Plant on large Asteroid? I'm just curious if it is possible for a plant to survive on a large asteroid. Some say no, some say it depends. 

With the scenario of an asteroid at about 1 AU from the Sun, receiving a similar amount of sunlight to Earth, and with wet soil or something similar.
It might depend on what qualifies as a plant.   A thin film of rugged mold for example . . . just maybe.

The tricky part is that asteroids are too small to retain an atmosphere and you need an atmosphere to have liquid water which plants and all life (so far as we know) needs.   I don't want to dismiss the possibility that there's underground water and some kind of very sturdy life that can eek out a living on the airless surface of an asteroid, but I wouldn't bet money on it.  I think it's unlikely, maybe unlikely multiplied by about 5 orders of magnitude.    It's very close to impossible.

That said, Ceres is an asteroid and Ceres may have a liquid underwater ocean.   Life in an underwater ocean is thought to be possible.