Ask anyone what a red rose means and you will get the same answer: love. That answer is old. The floral dictionaries of the nineteenth century, which gave every flower a sentiment so that a posy could carry a message, put the rose at the centre of the vocabulary of love.

Look at a real one, though, and it gets more particular. Kate Greenaway's Language of Flowers, published by Routledge in 1884 and now free on Project Gutenberg, lists more than thirty roses. The plain "Rose" is "Love". A red rosebud is "Pure and lovely". But a deep red rose is "Bashful shame", which is not what most people mean when they hand one over.

That gap is normal for this subject. The historian Beverly Seaton, in The Language of Flowers: A History (1995), shows that there was no single Victorian code: the meanings differed from book to book and from country to country. The Chicago History Museum adds that many meanings were pulled, fairly arbitrarily, from poetry or from a plant's medicinal uses. So when a modern list tells you exactly what a red rose "means", it is choosing one book over another, or inventing.

The red rose also carries meanings that have nothing to do with romance. It was a badge of the House of Lancaster in the fifteenth-century civil wars that were later called the Wars of the Roses, a name that only caught on after Walter Scott's 1829 novel Anne of Geierstein. Greenaway's list nods to this too: "York and Lancaster" roses mean "War".