Need help identifying a wild flower in NJ?

I've been dedicating quite a bit of time to turning portions of my yard into a perennial garden. I purchased quite a few typical garden plants but would like to include some wild plants indigenous to the area. While driving up to my parents' house yesterday (Warren County), I saw a plethora of purple, lavender and white flowers growing in fields and along the roadsides. They are beautiful and I would love to know what they are. If anyone is familiar with Land of Make Believe, there are a ton of them growing in the field across the road. If anyone has any clue as to what they are, please let me know. Thanks!