Milkweed loss in the US has affected monarch populations so I tried to grow some from free seeds. It wasn’t that easy. I managed to get one scraggly plant. But that was all it took. Three years later, I have a patch. Yes, it attracts monarchs and all sorts of butterflies. The flowers smell luscious–like lilacs. Here’s a Red Admiral (Vanessa atalanta) and maybe a Great Spangled Fritillary (Speyeria cybele). Milkweed contains carenolides, toxic steroids with a bitter taste. Predators that eat insects which have eaten milkweed sicken, throw up and avoid similar insects in the future. Monarchs eat milkweeds as larvae and sequester the poison for their remaining lifespans. Milkweed is poisonous to cattle, pets, and people. The milk or latex is harmful to your eye. How did I not know this? In any case, smell them, enjoy the butterflies, but watch out for milkweeds.