With their emerald colored leaves and pale yellow spike partially cupped inside a white petal, the easy to grow – just plop them in the shade and water once a week--Peace Lily seems a gentle plant, perfect for adding color to the gray winter days ahead.
But back off volatile organic compounds (VOCSs) because Spathiphyllums is no fragile flower. This pugnacious plant is on NASA and the Associated Landscape Contractors of America list of 15 houseplants that help clean the air in our home, removing three of the most common VOCs-- formaldehyde, benzene and trichloroethylene along with such other nasty compounds floating through our house unknown to us like toluene and xylene.
And boy, do we need these plants on our side. An article in "Science News" reported the United Nations Development Program estimated that more than two million people die each year due to the presence of toxic indoor air, while other studies estimate that 14 times as many deaths occur globally from poor indoor air quality compared with outdoor air pollution.
According to Chuck Roth Jr., owner of Chesterton Feed and Garden Center in Chesterton, spider plants—those holdovers from the 1960s which used to nestle in macramé holders in many college dorm rooms—also make the Top 15. Taking on foes like benzene, formaldehyde, carbon monoxide and xylene, a solvent used in the leather, rubber and printing industries, Chlorophytum comosum has the added advantage of being super easy to grow (just try to kill one) and it’s cascading miniature plants that give it the spider name make propagating a breeze.
Filling your home with houseplants is more important today with the way new construction seals a home to cut down on energy loss from furnaces and air conditioning. Add to that the VOCs in many home items—furniture, drywall and carpeting to name a few, creating what is known as the Sick Building Syndrome.
“I have a robust Boston fern which reputedly takes formaldehyde out of the air and adds humidity to the dry winter air,” said Peg Mohar of Chesterton, property assistant for the Shirley Heinze Land Trust where she has also served as the organization’s Executive Director, Board Vice President, and Board Secretary. “My angel-wing begonia thrives indoors and even flowers during the frigid months. A monster 25 year old staghorn fern has a lot of leaf surface, so I am counting on it to do its share of air filtering. I also have red and green shamrock oxalis, philodendron and jade plants to pick up what the others don't clean up. These are all plants which summer on the deck and have just come in to their winter home within the last week. The deck surely looks bare, but they have cheered up the house.”
The leafier the plant, the more likely it will help the air quality in the home says Ross noting that all plants are healthful but some more so than others.
“It’s a conversion factor,” he said. “The more herbaceous plants like Swedish Ivy and Dieffenbachia with fleshy rather than wood stems are best. The more foliage per square foot is important.”
Any plant will help improve the oxygen level in one's home, but one could bring any low-light loving native plant into a pot and let it over-winter, said Tacy Fletcher, Board member, Publicity Chair and Newsletter Editor at North Chapter Indiana Native Plant & Wildflower Society (INPAWS), who suggested beautiful slow-light loving plants like wild ginger and polygonum virginianum.
Both are indigenous and might not be available at stores.
“But you can find them outdoors on your property,” said Fletcher. “They don't need any pampering whatsoever. Native plants from the edges of one’s yard can handle being by a cold window all winter and can even handle a little drying out for the forgetful plant-caretaker.”
To get the best possible air purification from house plants, the NASA study recommended that homes 2,000-square-feet or less have a variety of at least 15 houseplants growing in pots six inch or larger.
Bruce Rowe, Supervisory Park Ranger/Public Information Officer for the Indiana Dunes National Lakeshore keeps three spider plants in his house for both decorative and air purifying purposes.
“I'm sure that I would need to have more than three to have a major effect on indoor air quality,” he says, “but I figured every little bit helps.”