Will Ageratum Self-Sow If Not Deadheaded

Question From: E. Hildner - MICHIGAN
Q: I have never grown ageratum that are so lush without special attention. I am wondering,would I be lucky enough to have them self-sow if I don't deadhead? I live in mid Michigan and the winters can be pretty harsh.

A: So sorry, they do reseed in Michigan. Best And Happy Yardening, Nancy