These violets are Bird’s Foot Violets (Viola pedata). I bought them because they are supposed to be host plants for the Regal Fritillary (Speyeria idalia). The last I heard, it is now believed that they are more likely to use the Prairie Violet as a host plant instead. Regal Fritillaries are relatively rare. One subspecies is, or nearly is, on the endangered species list. I’ve never seen one and it is unlikely that one will ever fly into my garden where I live. Both of these violets (Bird’s Food and Prairie) are native to North American. At one time, when much of the country was covered with native prairies and woodlands, these violets were growing all over the place. The Regal Fritillary was also a common butterfly then. But now, with so much native habitat destruction – very few prairies remain – the Regal Fritillary is seldom seen.
These flowers come in two different colors, here is a photo of one of the other color, taken a few days later: