Book 29, Question 28
Why do some seeds need a cold winter before they sprout?
Some wildflower and tree seeds are protected from sprouting too early.
If they sprouted in autumn, young plants might freeze. Instead, the seeds need a period of cold, damp conditions, which signals that winter has passed. Gardeners imitate this by putting the seeds in a damp paper towel in the fridge for weeks. This is called cold stratification.