Not only do they look good, but surprising research is revealing the health benefits of houseplants. In this episode, Michael Mosley explores the science, discovers which houseplants have the biggest impact, and reveals just how many you need in a room to feel the effects. Michael speaks to Dr Tijana Blanusa of the Royal Horticultural Society, to explore the science behind how houseplants can not only improve productivity and cognition at work, they can also improve air quality, helping you literally breathe easier.