Jouke Postma, author of SimRoot, offers advice on how to get started with a scientific model.

Simulations aren't all fun and games
The Art of Modeling
Models are useful. If you are interested in discussing just how useful they are, please visit the modeling skepticism page. On the pages below I will give info on models that may be of use for root researchers. I also tried to give some thoughts on programming models. I don't expect to be exhaustive on the subject at all, but rather will share some of my experiences.
Several students of Jonathan Lynch have worked on the developed SimRoot, a root architecture model. In combination with SimRoot we have developed DepZone and have linked SimRoot to the DSSAT models.