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Plants Can Clean Inside Air

NASA says the following plants will help clean the air in your home.

In researching ways to clean the air in space stations, NASA (National Aeronautics & Space Administration) discovered that many common household plants and blooming potted plants eliminate significant amounts of harmful airborne gases.

In addition to absorbing the carbon dioxide and releasing oxygen into the air as part of the photosynthesis process, plants also absorb benzene, formaldehyde, and trichloroethylene. These are three of the worst offenders polluting the air of new homes and offices, or those with new furnishings.

Synthetic building materials and furnishings such as carpet, fabrics, laminated counters, plastic-coated wallpaper, and other materials can
"off gas" pollutants into the interior environment. When buildings are well insulated and sealed tightly to conserve heat or air-conditioning, the pollutants are trapped indoors.

If you live in a newer, energy-efficient, tightly sealed home, or if you work in a building with new furnishings or where air feels stale and circulation seems poor, the liberal use of houseplants can help.

Most of the plants on the NASA list evolved in tropical or subtropical forests, where they receive light filtered through branches of taller trees. Because of this, their leaf composition allows them to photosynthesize efficiently under relatively low-light conditions, which in turn allows them to process gases efficiently.

Soil and roots also pay an important role in removing airborne pollutants. Microorganisms in the soil become more adept at using trace amounts of these materials as a food source when exposed to them for longer period of time. Effectiveness can be increased if lower leaves covering the soil are removed so as much soil as possible is in contact with the air.

The best results in air-purification were obtained when small fans pulled air through a charcoal filter in the soil. This cleaned better than foilage alone or in combination with a passive pot of soil. However, even without the fan and filter, houseplants did remove trace pollutants from the air.

The recommendation generated by NASA studies is to use 15 to 18 good sized houseplants in six to eight-inch containers to improve the air quality in an average 1,800 square-foot house. The more vigorously they grow, the better job they'll do.

Although all houseplants probably are beneficial, not all are equally efficient cleaners, and one cannot assume they will remove all harmful pollutants. For example, no plant is of much help in removing tobacco smoke.

But plants do a good enough job of removing air pollutants to cause us to view houseplants as more than just an attractive feature in decorating the interior environment of homes and offices.

Here is a list of indoor air-cleaning plants compiled by NASA:

  • English Ivy (Hederea helix)
  • Spider plant (Chlorophytum comosum)
  • Golden pothos (Epipiremnum aureum)
  • Peace lily (Spathiphyllum "Mauna Loa")
  • Chinese evergreen (Aglaonema modestum)
  • Bamboo or reed plant (Chamaedorea sefritzii)
  • Snake plant (Sansevieria trifasciata)
  • Heartleaf philodendron (Philodendron scandens "oxycardium")
  • Selloum philodendron (Philodendron selloum)
  • Elephant ear philodendron (Philodendron domesticum)
  • Red-edged dracaena (Dracaena marginata)
  • Cornstalk dracaena (Dracaena fragrans Massangeana)
  • Janet Craig dracaena (Dracaena deremensis "Janet Craig")
  • Warneck dracaena (Dracaena deremensis Warneckii)
  • Weeping fig (Ficus benjamina)

    Written by Tommy Kovach - reprinted with permission
    Backwoods Home Magazine, 1257 Siskiyou Blvd, Ashland, OR 97520.
    Backwoods Home's website

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