I've got another one: Cotoneaster? My mother called it "ka-toe-nee-ASS-ter" but my neighbor in Salt Lake surprised me one day by referring to it as "Cotton Easter".
I'm on board with cam-PAN-yoo-la. As for Agastache, the last syllable is the same as mustache. I think -ach is pronounced "ak" but -ache should be "ash" . . . when it's not a head ache.
