Feel free to post your pictures and information on your experiences with Butterfly Host Plants.
Host plants are those plants, vines, trees, & grasses that the female butterflies and moths use to lay their eggs. The host plant will provide nurishment, and shelter for the larval stage (caterpillar) of the butterfly, and often nectar for the adults too.
I guess I need to ID this guy....it is a Varigated Fritillary! It uses plants in violet family, it's host here is the ordinary pansy.