What Happens to Plant Life During the Winter?

1/31/2022 8:53 pm

It seems as though your backyard is very inactive in the winter. But that’s not true – so much is

going on underneath the surface.

Annual plants die in the fall after they scatter their seeds directly on the ground or include them in

fruit that is consumed by animals and deposited elsewhere. When a seed has been exposed to low

temperatures for long enough, a process known as cold stratification, plant hormones trigger the

end of dormancy. At this time, if environmental conditions are favorable — say there's enough

water around — the seed can then germinate (begin to grow and put out shoots). This is also a

process governed by plant hormones. Some examples of annual plants are calendula, zinnia,

forget-me-nots, and nasturtium.

Perennial plants (those that come back every year) are active underneath the surface of the soil. Just

like we struggle with cold weather, plants are the same. If plants were actively growing during the

winter, the water in the trunk, stems and leaves would freeze, causing tremendous damage to these

structures, therefore these plants go dormant in the winter.

So what happens when plants go dormant? During the active months of growth (April-August),

each plant is using the photosynthetic process to change carbon dioxide, water, and certain

inorganic salts into carbohydrates. These are used by the plant or stored for use during the

winter. At the end of the growing season, plants begin to move these sugars and carbohydrates

from the leaves down in the roots to nourish the plant for the winter months. At this point, the

plants are no longer growing. Dormancy is the way plants conserve energy by using the stored

sugars and carbohydrates they produced during the growing season to survive the winter.