Plant butterfly weed (Asclepias), parsley, dill, rue and pipevine to encourage butterflies in your garden. The foliage of these plants provides food for the caterpillars. Aristolochia fimbriata is a lovely ground-cover-type of pipevine that is covered each year by the pipevine swallowtail caterpillar at the UT Gardens, Jackson. It may be a little hard to find for sale but is worth seeking out.