PhysOrg.com explores an interesting question: Can We Grow Crops on Other Planets?
The answer is obviously “yes”, it’s just a matter of how. The article primarily discusses soil composition (along with the philosophical question of what, exactly, “soil” is), leaving out hydroponics and aeroponics.
In Labyrinth, we have taken the position that farming on Mars requires some not-insignificant preparation of the raw soil, using modified bacteria to remove undesirable trace elements and other bacteria (along with sewage and such from the settlement) to add biological content to the otherwise sterile dirt. This is partly for plot reasons, but partly based on familiarity with Keweenaw stamp sands.