I was viewing an image of "the Alba Madonna" by Raphael, c. 1510. You can find it in the Google Cultural Institute site in the section for the National Museum of Art. As is common from that period, there are flowers and plants in the scene. Historically, the violets seen in the lower right section would symbolize humility , innocence and purity. In fact, it is said that St Bernard referred to Mary " as the violet of humility".
I have always loved violets. I like the surprise of coming upon them. Here, in New England they typically arrive in the first week of May. They seem to appear after Easter and close to the running of the Kentucky Derby. They are unassuming. They are not grand or flamboyant. Most importantly, their appearance means spring is finally here.