In my zone 6 garden, I. purpurea reseeds vigorously... I have a couple of corners where I let them just go nuts, but I try to keep them out of most of the garden areas.
I've heard that in warmer climates, they can go from thuggish to "conquistador," enough that in some seeds you cannot purchase seeds.
For whatever reason, I haven't tried I. nil in the ground, but it seems like they'd be much less thuggish, both in habit and with regard to reseeding. True?
I do realize sometimes a thug is just what a certain spot needs, and I think reseeding is less of an issue with colder, longer winters. I'm just wondering about choices for areas where thugs would be a bad idea.
What other species or varieties can you suggest that aren't garden thugs?
