Always keen to link my reading with other things, I just happened to have taken some pictures of iris when the flower cropped up - and clearly with a great deal of significance - in Nicola Upson's An Expert in Murder (and more on the book here).
"The flowers which he had believed to be of a uniform deep lilac with a single splash of yellow were, in fact, a complex blend of tones and colours, each slightly different to the next. 'Did you know it's supposed to be the flower of chivalry?' she asked. 'Three petals - one for faith, one for wisdom, and one for valour.'"
Regardless of the flower's meaning, isn't its colour beautiful?