With our national sport back up and running, it’s easy to forget that other Canadian obsession we routinely like to participate in during the coldest months of the year – and it has nothing to do with skates, sticks, pucks and Don Cherry.
The game of keeping old man winter and his frosty air out of our homes has been a nationwide preoccupation for as long as I can remember, although these days, modern insulation, better construction materials and government incentives encouraging us to send those drafty old windows to the dumpster have made houses more airtight than ever. Unfortunately, this energy efficiency has come at a price, and the lack of natural air exchange that comes with hermetically sealed windows and doors has meant an alarming number of nasty pollutants are trapped within our homes.
These unnatural gases – some with terrifying names like formaldehyde, benzene and trichloroethylene – are referred to as volatile organic compounds (VOC) and they are regularly emitted from such common household items as cleaning products, insulation, freshly painted walls and flexible plastic products like children’s toys, shower curtains and electronic equipment. But, thanks to research by NASA more than 30 years ago, houseplants are now regarded as one of the most effective weapons that can be used to combat indoor air pollution.
Back in the 80s, when the International Space Station was little more than a bucket of titanium nuts and bolts spread around assembly plants in the United States and the Soviet Union, NASA decided to embark on a study to investigate the possibility of using plants as living air scrubbers for future space colonization. In addition to the obvious benefit of taking in carbon dioxide and releasing oxygen as a by product which occurs during the normal photosynthetic process, scientists confirmed that some popular tropicals also have the ability to process and filter large quantities of toxic chemicals when exposed to high levels of the stuff in sealed test chambers. The plants perform this magical feat by absorbing the offending gases through stomata on their leaf surfaces and transporting the substances through their circulatory system. Eventually the material is deposited into the soil surrounding the root zone where naturally occurring microbes quickly mobilize to neutralize and render the toxins inert.
Of course not all plants are equal in their ability to dispose of pollutants and some have to be installed in large numbers to have any measurable effect on air quality. So in order to avoid having to fill your house with so much greenery that you need a machete to find the fridge, here are a few examples of common houseplants that are proven top performers.
Peace Lily (Spathiphyllum) – A large-leaf plant suitable for semi-shade and partially sunny areas of the home that has the ability to absorb a wide variety of chemicals like acetone, formaldehyde, and trichloroethelyne. Given the right growing conditions, you may also be treated to beautiful white spathes that appear sporadically throughout the cold winter months.
Fig (Ficus sp.) – Both the small leaf ‘benjamina’ as well as the larger leaved ‘elastica’ (also known as the rubber plant) are excellent in cleaning the air of formaldehyde, which is probably the most common household pollutant found in our homes.
Gerbera Daisy (Gerbera spp.) – If you want a serving of flowers with your air purifier, this is the plant for you, although they need bright light and cool temperatures to bloom indoors. The small size of gerbera also means you may need more than one for effective removal of airborne pollutants.
Potted mums and phalaenopsis orchids make good flowering alternatives.
Palm – Most varieties are champions when it comes to indoor air purification, especially areca and bamboo palms whose large size make them popular in malls and office buildings. However, they can be fussy and hard to grow in homes that can’t provide the quantity of light and reasonable levels of humidity to keep them happy during the winter months.
Dracaena (Dracaena spp.) – If my 30-year-old specimen is any indication, they are not only versatile and attractive, but almost indestructible as well. A large number of draceana varieties are available and all are highly effective at filtering indoor pollutants. They are low maintenance and most will grow well in full sun to semi-shaded areas of the home.
In addition to the species mentioned above, there are a large number of other tropicals like philodendron, spider plants and ferns that are well-known for their ability to remove nasty chemicals from the air. Most are readily available during the winter months at nurseries, big box stores and even supermarkets, and with an increased awareness of the benefits plants can have on closed environments, many retailers regularly attach labels to certain species to promote their air cleaning capabilities.
Steven Chadwick is a professional gardener/horticulturist, and longtime Beach resident