Hello: This white June flowering perennial was given to my mom from an older relative close to fifty years ago. I remember helping her plant it. I now have a piece of it in my urban garden (SW Ontario). It flowers reliably every year and is slowly spreading a little bit each season. The very strong sent is one you like or don't like. After fifty years at the farm, growing against a hot east wall, it had spread to be an 8' x 3' patch. Once it flowers the foliage stays low to the ground for the season, very nondescript.

This is my third attempt to try to identify this plant. Please have a look at the pics. Thanks for any leads.