Looks like a potato plant to me.

Definitely potato.

Really, we could start a thread on this, I bet other people would have interesting finds to add. Like I found some pintos that sprouted in my bin last week - I transplanted them to the veggie garden with the pole and bush beans to see what happens. Tomatoes were in there last fall and some definite mystery seedlings this weekend that I wished I could figure out whether they were something I wanted or not too!

Lisa B

Potato, cool! So what do I do now? Can I transplant it? I have no idea how to cultivate taters.

Thanks,
Stacy B.

Do you reckon it's a sweet or white 'tater, Stacy B? Kat grows her 'taters in straw, so I guess they aren't fussy, but I am by no means an expert at 'tater growing.

It is not sweet taters. If I were you,I would let it grow
in the compost pile. If you deside to transplant be very gentle and dig it out with as much dirt attach to the plant
to reduse shock. You know that granny smith apples were
discovered in Australia in a compost pile and a new apple came into existence. Now we all use it as exellent apples in our pies.
Felix

Potatoes are prone to many diseases and pests. If you aren't up for the work, I would just throw it out or put it somewhere where it is not in the way, just to see how it does in the wild.

Or,
You can try sweet potato. It is not a real 'potato', but it has eatable tubers just like potato plants, plus it is very disease and pest resistant. On top of all that, sweet potato plants are a type of Morning Glory, so you get the flowers and foliage as well! You can find sweet potatoes at nearly any grocery store, just make sure to buy the generic sweet potatoes to make sure they aren't patented or copyrighted.

It's definitely a white tater. I guess I'll leave it there and see what happens. We get lots of critters in our compost pile, though. We've seen possum and armadillo over there...will they eat my tater?

How do I know when it's ripe?

In the fall or when the foliage turns brown the potatoes will be as ready as they will ever get. Dig 'em out then.

I think a 'what's in your compost pile' thread would be fun. I have some ee's in mine that I didnt plant. They are totally diff. from the others I have. I peeked over the nieghbors fence to see if they came from there and didnt see any lol. Last year I had a birdhouse gourd growing from the compost pile- took me awhile to figure out what it was.