Where Do All the Plants Go in the Winter?
How do plants survive winter? Learn about their remarkable cold-weather adaptations in this community contribution, featuring digital artwork by the author, Jennifer Deeks.
COMMUNITY CONTRIBUTION
My gardens have been hidden under a deep blanket of snow. A few stems pokedout here and there, but otherwise you would never guess how lush those spaces are in July. When the snow melts, all that remains is a muddy mess.
As the soil warms, plants magically spring to life, seemingly out of nowhere. When temperatures are low and resources scarce, animals can grow more fur, seek shelter, or turn up the thermostat and cook a pot of soup. Rooted in place, plants don’t have that luxury, and their adaptations to manage cold weather are truly remarkable.
The plant version of hibernation is called “dormancy”. Triggered by colder weather and shorter days, plants gradually shut down their metabolisms and go to sleep.
In the winter, water is mostly frozen and not readily available, so moisture conservation is particularly important. With their large surface area, leaves are a primary source of water loss, so they are one of the first things a plant lets go of in a process called “abscission.”
Equally critical is that when water does freeze, the ice crystals expand and can damage cell walls. To address this, plants do things like move water into storage below ground into roots and tubers, create their own antifreeze compounds, and move water from inside cells to between them to allow for expansion without causing damage.
Evergreen plants like spruce trees or holly handle the moisture problem differently. These plants have leaves designed right from the get-go to reduce water loss. Their narrow needles have a smaller surface area from which to lose water. They also have a built-in layer of air that helps act as an insulator and a thick, waxy outer layer called a “cuticle” that holds water in. This way, they can keep their leaves all year round and continue growing, although more slowly, through the winter.
Below ground, soil temperatures do not fluctuate as much as air temperatures, so it is a safer place for plants to store water and carbohydrates as they prepare for the next growing season. If the soil temperature pops above freezing for a while, a little bit of root growth will occur – particularly for trees – but mostly the plant is just resting and saving energy – a good winter lesson for us all, I think.
In the coming weeks, plants will begin to respond to the warmer temperatures and more daylight as signals that it’s time to leave dormancy behind and get growing. I know I’m counting the days until I see my plant friends again!
Thank you to sponsors of The Owen Sound Current Writers’ Fund, who make these community contributions possible. Contributions from the community do not necessarily reflect the opinions or beliefs of The Owen Sound Current and its editor or publisher.
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