It is no secret that houseplants make wonderful additions to any indoor environment, but it was only recently understood that their beneficial influence extends far beyond their beauty. Recent studies undertaken by NASA have shown that houseplants are effective at significantly improving indoor air quality by producing oxygen and decreasing harmful pollutants. Houseplants are generally of tropical origins, growing in the shady understory of tropical forests. This means they thrive in low light and must be incredibly effective at processing gasses necessary to photosynthesise, which makes them both well-suited to indoor environments and naturally able to remove harmful chemicals from the air.
Sansevieria, also called snake plant or mother-in-law's tongue, is a common houseplant found at most garden supply stores. The plant, although not rare, is remarkable in its ability to convert large amounts of carbon dioxide into oxygen, as well as its effectiveness in removing certain indoor pollutants from the air. Studied extensively by NASA scientist B.C. Wolverton and environmental scientist Kamal Meattle, sansevieria is shown to filter out benzene, which is a chemical linked to Sick Building Syndrome (SBS). Sansevieria is most effective at producing oxygen at night, making it a perfect plant to keep in the bedroom.
Dracaena is among the most popular houseplants, with over 40 varieties of diverse shapes and sizes. The NASA study undertaken by B.C. Wolverton showed that three varieties were particularly effective at producing oxygen and alleviating indoor air pollutants: Dracaena fragrans, Dracaena deremensis and Dracaena marginata. According to Dr. Wolverton's study, dracaena is particularly effective at filtering formaldehyde out of the air, which is an irritant and has potential cancer-causing properties.
Three varieties of philodendron were used in Dr. B.C. Wolverton's NASA study concerning the effects of houseplants on indoor air quality, and all were shown to significantly improve the oxygen content of air in enclosed spaces: Philodendron scandens, Philodendron domesticum and Philodendron selloum. All three varieties of philodendron used in the study were remarkable for their efficient production of oxygen, particularly in areas of low light, making them ideal for offices and bathrooms.
Areca palm is a tall, graceful variety of houseplant that was utilised in Dr. Kamal Meattle's study of the healthful effects of houseplants on work environments. His study showed that areca palms are among the most effective plants at oxygenating small, enclosed areas. To receive maximum benefits, it is recommended that four shoulder-high plants be provided per person.
Money plant is a delicate houseplant that is often sold with a braided stem and hand-shaped leaves. Rumoured to be good luck, new evidence supporting the plant's efficacy at removing harmful chemicals from the air might lend credence to that popular belief. Of the plants utilised in Kamal Meattle's study, money plant showed the most promise in removing formaldehyde and other volatile organic compounds (VOCs) from the air.
spider in a basket image by Joann Cooper from Fotolia.com
Among the other plants proven to be effective at oxygenating air in the NASA study were English ivy, spider plant, ficus, chrysanthemum, devil's ivy and gerber daisy, which were all proven to have a positive effect on the oxygen content and chemical content in indoor air.
- "Foliage Plants for Improving Indoor Air Quality"; B.C. Wolverton, Ph.D.; 1988
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