My girlfriend's husband bought a couple of seed mats which she lay alongside her house as an experiment of sorts. She lives on top of a hill on the shores of Lake Huron. The wind tunnel along the length of the house promptly tore up the mats and blew most of it away, but she let what emerged grow. What a delight! Lots of poppies, a gaillardia, and this lovely pink specimen that I cannot find anywhere on a plant identification sight. I would love to know what it is! (So would she...)
It has a single, stalk-less leaf for each flower, which emerge along the stem in a long, almost-alternate whorl. Everything is in sets of four...four "petals", four long stamens, four short stamens... There is a fine hairyness to the stems and buds (which are deep green with veins in red...the red spreads over the base of the bud as it matures towards opening.