I suppose one way to minimize risk is by purchasing a few shares in a major player like POT and a few shares in an emerging story. One may have more upside than the other, but it's about buying something currently out of favor and holding on for another phase of love potash love.

http://ezymoneystock.blogspot.com/ has a few articles on wpx, a junior potash company. It's positive coverage for potash overall. Although most importantly, I think sometimes the juniors help bring more interest to an area than the major blue chips.