Plants often produce seeds at the wrong time for new plants to survive. They produce seeds in the summer and fall that survive the winter and grow into the new plants the following spring.
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Stratification of seeds, either natural or artificial, helps some seeds break dormancy. Seeds are kept moist and at temperatures below 40 degrees Fahrenheit for a specific length of time. Some seeds require temperatures below freezing in order to break dormancy and germinate.
Seed banks store seeds in controlled environments with temperatures well below freezing. Seed banks preserve seeds in vaults in the event of global catastrophe and to preserve genetic diversity.
Annual plants die every winter and are unable to survive a cold winter. They produce seeds throughout the summer which survive temperatures far below freezing in order to germinate and grow into new plants the following summer.
Perennials survive more than a single season, sometimes for many years. Their seeds are more likely to require stratification than annual seeds and some won't germinate until two or more winters have passed.
Seeds that have been frozen will probably grow. It depends on the length of time they were frozen, how they were stored and what type of seed it is.