Why frost kills plants.

  Have you ever wondered why some plants die when the frost hits, while others do not? Many people ask this question. There is a pretty cool answer for it. So why and what happens to a plant when thee is frost outside?

Some plants do very well in the cold weather months, while others die. The plants that die are traditionally from a warmer climate. These plants did not need to evolve into having the tools needed to survive winter or colder months. The surprising thing about all of this is, it is not the actual frost that kills a plant but the temperature of the plant. When the temperature inside the plant tissue reaches freezing.
Water expands when it freezes. When the water inside of the plant tissue freezes it expands and bursts open the cell walls of the plant. The plant when frost is still out appears to still be rigid and fine. When the frost goes away you will notice a different story. The plant will turn limp and lose its color. When the frost goes away, so does the ice formed inside the plant. Leaving broken cell walls and a dead or dying plant.
Some plants can endure the cold and winter months because they have evolved an almost anti-freeze like genes. Some plants survive the cold by shedding softer plant tissue and store their food in harder tissue. These would be trees. Other plants such as your root vegetables will store all of their food and nutrients in the root, the soil that holds the root also will act as an insulator. For a while the soil will keep the root from freezing. Some plants simple slow down their growth and they are just fine through the winter.
Here is a fun fact. Some plants like Garlic and onions can survive temperatures down to -30F!
I hope you enjoyed learning about frost and plants during the colder months.
Garrett.