Well, I have played this game with no rhyme or reason just random breeding and no record keeping. I even trashed my seeds with no regard for the future since I wasn't working by any recipe. This tactic seemed to work for me since I fluked on all 6 magic plants... 3 of them were "born" in the same breeding batch even!

Now that I have all the magic plants, I have decided to take a more serious approach to breeding since I have only discovered 132 breeds. I am only keeping one seed of each plant and higher tiered seeds get priority over lower tiered ones. I also have kept seeds from each of my magical plants and 15 of the most valuable one.