"They were only playing Leapfrog.

Must watch more closely next year.
I know Liatris is odd in that it flowers from the top down, as opposed to t'other way like any normal, sensible, plant.
BUT
I had never noticed Verbascum appears to play Leapfrog up the stem by flowering in clumps on the way up. If it continues I'll find out this year, if it doesn't it'll be next year.