My condolences to your family. Your weather and climate are similar to mine, as are the varieties of butterflies that are found in your area. There are two types of plants for butterfly gardens: Nectar plants and host plants. Host plants are the ones butterflies lay eggs on that feed the larvae when they hatch. Nectar plants are the ones that the butterflies themselves feed from.
The location of your butterfly garden is just as important as the plants it will contain. Butterfly gardens need to be completely organic so if your neighbors use chemicals you won't want it close to anyone else's property line and you'll want to try an put in wind breaks that can help protect against chemical drift.
The plants should be chosen with the specific butterflies in mind that you want to attract. Swallowtail larvae will feed on anything in the carrot family from parsley to the green on regrown carrot tops. Monarchs will only feed on milkweed and they are voracious eaters so if you want to raise butterflies you will need extra plants that are isolated so that no eggs are laid on them.
Zinnias, passion flower, marigold, blue porterweed, clerodendrum... there are so many plants for attracting and feeding butterflies.
