What is Dormancy Anyway?

Winter is the season when many plants in your garden are dormant, but what does dormancy really mean?

Technically, the term “dormancy,” as it relates to gardening, refers to a state of temporary metabolic inactivity. In layman’s terms, the plant needs to rest from the growing season and dormancy is mother nature’s way of providing that rest period. It’s an interesting process and here’s how it happens.

During the summer months in which plants are actively growing, they busily use the photosynthetic process to change carbon dioxide, water and inorganic salts into carbohydrates which are stored in the roots of the plant. The plant then draws on them during the winter months when these elements are not readily available to keep it alive. During dormancy, plants stop their active growing period and conserve their energy so that they can survive by using these stored sugar carbohydrates until more favorable growing conditions appear in the form of warmer temperatures, water, and longer day length.

Plants go dormant in response to the change in day length and cooler temperatures. This can happen naturally as the days shorten and the temperatures drop during our fall and winter months. It can also happen artificially as is the case with bulb flowers like tulips, daffodils, and Easter lilies that are chilled, then brought out and “forced” to bloom in time for holidays such as Valentine’s Day and Easter.

If trees, shrubs, and perennials  remained actively growing throughout the winter season, the water that they take up would freeze in their trunks, stems, or limbs causing them to crack or split causing tremendous damage or death, so dormancy is the way a plant protects itself. The biggest problems come when we have an early warm spell in our area. If we have an unseasonably warm period of time and a plant breaks this dormant cycle too soon, it begins to send up new growth which will then be killed once the weather returns to its normal cold. Think about how many times our fruit trees have broken dormancy in the wake of warm March temperatures in our area, only to freeze once cold and snow return in April, thereby losing the entire crop.

This is not only the case with fruit trees, but also for your perennials and other shrubs in your garden. You can help protect those plants from this thaw/freeze cycle by putting a fresh layer of mulch down over these plants while it’s still cold. Since we never know what March will bring, now is a good time to make this application. The mulch should be 2-3″ deep for best results.  By keeping the roots at a more constant temperature, you can delay their response to a warming trend. Remove the mulch a little at a time once the weather truly begins to break in order to have the plants response be more in tune with the natural cycles of nature.                     

Dormancy is something to be thankful for and is a vital process for plants to survive our sometimes harsh and cold winters. However, if you are envious of nature’s ability to hunker down and sleep through the winter months in order to avoid the cold and snow and wish you could too, take heart- planting season is coming soon!