I'd say those are the physalis. It's a perennial and an agressive spreader too. It could have been planted years ago. The nicandra is annual but one heck-of-a re-seeder. If allowed to set seed they come up all over.
Tomatillos (Physalis ixocarpa) probably, but because there are many members of the Physalis genus and some of them are poisonous to cattle and horses, I wouldn't eat yours unless you could get an in-person positive ID from a knowledgeable source.
I grow tomatillos every year, but haven't planted any since the first year I grew them. That leads me to believe that yours could have easily been planted by a bird.