Houseplants are the latest word in household cleaning.
Research now shows that houseplants play an important role in cleaning the air we breath, both indoors and out.
Plants produce their own food through a process called photosynthesis. This means they take in carbon dioxide from the atmosphere and release oxygen. Photosynthesis “cleans” our air by absorbing carbon dioxide and by taking in certain other pollutants, as well.
Even in huge, busy cities, outdoor air is cleaner and preferable to indoor air. Why is that? One reason is that trees and plants are constantly cleaning the air outside. This suggests that the eco-minded homeowner or office dweller should go out and buy some plants – but which ones? With all the hype of “going green”, every plant on the market is being promoted as an air purifier!
A team of National Aeronautics and Space Administration (NASA) researchers lead by Dr. Bill Wolverton tested the effect of fifteen house plants on three pollutants known to be present in spacecrafts. These same three pollutants–benzene, formaldehyde and trichloroethylene–are present in homes and office buildings. They occur because they are emitted from furnishings, office equipment and some building materials.
Under controlled conditions, in the NASA study, certain houseplants were found to remove as much as 87 percent of indoor air pollutants within 24 hours.
Until recently, indoor air pollution was not considered a health threat; most homes and public buildings leaked so much that air often was replaced every couple of hours. But during the 1970’s, after energy shortages occurred, more and more of us began to insulate our houses and office buildings to conserve energy and lower heating and cooling costs. As a result, indoor air might linger for five hours or more allowing pollutants to accumulate.
Researchers are just beginning to understand how indoor pollutants such as cigarette smoke, for example, can harm humans. Effects range from skin and eye irritations to headaches and allergies. Some of the pollutants may be carcinogenic.
Houseplants are a great way to beautify a room: their colorful leaves and interesting shapes often provide the perfect natural counterpoint to man-made furniture and structures. But houseplants are more than just a bunch of pretty faces. According to research, they can help improve indoor air quality by removing pollutants known as volatile organic compounds (VOCs).
Plants’ ability to help us breathe easier indoors was first demonstrated in a two-year study conducted by NASA in the late 1980s. At the time, the agency was looking for houseplants to help clean the air in space facilities. The study examined the ability of 15 houseplants to remove three common indoor pollutants — the VOCs benzene, formaldehyde and trichloroethylene — from the air. Benzene is emitted from paints, synthetic fibers and plastics, among other sources. Formaldehyde is released from many sources, including foam insulation and plywood, and sources of trichloroethylene emissions include paints and varnishes.
Below is a list of household plants that were found to be effective at removing VOCs in the NASA study:
Areca palm tree
NASA Purifying Score: 8.5
The top air purifying plant as ranked by NASA’s study is the Areca palm tree. Dubbed “the most efficient air humidifier” by MetaEfficient, the Areca can be counted on to keep your home or office moist during dry times and continuously remove chemical toxins from the air. During winter time, it can literally replace the use of electric humidifiers altogether!
Lady palm (or Rhapis excelsa.)
NASA Purifying Score: 8.5
Neck and neck with the Areca palm tree for NASA’s top-ranked air purifying plant is the Lady palm (or Rhapis excelsa.) A versatile plant, the lady can be kept in dry or humid climates (anywhere from 20-100 degrees Fahrenheit) and is fiercely resistant to most types of plant insects.
Date palm tree (or Phoenix roebelinii)
NASA Purifying Score: 7.8
While it doesn’t rank as high on the purifying scale as its 3 palm cousins, make no mistake: the Date palm tree (or Phoenix roebelinii) is still a very effective and elegant-looking way to both liven up the look of a room and lower the concentration of chemical toxins floating around in the air.
Peace lily (Spathiphyllum wallisii) –
NASA Purifying Score: 7.5
All that’s needed to keep and maintain this beautiful indoor air toxin killer is plenty of water and a modest amount of sunlight. Preserve these conditions at all time and you’ve got yourself an all-natural air purifier that will remain hard at work 24/7!
This plant, which does best when placed in a shady spot, can remove both benzene and trichloroethylene. It is poisonous, so keep out of the reach of children and pets. Also, avoid over watering.
NASA Purifying Score: 7.7
The ficus alii (or Ficus macleilandii) is not as potent in its toxin-removing prowess as, say, the rubber plant, but it is still a fine addition to any home or office where clean air is lacking. While they are not terrible difficult to care for, Plant Care Guru warns that gloves should be worn while handling the plant if you have latex allergies.
Golden pothos (Scindapsus aures) –
This vine proved adept at filtering formaldehyde. It can be placed virtually anywhere in a home and requires a thorough watering about once a week.
NASA Purifying Score: 7.8
If the air where you live has gotten stale and dry, English ivy (orHedera helix) might be just the ticket! WebMD describes the effervescent plant as “a fix for allergies“, noting that 60% of airborne mold in the room vanished just 6 hours after English ivy was brought in. Ditto for 58% if airborne feces! Those with asthma, allergies, or the desire to breath cleaner, fresher air would do well to give English ivy a shot!
Effective at removing formaldehyde, this plant thrives in cool, moist air. It too is poisonous, so keep it away from pets and children.
Chrysanthemum (Chrysantheium morifolium) –
This plant, which can produce wonderfully bright-colored flowers, can filter both benzene and formaldehyde. It does best in direct sunlight.
Gerbera daisy (Gerbera jamesonii) –
Just like the chrysanthemum, this plant features bright flowers and requires lots of sunlight. It removes both benzene and trichloroethylene.
Mother-in-law’s tongue (Sansevieria trifasciata ‘Laurentii’) –
This hardy plant (at left) filters formaldehyde and doesn’t require a lot of maintenance.
NASA Purifying Score: 8.4
Just a notch below the top 2 air purifying palms is the Bamboo palm (or Chamaedorea seifrizii.) Featured prominently in CasaSugar.com’s“Plants That Purify” series, the Bamboo palm thrives when kept moist (but not wet) in indirect sunlight. Provided these conditions are kept stable, the Bamboo palm can be counted on to purify the indoor air of anywhere you happen to be.
The bamboo palm is effective at removing formaldehyde. Its soil should be kept moist, and it needs to be placed in indirect sunlight.
Azalea (Rhododendron simsii) –
Effective at filtering formaldehyde, this popular plant does best in a cool environment (around 65 degrees) and out of direct sunlight.
Red-edge dracaena (Dracaena marginata) –
NASA Purifying Score: 7.8
The Dracaena (or Dracaena deremensis) places fifth on NASA’s ranking with a 7.8 score. Bright and radiant, the Dracaena (nicknamed “Janet Craig”) will go to work purifying the air in your home or office as soon as it is brought into the room!
Capable of growing up to 15 feet in height, this household plant is a good multi-tasker: it can remove both benzene and trichloroethylene. It is best suited for a temperature of 75 degrees or so.
Spider plant (Chlorophytum comosum)
This plant filters formaldehyde and doesn’t need a lot of upkeep.
Boston Fern (or Nephrolepis exalta.)
ASA Purifying Score: 7.5
Ninth on NASA’s ranking of top air purifying plants is the ever-popular Boston Fern (or Nephrolepis exalta.) Cool and relaxing, the Boston Fern has been called the “most efficient filtering plant” by MetaEfficient.com for its time-tested ability to expel mold and toxins from indoor air. Plus, it’s sure to make any home or office more forest-like!
It takes a village
To establish an effective plant-based air-pollution control system, you’ll need more than one plant in your home or office. The NASA study recommends using one potted plant per 100 square feet of home or office space. The plants also should be in containers with diameters of six to eight inches, the study urges.
With the advent of more energy-efficient homes and offices, which often reduce the flow of air between the inside and outside of a building, it makes more sense than ever to be concerned about indoor air pollution. By using the plants listed above, you can help create a healthy environment in your house or place of work.