Why Plants Go Dormant in the Winter

dormant plant in winter

Like any sane homeowner this time of year, you might be looking at your patchy brown, dormant lawn, and thinking, “why in the world does my lawn look like this?”

Why is it for at least a quarter of the year, does the grass I worked so hard to keep healthy look like it’s been in the Sahara desert during a drought?

Maybe you’re familiar with dormancy as a concept, but you’re not quite sure what it means. 

In order to truly bring your garden to its fullest potential, it is beneficial to understand how your plants work. The plants in your garden are designed to survive harsh conditions like a Texas Flash freeze.

If your garden and lawn weren’t equipped with the ability to endure conditions less than ideal, you would be replacing all dead landscaping with cold snape or heatwave.

It is important to understand why plants go into dormancy and how they can recover to thrive once conditions become ripe.

What is dormancy? And why is it necessary for plant life?

Winter poses a massive problem to most living creatures. Humans bear down in cold temperatures by wrapping themselves in thick layers, placing themselves beside a cozy fire with a warm cup of coffee or hot cocoa. Some animals grow a thick winter coat to insulate their body temperatures.

Other animals, like bears, squirrels, bumblebees, go through a state of hibernation during the winter. Dormancy is like the plant form of hibernation.

Some plants from bulbs to certain perennials can “retreat” below ground and wait out the cold beneath the earth and snow where the temperature is often much warmer.

When it gets warm enough, as spring comes, they can leave dormancy to resume growing again. Sort of like a plant hibernation!

Benefits of Dormancy

Dormancy allows perennial plants to take a much-needed period of rest and conserve energy until more favorable conditions arrive. Think of dormancy like putting on the brakes.

It slows down plant life and growth to a near stop. Instead of exerting energy in an attempt to grow, they know to stop growing and conserve energy until ideal conditions return.

Just like a human body while it is sleeping, plants use the period of arrested growth to restore their bodies.

The plant strengthens its membranes, breaks down protein and remakes it again, and redirects attention to the roots for it to strengthen so when the plant resumes growth, the roots will be able to support themselves. 

Dormancy is for more than just cold weather. A plant can enter dormancy during a drought until it receives good rainfall.

Or when nutrients run low until it receives any type of fertilization. Or This can be rain after a drought, adding fertilizer after depletion, or the return of warmer weather. 

A plant can enter dormancy to protect its soft tissues from freezing temperatures, dry weather, or water and nutrient shortage.

Unlike humans or animals, plants don’t have the ability to find shelter in a home or cave; instead, they are exposed to the elements day in and day out.

It is also important to remember that plants contain a lot of water. They average about 90% of water within their stems, bodies, leaves, etc; far more than a human or animal.

When the water within plants is exposed to winter temperatures, the water within them begins to freeze, forming ice crystals.

Process of dormancy

Every living thing has a type of biological clock that signals times of rest. For humans, we feel fatigued as we reach our bodies’ physical limitations. Fatigue is our bodies sounding an alarm to declare it is time for rest.

Our bodies are tuned to respond to darkness with heavy eyelids and a need for rest. Just like us, plants are deeply affected by light exposure.

As the nightfall begins earlier every day, sunlight exposure decreases, and temperatures decline, it signals to the plant its time to enter dormancy.

As the length of sunlight shortens and a plant has recognized the need for dormancy, the process begins. Plants will first release chemicals to flow throughout the plant that will decelerate the photosynthesis process, decrease respiration, and bring growth to a halt.

The halt in growth allows the plant to conserve energy and resources to focus on surviving through the harsh conditions. Focus then shifts to maintaining the cell membranes and breaking down and remaking protein.

The signs of dormancy are not just internal changes. Dormancy results in fascinating external changes as well. One of the most commonly known signs of dormancy is the browning of leaves before they fall to the ground.

Leaves contain a large amount of water and primarily serve to aid in the photosynthesis process. As mentioned earlier, water freezing is a huge danger to plants during winter, and the process of photosynthesis slows to a halt during dormancy.

The loss of the leaf reduces the surface area of the plant’s exposure to the cold and lowers the risk of freezing. It also aids in retaining essential nutrients through the winter. 

Trees in particular have fascinating adaptations to deal with the colder weather which gives incredible insight into the process of dormancy.

Like with other plants, when the temperatures lower, it triggered the start of winter and the plant recognizes this change.

While most plants shed their leaves to prevent water loss or freezing, these trees use their energy to move the inner liquids around.

This allows the fluid to freeze safely in “extra-cellular” areas or spaces that are outside of the cells. 

Other trees work to add extra compounds like sugars or salts to their inner liquids in order to lower the freezing point, essentially creating their own form of antifreeze.

These trees are most commonly referred to as evergreen trees. Unfortunately, not many native Texas trees are evergreen.

Give a helping hand

As we have learned, our plants are amazing at self-preservation. They are equipped with the ability to survive the harshest conditions, but it does not hurt to lend a helping hand.

There are strategic things we can do as homeowners or gardeners to ensure our favorite plants survive to flourish in the next season. Applying a layer of hay or mulch helps hold in moisture and heat, or a plant-protecting blanket can shield against frost or unfavorable weather.

Trees and shrubs benefit from added dormant oil to ensure it does not suffer from an insect infestation as a borrowing bug tries to find warmth in its bark.

Or just an extra dose of nutrients in the fall to ensure it has all it needs to last through the winter with strong renewed roots.

Gecko Green offers dormant oil and fertilization in its Tree and Shrub program as well as an excellent Bed weed control program to keep your flower beds in tip-top shape. Call us today for a free quote!

Call for a free quote today!