You should only be planting native species whatever they are for your specific area.

I think majority of places are beyond that point. I’ve found that planting whatever works, even if incrementally, should work. I plant natives, but for natives alone won’t work unless my entire neighborhood does so. So you supplement with non natives that provide something. Milkweed will help with the butterfly larvae but what do you feed the butterflies? Something that’s long blooming and nectar rich. So I let the red valerian that grows like an invasive weed in all conditions, remain blooming in my yard for months at a stretch.

The “butterfly bush” is native to China. Milkweed is native to North America.

Milkweed is the only one that can feed the Monarch at all stages of its life, from larva to caterpillar to butterfly. When people plant butterfly bushes, it “tricks” the butterfly (or at least crowds out better options) into laying eggs where the larvae will ultimately die of starvation.