Do Plants Really Purify The Air In Your Bedroom?

If you’ve ever heard that having a plant in your room could help to “purify” the air as you sleep, you’ve probably been influenced by a far-reaching NASA study from the ’80s.

This found that indoor plants, like snake plants and aloe vera, could help to get rid of formaldehyde and other volatile organic compounds (VOCs) from the air.

Some have extrapolated from that that placing some plants in your room could help you sleep, though that is not what the original NASA study claimed.

But is that true, and what does “purifying” the air even mean? How many plants would it take to “purify” the air to begin with?

A 2019 meta-analysis of the research into this topic found, well, that potted plants do not improve air quality – given the amount of plants most of us have.

But in theory, they wrote, it could be done – if you used 10-1,000 plants per square metre of your home, room, or office (basically a small jungle) it would “achieve the same [VOC] removal rate that outdoor-to-indoor air exchange already provides in typical buildings”.

Tijana Blanusa, a researcher at the University of Reading and the principal horticultural scientist for the Royal Horticultural Society, told the BBC: “You need an awful lot of plants in very well-lit space to make any measurable impact on the removal of VOCs and many other gases.”

This is even the case for CO2, she added.

Meanwhile, the American Lung Association (ALA) added that the pollen, pests, and dust which houseplants can bring with them can sometimes be “harmful” to indoor air quality.

Nor are they likely to get you to sleep better based on air quality alone.

But, some good news: because their effect on your air quality is so small, there is absolutely no reason to remove your favourite plant from your room based solely on the myth that it “steals” your oxygen.

“Any plant small enough to fit in your bedroom produces far less carbon dioxide than a sleeping human, and is perfectly safe to share a room with,” BBC Science Focus said.

This is not to say that indoor pollution is not a problem. Everything from cooking to cleaning and personal care products can make the air in our homes more harmful, while external pollution can also come inside.

To help combat this, the ALA said your Monstera might not be the answer. Instead, focus on “eliminating pollution sources” like air fresheners, aerosols (spray cans), and dust; ventilating well; and mechanically filtering the air if you need to.

The government also recommends leaving a window open when cooking to remove pollutants like carbon monoxide.