1. My mother, who was a child in Wimbledon [London] in the 1950s, taught my brother and me various things when we were children in Earls Colne, Essex, in the 1980s …   you can eat hawthorn [Crataegus] leaves, and nasturtiums, and sorrel [Rumex acetosa] leaves [South London Botanical Institute, May 2014].

2.  Nasturtium leaves can be eaten in salads, The bottom of the tube on the flower can be bitten off and the sweet nectar sucked out [Bexleyheath, Kent, October 1998].

3. I was lucky enough to spend part of my childhood in rural Devonshire … some 60 years ago … A rather eccentric great-aunt was regrettably keen on forcing us to eat sandwiches of dandelion leaf if she thought we looked ‘peaky’ … Another remedy entailed the eating of nasturtium flowers, and this, at least, was not unpleasant. What the malady was that this was meant to alleviate I forget, but I vaguely recall that it was for ‘spots’ [Sandon, Hertfordshire, February 1998].

Image: cultivated, Fortune Street Park, London Borough of Islington; May 2014 [as the 2013-14 winter was exceptionally mild nasturtium plants which are usually killed during the winter survived, hence the early flowers].