What Is Vernalization?

The process of exposing seeds or bulbs to a prolonged period of cold temperatures. The goal is to satisfy the plant’s natural requirement for chilling in order to break dormancy and successfully sprout, flower, and/or bear fruit. Humans artificially perform vernalization by storing seeds or bulbs in refrigeration or freezers to imitate seasonal chilling hours. The exact time and temperature required varies between plants, yet is typically several weeks between 40 and 32°F. Many nut and fruit trees along with some varieties of garlic, milkweed, and flower bulbs require vernalization. Also known as ‘chill hours’.