching this model far more closely than drafty, older homes. 

A 2011 article in The Wall Street Journal championsthe role of “The Mighty Houseplant” in purifying the air, citing several studies.   The story explains a growing body of global research shows plants can reduce pollutants including dust particles and contaminants such as formaldehyde and benzene that come from cigarette smoke, paint, furniture, building materials, cosmetics, dish detergent, fabric softener, carpet cleaner, and other sources.

The U.S. Green Building Council, which certifies buildings based on environmental standards, cautiously agrees, noting while "using plants to help clean air is a great strategy…we've had difficulty quantifying the results.” 

The EPA notes that people spend more than 90% of their time indoors, where levels of a dozen common Volatile Organic Pollutants (VOCs) can be two to five times higher than outside. 

In 2009 Live Science ran an article about houseplants making air healthier. 

Also that year, University of Georgia scientists Bodie Pennisi and Mussie Habteselassie identified five "super ornamentals"—plants that showed high rates of contaminant removal when exposed in gas-tight glass jars to common household VOCs, such as benzene (present in cigarette smoke), and toluene (emitted from paints and varnishes). They are: the purple waffle plant, English ivy, asparagus fern, purple heart plant, variegated wax plant.  

purple waffle plant photo from
Wikipedia byTau'olunga

UGA aims to broaden these findings by developing a simple test kit homeowners can use to check for VOCs, as well as an expanded list of plants and their associated pollution-fighting abilities. The university also sees a potential market for enhanced potting soil and other media.

Deborah Brown from the University of Minnesota Extension suggests that the "liberal use of houseplants indoors seems like an easy way to make a dent in the problem".  Crabapple agrees. 

Thinking ahead?  Before you bring houseplants indoors for winter you may want to inspect, clean, and prune or repot them. Seeour Crabapple Blog from last fall to get all the tips.