How do you decorate your floor.

What I mean when I say that is if I say want to make a grass floor would I make grassblades and duplicate it a lot, or just get a flat texture and put that on a plane? Also how would you make something like a floor/wall/pillar look weathered or beaten up look with like grass coming out or water in it or chunks taken out. Sorry if this is a really stupid question, I'm just learning textures properly and couldn't really find any good sources that answered. Thanks