You have probably seen the claim: a few pots of peace lily or snake plant, and your living room air becomes cleaner than a hospital’s. It shows up in listicles, on social media, and in the product descriptions of plenty Read more

A few years ago, I watched a nurse carry a huge bouquet of stargazer lilies out of a patient’s room. The patient was sharing the room with someone who had asthma, and within an hour the scent had filled the Read more

Every spring, a friend of mine buys a big bunch of tulips, puts them on the kitchen table, and then spends the week sneezing. She blames the flowers. Usually she’s wrong. The real trouble is often the oak and birch Read more