Winter isn't easy on most of us. Piles of ice and snow greet us weekly, and short days make brief periods of sunshine even harder to come by. That, combined with bitterly cold temperatures, means most of us wind up staying inside our well-sealed energy-efficient homes, rather than get outside for fresh air. And that could put your lungs at risk. There are a wide variety of toxic chemicals lurking in your home, and while you can take steps to minimize them, one the most prevalent chemicals in your home isn't easy to get rid of. Formaldehyde, a volatile organic compound that is emitted in low levels by a variety of household building products and furniture, may cause cancer in humans and has been known to trigger asthma attacks and allergic reactions when present in high levels. A common component of glues that hold pressed-wood or particleboard furniture and cabinets together, it's also emitted by natural gas stoves, carpet glues, flooring glues, caulks, sealants, paints, furniture finishes, and the water- and stain-repellent finishes applied to upholstery and clothing.
Government regulations have reduced the amount of formaldehyde that is used in insulation and particleboard furniture, but the sheer number of potential formaldehyde emitters found in the average home makes the chemical difficult to avoid. The good news is, you have a cheap, easy, green tool at your disposal to get rid of it. In 1989, NASA scientists tested a variety of houseplants for their ability to remove formaldehyde from the air, and one of the authors, B.C. Wolverton, later published the findings in a book titled How to Grow Fresh Air (Penguin, 1996).
Following is a list of their top formaldehyde removers, as well as a few other plants that clean the air and may bring a little sunshine into your winter. But before you head to your local greenhouse, ask your friends if they can give you any clippings or root cuttings. Not only are they free, but it's also difficult (if not impossible) to find organically grown houseplants. Greenhouses are breeding grounds for aphids and other plant pests, and as a result, growers commonly use herbicides and fumigants.
Keep reading for the 7 best air-cleaning plants.
#1: Boston fern.
Boston ferns remove more formaldehyde than any other plant. They're also highly efficient at removing other indoor air pollutants, such as benzene and xylene (these are components of gasoline exhaust that can migrate indoors if you have an attached garage). The downside is that they can be finicky. You need to feed them weekly in seasons when they're growing, monthly during the winter, and they like to be watered regularly. Depending on the humidity and moisture levels in your home, you may need to water them or mist their leaves daily. Another good fern for formaldehyde removal is the Kimberley Queen, a larger, broader-leafed fern than the Boston fern. It's also a much better choice if you have particularly dry indoor air, thanks to a high transpiration rate (the rate at which water evaporates from leaves). Wolverton writes that they're "one of the best natural humidifiers of all houseplants tested."
#2: Palm trees.
Palm trees seem particularly good at removing indoor air pollutants, particularly formaldehyde, and fortunately, they're all relatively easy to care for. The best at formaldehyde removal is the Dwarf date palm, which is closest in appearance to the palm trees that remind you of warmer climates (a good cure for the winter blues). But you'll also get clean air with a bamboo palm, areca palm (pictured left), lady palm, or parlor palm. Another plus: Palms like cooler temperatures, in the 60 to 75 degree range, so they force you to be energy efficient and lower your thermostat.
#3: Rubber Plants and "Janet Craigs."
Got a dim office that's just screaming out for cleaner air and a little touch of nature? Try a rubber plant or the dracaena "Janet Craig." Both will tolerate very little sun (though they may grow a little more slowly) and top the list for formaldehyde removers, which is particularly important in offices where most furniture is made from particleboard held together by formaldehyde-based glues. Janet Craigs will tolerate more abuse and neglect than rubber trees, but rubber trees are a little more aesthetically pleasing.
#4: English ivy.
Grown outdoors, English ivy is an invasive species that can damage your home's exterior and tear off your gutters. But bring it inside, and it's an effective formaldehyde remover. Thanks to its ability to climb structures, it's easy to grow as topiary and use as a decorative element in your living spaces. English ivy likes part sun and part shade, so it's a good plant to try indoors, and it's not as temperamental as Boston ferns are. Occasional waterings and mistings during the winter will keep it healthy.
#5: Peace lily.
One of few houseplants that will bloom indoors, the peace lily with its seashell-shaped spathes really will bring a touch of summer into a dreary winter. One of the best plants for removing formaldehyde, it also removes benzene and certain VOCs that are emitted by harsh cleaning products (making it another good office plant, particularly if your maintenance staff doesn't use green cleaners). It also prefers low-light conditions and has a high transpiration rate that will humidify your air. Just be aware that the leaves can be poisonous to pets and children, so peace lily may not be a great choice for new parents or pet owners.
#6: Golden pothos.
Though not high on the list of formaldehyde removers, we've included this plant because you can practically hit it with a hammer and not kill it. It tolerates a lot of neglect and is forgiving when over-watered. And it's still relatively effective at removing air pollutants. For those reasons, it's a great "starter houseplant" for people without much indoor-gardening experience. Golden pothos are often mistakenly sold as philodendrons, which are related plants that are equally good at removing formaldehyde, and almost as forgiving to newbie houseplant tenders.
#7: Flowering air purifiers.
Nothing is better at beating the trifecta of winter blues—dirty air, and lackluster décor—than a flowering houseplant. Florists' mum and Gerbera daisies (pictured) are the best at removing formaldehyde, with tulips not far behind. Of course, nothing worth having comes easy. Flowering plants require more careful watering and feeding, and most prefer cool temperatures (below 65 degrees). Also, unless you're a really good indoor gardener, you have to toss the plants after the flowers die. If you're really dedicated, you can try rooting a new azalea plant this spring in a movable container that you can bring indoors in the fall. Azaleas can be bred to flower all winter, they are great at removing formaldehyde, and they don't have to be tossed out when their flowers fall off.
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