Myth Debunking - Air purifying plants


Boston Fern


In a world now rife with misinformation, it’s not only news stories we have to look out for. Unfortunately there is a lot of inflated facts and, sometimes complete lies, when it comes to the health benefits of houseplants. We constantly see the wrong information being punted out by sellers, bloggers and news sites every day and often  we have customers coming into the shop convinced that certain plants will cure them of their ailments and vastly improve the air quality in their houses. In this article we here at Mar Mar will attempt to debunk this myth about our green housemates, refine some of the inaccuracies and highlight how plants are still beneficial in many other ways.

We’d like to note: we are not here to crush dreams, but would like to impart at least the small amount of information we’ve gathered, so that we can all move forward with the facts…

Legend has it that certain plant varieties are better for the air quality in our homes than others; many retailers claim that a number of precious greens are even cleansing the atmosphere that surrounds us. When we type ‘air purifying plants’ into search engines, the first results that come up are lists of the 20 best air purifying plants for our homes. Amongst these supposedly purging greens are: Devil’s Ivy / Pothos, Philodendron, Spider Plant, Dracaena / Dragon Tree, Rubber Plant, Boston Fern, Snake Plant, Aloe Vera and Chinese Evergreen, just to name a few.

Philodendron Scandens - Heartleaf 

Headlines of well-known gardening magazines and horticultural websites, as well as hobby gardeners’ personal blogs catch the reader’s attention by claiming for example 'Top ten Houseplants that literally clean the air’, ’12 NASA recommended air-purifying plants that you must have in your house’ and back up their research by often exclusively quoting an over 30 year old study from NASA from the year 1989 (yes, over 30 years old!).

Not only until page two within google search results do we stumble across an article by National Geographic, actually debunking this myth and questioning the trend of shouting out about making your home healthier with plants, when actually this could turn out to be a underhand marketing strategy.
Let’s dig a little deeper, look behind these myths see what we make of these contradictory pieces of information…
A more recent study from 2019, that was conducted by indoor air quality experts, shows that houseplants do improve the air, but not at the scale in which indoor gardeners (us included) actually keep their green housemates. To put things in perspective; for plants to truly cleanse the air in our offices or houses, equating to the improvement of air quality from opening a window for one hour, we would need so, so many, that there actually wouldn’t be much space left for us or anything else like furniture and home decor.


Philodendron Squamiferum


What does that mean exactly? So, for an approximately 46 square metre apartment, we would need around five thousand efficient varieties of VOC-filtering houseplants for the greenery to be able to purify the air that surrounds us. For a 10 square metre office we would need around a thousand plants. That sounds like a jungle to us - mad, isn’t it?!
It would be unfair to accuse everyone of lying about air purification as, on one hand it is true, but it is not achievable in 99.9% of homes. It seems, some out there are conveniently leaving out this information to inflate sales. Crazy, that so many plant favourites are still being marketed and sold to keen customers as healthy purifiers for our offices and homes…

Just to clarify, here are some bullet points of so-called “facts” that have been posted by sellers online. This is simply not true and a bit alarming to see, as plant owners might believe that they can rely on this information to heal their health conditions. So to clarify: houseplants in normal quantities (less than five thousand in a small apartment) do not:

Improve our immune system
Help with COPD and other respiratory illnesses
Absorb airborne toxins
Improve dry skin
Increase humidity 

We have not set out to strip any enjoyment from keeping houseplants, because they do have wonderful other beneficial effects. Even if they don’t clean the air to the extent that we might have hoped they would, they absolutely make our surroundings feel more natural and have the potential to contribute to show stopping interior designs. Also, like with anything homemade or homegrown, for example some fresh herbs on the windowsill or carrots harvested from a container in our back yards, our green housemates have the effect and talent to improve our moods and mental states of mind by bringing the outdoor world into our homes.

Chlorophytum Variegata - Spider Plant

The quick fix option for air purified rooms: Crack a window open, buy a HEPA filter and a humidifier and enjoy the proven psychological benefits of houseplants for increased positivity, creativity, purpose and happiness.





Cummings, B.; Waring M. (2019): Potted plants do not improve indoor air quality: a review and analysis of reported VOC removal efficiencies. Journal of Exposure Science & Environmental Epidemiology. (30) p. 253–261.

Gibbons, S. (2019): Which houseplants should you buy to purify air? None of them. National Geographic. 

Meyer, R. (2019): A Popular Benefit of Houseplants Is a Myth. The Atlantic. 

Wong, J. (2020): How many house plants do you need to clean the air in a small flat? New Scientist.