Russia regains control of lizard sex satellite

NASA has been doing gardening research aboard the ISS for years:

http://www.nasa.gov/mission_pages/station/research/experimen... http://www.nasa.gov/mission_pages/station/research/10-074.ht... http://www.gizmag.com/veggie/31613/

An orbiting satellite with plants would be expensive because it would need climate control and a way to both protect against too much sun and radiation and at the same time allow some sun for growing the plants. You'd also have to find very specific bacteria, fungus, plants, and other organisms that could survive that kind of environment, if you miscalculated then the experiment would quickly fail and it would be a huge waste of money (because you can't bring the capsule back to earth to study what did/didn't survive and it would be hard to visibly see what failed with just a camera and misc sensors).

You can probably work with a NASA project to get something aboard the ISS (if you're very lucky) but you'd have to show how it could benefit them rather than it just being cool to do.