Ok that's a little different than I thought. I thought maybe he meant those wild onion things that can have purple flowers. They come from little tiny bulbs.
Both years had a pretty wet June and then we Steined. I think both had it earlier in the month. July 2019 was fairly wet, but I remember lots of near misses with convection.
If it’s what I think it is, I think there was a product my in laws used to kill it. I’ll find out. They got it at Wyman’s garden center on 58 in Hanson.