Blue Porterweed, (Stachytarpheta jamaicensis (L.)Vahl according to the IBS Atlas of Florida Vascular Plants), is supposed to be a great nectar plant. I saw a Monarch have a sip from one once, but she didn't stick around long enough to get a picture. I saw a White Peacock Butterfly nectar on it briefly too. I'll add more as I see more...

I saw more! Here's a Gulf Fritillary Butterfly enjoying the Porterweed. I saw a Long-tailed Skipper Butterfly take several sips from it too, but it never stopped long enough for me to get a picture.

Three Spotted Skipper Butterfly Sips Porterweed Nectar:

A BIG Thank you to JoAnn O'Neill! She gave me two GIANT Porterweed Plants, so I'll be on the lookout for more pictures to take and put here. Porterweed is beginning to live up to its reputation as a great butterfly nectar plant.