Flowers can talk. Red roses say 'I love you'. White lilies offer condolence. Poppies invite us to remember. For thousands of years, humans have used flowers as a language, a short-hand for emotions and meanings. Ancient myths and legends are bursting with flowers and their symbolic meaning; Shakespeare scattered floral clues throughout his plays, knowing his medieval audience could decipher the code; the buttoned-up Victorians used 'floriography' or the secret language of flowers to convey forbidden feelings.Valentine's Day isn't complete without a bunch of red roses, mistletoe invites us to sneak a kiss, daises are the flower of childhood innocence, and daffodils speak of Easter and new life. Oxford University students still wear white carnations for their first exams, a red carnation for their final exam and pink in between.