Probably Dame's Rocket....

It might be purple loosestrife (very invasive), but that's only a guess.

-Audric

Mine are blooming in the gardens at this time. Dame's Rocket it is! Love the smell!!
Nicole.

I have a few as well..Now I think maybe I have not identified them...I have some long thin bursting with purple flowers all along the arrow like stem...maybe those are Dames Rocket. the ones I thought were Dames Rocket..are tall with clusters of small flowers bursting out of a sunburst of stems..they, are white, pink, or pale purple?? now I have to look up what they are... I thought that most along the highways were Purple Loostrife, as Audric suggests..!martha/zucchini

Its is dame's rocket (hestpris) and one of my favourite flowers! I've had them in my garden for years, one purple and one white. They grow into a lovely large clump and, if you cut the flowers off after blooming, they will rebloom and so last most of the summer. Fabulous perennial! You can buy them at a lot of garden centers, I got mine at the side of the road.

Check out the flowers closely. If the have four or five little red "stems" for lack of a better word, they could be Viper's Bugloss. They are bloomimg right now all over Manitoulin Island and farther north into Kirkland Lake and Timmins, Ontario