I totally agree with this article! We all need to include Milkweed in our gardens!
I have noticed in my yard is that the male Monarch Butterflies are very territorial. They will fly around "their" garden bed area and try to chase off any other males (or other species of butterfly). But of course, they will woo any female Monarch to their garden. I love watching the males chase each other. I have various garden beds around my yard. I have noticed that males claim different beds. It almost reminds me of male Ruby-throated hummingbirds defending their territory during breeding season. Pretty cool to see the males flying around their garden every day for several weeks until they eventually die.