I have Milkweeds in my garden for the Monarch caterpillers and fennel, parsly and dill for the swallowtail caterpillers. But mostly I find that the flowers here that attract lots of both are butterfly bush, zinnias and mexican sunflowers. In fact all three are great for attracting both butterflys and hummingbirds. Best flowering shrub would be Butterfly bush and I have five of them. Best annual, zinnias. A bed or two of zinnias is really beautiful to look at plus brings lots of butterflies to visit.
