Plectritis congesta - a BC and NA west coast native annual, they're often a dark pink colour but the ones that grow wild in my garden are a very light pink.
The fact that Plectritis macrocera is in wildflower seed mixes makes it much more likely to be in Ontario than Plectritis congesta. They sure are similar! I've been reading their descriptions on E-Flora BC and can't find much that distinguishes one from the other. Both can even be light pink in colour. Also, it seems that P. macrocera has been found in BC although very uncommon - and apparently not introduced either. I suggested that @davebyer 's mystery plant was P. congesta based on its similarity to the one I find growing by the 100s in my gardens which I assumed to be P. congesta . . . wouldn't it be funny if mine were P. macrocera?
