Seed stratification is a process of simulating the natural conditions seeds would experience when overwintering outdoors in order to break winter dormancy and begin stratification. This is required for most temperate carnivorous plants seeds being germinating indoors. It is not necessary for outdoor plantings or most tropical plants. Temperate carnivorous plant seeds require a cold moist period to trigger germination. This is especially true of Sarracenia, Drosera, Dionaea, Darlingtonia, and other zone 6 or less plants. Refrigeration alone is not enough. Contact with moist CP soil or peat moss is important. The target is a minimum of 45°F for 45 days, but temperatures of 0°F-45°F are fine. Longer time is fine also. You can refrigerate potted seeds, or seeds in a baggie mixed with damp peat. Keep an eye out during stratification so that the conditions remain cold, and especially do not go dry. Temperature fluctuations are recommended. I typically stratify for 120 days with temperatures fluctuating between 25°F and 45°F: freeze-thaw-freeze-thaw…just like Mother Nature.