Recently, I noticed a rather irritating poster on the Underground proclaiming: ‘You never forget your first time.’ It was an advertisement for a villa holiday company – bizarrely – but the irritation I felt (since I am not annoyed by villa holidays per se) had to do with the too obvious double entendre. In fact, one does not forget the first time that one does quite a lot of things – seeing one’s name in print, for instance, or walking along Striding Edge, that most vertiginous of paths on to the top of Helvellyn – and certainly I have never forgotten the first time I read a gardening book.