I would love to plant many of these plants, but plants like herbs, Black Eyed Susan, etc. tend to take over the garden. I planted oregano in my garden and ended up having to pull it out because it was taking over. I have it in a barrel type pot now on my deck, but the butterflies and hummingbirds don't come that close. Short of putting barrels in the yard, which would not look nice to me, how to you contain these plants? My friend has Black Eyed Susan's and complains they seed themselves all over her yard to the point she doesn't like them. I want to plant them (she gave me some roots), but now I'm scared to plant them in the ground for the same reason. What do you recommend?