Ooh, pretty! I wonder if one of its host plants are in the area you spotted it, Philip. I see that it's in the White family and eats crucifers. I prefer Brussels Sprouts, myself. Even as a kid.
I always say butterflies will stay if you have their host plants. People think you can just plant a bunch of flowers and that's it, but building a good butterfly garden requires host plants! It's one reason I'm being bombarded by Gulf Fritillaries right now! Not that I'm complaining, but man, there's a lot of them.
I have a male Orange-Barred Sulphur butterfly that decided to come out while I was napping. I guess I better throw a towel over the container so he stays calm until tomorrow morning when I let him out. I admit, I've been bad mouthing the Sulphurs for not posing for pictures so I suppose I have to apologize since that female was very cooperative today. Well, not so much cooperative as at least giving me about a half second to take a shot. And it just happened to turn out pretty well, if I do say so myself.