does the milkweed in question, and other milkweeds the Monarch butterflies need, require particular soils, hydration, etc? I was a little disappointed they didn't mention it. It grew where I grew up , but that was all coastal and marshy.
For many, an aggressive, hardy, native plant that is both beautiful and good for insects is welcomed with open arms.
Look for a local extension service or guide on what species are native near you and what types might be good for your soil conditions.
I don't have a backyard, apartment.