One of our friends in Oz was laughing that I would voluntarily plant lantana in my yard. It's lovely and dies back every winter. Apparently it is a wild weed down under.
Last summer I let some of the sunflowers that sprung from birdseed grow in my garden. There are lots of native sunflowers, I'm not sure where these come from, they're huge. But they were beneficial in that they attracted some of the pests away from the produce plants. Lace bugs are a problem in my eggplant most years, for example, but last year I found them happily munching sunflowers instead. Perhaps I should say "thank you, Tuscany."
Every summer I pick mustang grapes that grow wild in a copse of hackberry trees across the road from my house. If not this variety, it was another American grape root stock that literally saved the European wine industry after a disease wiped out the native Euro plants. I think the Euro grapes are grafted onto the American roots.
Gardeners who pay attention to their own gardens, make good plant choices, and pay attention to the research (I'm an organic gardener, and there is a LOT of research) are doing just fine.