The Air Cleaning Experiments
Most people have heard at some point that house plants are good for your healthbecause they can clean, filter and purify the air of various toxins and pollutants. A lot of people know that this has been proved by science, although most people don’t know about the actual studies or which plants are best for the job.
Humans have always “known” plants did more than provide food for us or look good, but there was no real science to support this idea. It wasn’t untilThe National Aeronautics and Space Administration (NASA) began to think about future life-support systems so humans could live on the moon and other planets that the ability of plants to filter and purify the air was exposed in full detail.
NASA proposed that if humans traveled to inhospitable planets then small biospheres would need to exist in order to support them, much like a spacecraft provides a suitable environment for its passengers as they travel through space. The issue however was that at the time spacecrafts could only be used for short periods due to the quick build up volatile organic chemicals, coming both from the people themselves as well as various equipment and machinery used on the craft.
Between 1980 and 1984 NASA proved plants in sealed test chambers that were exposed to volatile organic chemicals could remove them from the air. Including formaldehyde which is found in, or used to produce, a multitude of everyday products, from fabrics and furniture to tobacco smoke and gas stoves. Numerous scientific studies have shown it is dangerous to human health, the US National Toxicology Program in 2011 even went as far as to label it as a “human carcinogen“. In 1984 people were very excited by NASA’s findings and as a result they funded significant research looking at house plants and their air purifying abilities.
Dr Bill Wolverton was one of the scientists brought on board to help research and study the effects of houseplants on air quality in contained spaces and produced some of the most popular and commonly referenced research papers about the topic.
If you want to read more about Dr Wolverton’s work, the experiments themselves, or better understand how he formulated his ranking we have provided an Amazon link below to his book.
The List of 50 Plants
The list is ranked in order of plant effectiveness in a typical home according to Dr Wolverton. So the 1st plant in the list (Areca Palm) is the most effective and the 50th (Kalanchoe) is the least.
(Some of the plants are links because they have a page on OurHousePlants.com. As our site grows more will become links!).
- Areca Palm (Chrysalidocarpus lutescens)
- Lady Palm (Rhapis excelsa)
- Bamboo Palm (Chamaedorea seifrizii)
- Rubber Plant (Ficus robusta)
- Deacaena “Janet Craig” (Dracaena dermensis)
- English Ivy (Hedera helix)
- Dwarf Date Palm (Phoenix roebelenii)
- Ficus “Alii” (Ficus macleilandii)
- Boston Fern (Nephrolepis exaltata “Bostoniensis”)
- Peace Lily (Spathiphyllum)
- Corn Plant (Dracaena fragrans)
- Golden Pothos (Epipremnum aureum)
- Kimberley Queen Fern (Nephrolepis obliterata)
- Pot Mum (Chrysanthemum morifolium)
- Gerbera Daisy (Gerbera jamesonii)
- Dracaena “Warneckei” (Dracaena dermensis)
- Dragon Tree (Dracaena marginata)
- Red Emerald Philodendron (Philodendron erubescens)
- Syngonium (Syngonium podophyllum)
- Dumb Cane (Dieffenbachia “Exotica Compacta”)
- Parlor Palm (Chamaedorea elegans)
- Weeping Fig (Ficus benjamina)
- Schefflera / Umbrella Plant (Schefflera arboricola)
- Wax Begonia (Begonia Semperflorens)
- Lacy Tree Philodendron (Philodendron selloum)
- Heart-Leaf Philodendron (Philodendron Oxycardium)
- Snake plant / Mother-in-Law’s Tongue (Sansevieria trifasciata / laurentii
- Dumb Cane (Dieffenbachia camilla)
- Elephant Ear Philodendron (Philodendron domesticum / tuxla)
- Norfolk Island Pine (Araucaria heterophylla)
- King of Hearts (Homalomena wallisii)
- Prayer Plant (Maranta leuconeura “Kerchoveann”)
- Dwarf Banana (Musa cavendishii)
- Christmas Cactus (Schlumbergera buckleyi)
- Easter Cactus (Schlumbergera gaertneri)
- Oakleaf Ivy (Cissus rhombifolia “Ellen Danika”)
- Lily Turk (Liriope spicata)
- Dendrobium Orchid (Dendrobium)
- Spider Plant (Chlorophytum comosum)
- Chinese Evergreen (Aglaonema crispum “Silver Queen”)
- Anthurium (Anthurium andraeanum)
- Croton (Codiaeum variegatum pictum)
- Poinsettia (Euphorbia pulcherrima)
- Dwarf Azalea (Rhodedendron simsii “Compacta”)
- Peacock Plant (Calthea makoyana)
- Aloe Vera (Aloe barbadensis)
- Cyclamen (Cyclamen persicum)
- Urn Plant (Aechmea fasciata)
- Moth Orchid (Phalaenopsis)
- Kalanchoe (Kalanchoe blossfeldiana)
Not found your particular house plant on that list? It’s really important to remember that Wolverton’s experiments focused on common house plants at the time. There would be no point putting in a fantastic air cleaning house plant if no one had ever heard of it, or more importantly actually wanted to have it in their homes. The studies were also done in the late 1980’s before certain plants like the ZZ Plant and Yuccahad even become house plants in their own right and therefore weren’t part of the experiments either. This means a lot of modern house plants around today aren’t on the list.
However even if some of your own plants didn’t make it into the list there is no reason to see this as a negative. Almost all plants on the planet have an air cleaning ability, although it’s true some are better adapted to deal with certain toxins, pollution and putting moisture back into the air than others.
There may be certain plants ranking high on the list you really can’t stand and others which you love but are lower down. Our opinion is that you should select plants for your home or office that you actually enjoy and like. The list will simply illustrate that if you own (or spend time around) any of the plants above then there is hard scientific proof that they will clean the air in your home or office and have the official stamp that they “are good for your health” as a result.
Which plants do you have? Would you consider buying any from the list as a consequence of reading this? Do you agree with Dr Wolverton’s findings? Let us know in the comments below!