Episode 75: do houseplants clean the air?

Spathiphyllums (peace lilies) are one of the best plants for removing CO2 and pollutants from the air. Photograph Curtis Gubb.

Spathiphyllums (peace lilies) are one of the best plants for removing CO2 and pollutants from the air. Photograph Curtis Gubb.

You’ve read the headlines, but do houseplants really clean the air in your house? A Nasa study from decades ago is the oft-cited authority on the subject, but surely there must be some more recent research into the topic?

Thankfully, the answer is yes. Curtis Gubb is in the final year of a PhD at the University of Birmingham. He’s working on a project to discover whether houseplants really do have a positive effect on air quality, working in partnership with the RHS. I chatted to him about his research findings so far, and found out a bit more about the truth behind the headlines on air quality and houseplants as a route to healthy skin.

Resources for this episode are below…

Curtis Gubb in the lab with some of his plants.

Curtis Gubb in the lab with some of his plants.

Question of the week

Alexis wanted a small fern for a terrarium designed as a gift for a relative. The trouble with most suggestions for terrarium ferns is that they are species that will soon outgrow the average enclosed glass space. I suggest a few alternatives that are slow growing and will stay smallish - around 15-20cm tall.

  • Hemionitis arifolia or the heart leaf fern will only reach around 15cm and has leathery, heart-shaped leaves. It enjoys constant moisture so it’s a perfect terrarium subject. It’s fairly widely available (unlike some of my other suggestions).

  • The eyelash fern (Actiniopteris) is another dwarf fern that would work really well, it likes things a little less moist than the other ferns mentioned here though.

  • Tectaria zeilanica or the oakleaf fern is a bit tricky to get hold of but rather nice and slow growing too.

  • And finally, Biophytum sensitivum isn’t a fern but has somewhat ‘ferny’ qualities - although it also looks a bit like a teeny palm tree! It does really well in terrariums, too (If you remember James Wong talked about these plants in his globe-shaped terrarium back in episode 55.)

Want to ask me a question? Tweet @janeperrone, leave a message on my Facebook page or email ontheledgepodcast@gmail.com.

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This week's show featured Roll Jordan Roll by the Joy Drops, An Instrument the Boy Called Happy Day Gokarna by Samuel Corwin and Oh Mallory by Josh Woodward, all licensed under Creative Commons. Ad music is Dill Pickles by The Heftone Banjo Orchestra.