Nah, that's normal! Like all plants, potatoes produce flowers so that they can have plant "Sex" to swap genes with other potato plants around them. Without this ability, they'd be unable to evolve. Those are just the fruits of the potato. It does happen, just not often enough for people to notice. You must have healthy plants Mike!
However, most every potato is started from the tubers rather than seeds. BUT... how else would potato breeders be able to develop new varieties without the seeds? It'd be impossible.
I read a few articles this spring where supposedly people grow potatoes from seed. Few claimed a major success but all plants that I know of produce something to keep their species alive.
FIVESTAR FAIL! Sorry Mike, totally missed the link under the pic! Yeah, I wondered about this too for a while, cause I'd never seen a potato fruit, but I know it had to happen. Did some googling and was surprised to see that they really did look just like tomatoes!
Cool pics once again, and thanks for sharing! Keep that garden porn coming man. It's making me really jealous!
We used to see this every year when my grandparents grew Almond potatoes. Never would have thought about it if my grandfather hadn't stressed that we could absolutelly not taste them. The fact that they where poisonous made them interesting to us kids.
If it was now I would save at least one plant, let the fruits ripen and save some seeds. That would be interesting for a geek like me!