Ah yes, good point, apparently some of the local nurseries have sprayed their milkweeds with some sort of pesticide, which means you have to keep caterpillars o

Ah yes, good point, apparently some of the local nurseries have sprayed their milkweeds with some sort of pesticide, which means you have to keep caterpillars off them for a year. If you go to a nursery that specializes in natives, that's usually not an issue. In bay area, my favorite nurseries are Watershed and Oaktown Native, and they don't spray. We've actually had a ton of swallowtails this year, which I'll admit are all over my non-native dill. I intend to plant Yampah one of these days, since that's the native version of dill.