Is it true that … houseplants freshen the air in our homes and offices?

If you want to seriously oxygenate your rooms with greenery, you’re going to need a lot of space

‘Plants take in carbon dioxide and release oxygen when they photosynthesise,” says John Tregoning, a professor at Imperial College London and author of Live Forever? A Curious Scientist’s Guide to Wellness, Ageing and Death. “If you’ve got enough of them, they should produce more oxygen than there was initially.”

It’s tempting to think of plants as a kind of natural air filter, cleaning the air in stuffy, poorly ventilated spaces. But the reality is different.