Houseplants are indoor clean air machines
November 10, 2011
  • /Crop Sciences
Today's tightly sealed homes are less drafty and more energy efficient, but that tightness can also mean that more pollutants are trapped indoors. University of Illinois Extension horticulture educator Greg Stack said houseplants can help make the air inside healthier by absorbing pollutants.

"Fewer drafts and energy efficiency are good, but today's new homes and upgraded older homes have become so tight that natural air exchange is greatly reduced or virtually eliminated, trapping more indoor air pollutants such as formaldehydes, benzenes and other gases from carpeting, paints, laminates, furniture and other man-made materials," said Stack. Stack quoted a recent study conducted by NASA that suggests houseplants can help improve indoor air quality.

"NASA has been researching ways to clean up the air in space stations and make the environment suitable for humans to live and work," Stack said. "While dong this research, NASA found that many common houseplants can do some interesting things when it comes to cleaning up indoor air pollution. "Plants absorb carbon dioxide and give off oxygen during the normal process of photosynthesis," Stack explained "They are also very efficient at absorbing things like benzene, formaldehyde and lots of other air pollutants associated with today's energy-efficient, 'tight' homes. They not only clean the air but also help interior humidity."

Stack said many of the houseplants NASA has found to be particularly good at cleaning the air are also houseplants that are commonly suggested for low-light interior spaces because they can adapt and grow very well inside the home. NASA's recommendations start with a plant almost everyone seems to have, Stack said, the spider plant. "We see it in baskets, on top of tables, and especially in dorm rooms."

The peace lily or Spathiphyllum is a durable houseplant and can grow to an impressive size indoors and provide flowers as well, Stack said. The Pothos with its variegated leaves makes a nice basket plant and Philodendron selloem, or split-leaf philodendron, has large impressive leaves. Dracaena or corn plant with its narrow corn-like leaves provides a nice vertical accent. The cultivars that work very well are Massangeana and Janet Craig. And two very common, widely used house plants, snake plant and weeping fig, round out the list.

"Weeping fig can very easily become an indoor tree," he said.

Stack said that this list of plants is great because they are all readily available and commonly found at garden centers, home improvement stores, and florists. They aren't exotic.

NASA's studies also suggest a 6- to 8-inch-size house plant (pot size) is capable of cleaning the air in about 100 square feet of living space.

"In order to keep your clean air machine working efficiently, it is a good idea to keep the leaves clean," he said. "Occasionally wiping the leaves with a damp cloth to remove dust and debris will make sure the plant is in top operating form."