I quit deadheading my Agastaches around late August or first of September. I want to make sure they make it through the Winter.
I don't collect seeds for that reason. Also, I've learned to wait well into Spring before cutting back the old plant stuff, because of unexpected late Spring freezes/frosts.
When I grew Golden Jubilee, I had a lot of new plants coming up all over where I planted it and now if I plant it, I make sure it doesn't go to seed. Love it for the color of the leaves!
