At my father’s funeral (Ted Ellis, a former Guardian country diarist), we had some sturdy nettles mixed with the flowers on the altar. They also appear as a cure-all in an old family herbal. So I happily endorse Claire Ratinon’s recommendation to leave a patch in your garden (Don’t rush to rip out your nettles – here’s three ways to put them to good use, 28 March). My mother also swore by a few stings to prevent joint pain. She lived to 90.
Mary Stiff
Westwood, Broadclyst, Exeter

I love reading Grace Dent’s reviews, but could she mention how noisy a restaurant is? My friends and I are getting older, and find that more and more restaurants are noisy: hard surfaces, music, tables too close together. It can transform the food and the experience.
Alicia Baker
Highgate, London

The Playfair code (Zoe Williams, 31 March) is still in use among the more arcane crossword community. Azed in the Observer used one in the last few months. There is a very good explanation of how to solve them in Dorothy L Sayers’ Lord Peter Wimsey book Have His Carcase.
Meic Goodyear
Lewes, East Sussex

Given recent events in the US, I am wondering if I’ve misheard the name of the hub at the heart of the White House. Is it actually the Evil Office?
Neil Thomas
Colchester