Strawberries, like many perennial plants, enter a state of reduced metabolic activity called dormancy. This resting period is a necessary survival mechanism that allows the plant to conserve energy and protect itself from harsh environmental conditions, such as freezing temperatures and lack of moisture. The cycle of growth and dormancy is essential for the plant’s long-term health and its ability to produce fruit in the following season.
Understanding Strawberry Dormancy
The onset of dormancy is primarily triggered by decreasing air temperature and shortening daylight hours, known as photoperiod. In the late summer and fall, the plant senses the reduced day length, which initiates cold acclimation, causing it to slow growth and develop tolerance to cold temperatures. This signals the plant to prepare for winter.
As temperatures drop further, the plant’s metabolism slows significantly, and it enters a deep dormant state. During this time, the leaves may turn reddish or die back, and the central crown, which holds the embryo flower buds, hardens to survive the cold. The plant must accumulate a specific number of “chilling hours”—time spent in temperatures typically between 32°F and 45°F—to ensure robust growth and fruit production once spring arrives. If a plant does not receive enough chilling, the flower buds may not open properly, resulting in a significantly reduced yield.
How Different Types of Strawberries Handle Dormancy
The depth and duration of this resting period vary depending on the type of strawberry being grown. June-bearing varieties exhibit the most pronounced and necessary dormancy, as they rely heavily on accumulating sufficient chilling hours during the winter. These types set all their flower buds in the fall, which then lie dormant until the spring, resulting in one large crop concentrated in a short window.
In contrast, everbearing and day-neutral varieties have a less intense dormancy period, especially in milder climates. Day-neutral varieties are less sensitive to day length and temperature, allowing them to flower and fruit continuously throughout the growing season. While these types may slow down or stop production during the coldest part of the winter, their chilling requirement is much lower.
Caring for Strawberry Plants During Dormancy
Preparing strawberry plants for winter is essential to protect the crown and ensure a productive harvest the following year. Before the ground freezes completely, clean up the patch by removing any old leaves, weeds, or debris. For June-bearing types, the foliage is often cut back to about one to two inches above the crown, a process known as renovation, to direct energy toward root health.
The most effective protection during dormancy is a thick layer of insulating mulch, with clean straw being the preferred material. This straw should be applied after the plants have fully acclimated to the cold. A layer of mulch, about four to eight inches deep, insulates the crowns from extreme cold and prevents the soil from undergoing repeated freeze-thaw cycles that can push the crowns out of the ground, a damaging process called “heaving.”
Although the plants are dormant, they still require some moisture to survive the winter. If the ground is not covered by snow and a prolonged dry spell occurs, a light watering is necessary to prevent the crowns and roots from drying out. The mulch should remain in place throughout the coldest months and can be gradually removed in the spring once new growth begins to emerge, ensuring the plants do not break dormancy too early and risk damage from a late frost.