Toni, you're not alone in your sentiments; I just recently read some similar words about the horehound plant. I think it was someone from Southern California, so probably on the dry side (as the song goes, 'It never rains in California').
It's supposed to be invasive here in Texas but I haven't noticed. When we had drought conditions two summers in a row, the horehound was struggling to survive so I moved it into part shade. It's doing well.
I grew mine on purpose
after much effort. It's the medicinal value that draws me to this herb. And the fond memories. I procrastinated and didn't make my horehound candy last year. I'm looking forward to making it this year - for sure!!
According to this website, horehound germinates in the wild with sufficient rain in autumn and followup rain in winter and spring. It also says that seedlings don't survive low rainfall in spring and summer ~ read the entire info here ~
http://www.texasinvasives.org/...
