As a daylily, my experience of winter is not one of death, but of profound rest, a state you call dormancy. This shift is triggered by the shortening daylight hours and falling temperatures of autumn. From my perspective, these environmental cues are a critical signal. My above-ground growth, the lush green leaves that have been busy photosynthesizing all summer, must now be retired. Continuing active growth would be disastrous; the water in my cells would freeze, expand, and rupture my delicate tissues, causing fatal damage. Therefore, I initiate a carefully orchestrated shutdown process. I begin to translocate valuable nutrients—sugars, starches, and proteins—down from my leaves into my underground storage organs, the crown and roots. This is my survival pantry, the energy reserve that will sustain me through the cold months and fuel my rebirth in spring.
What you observe above ground is the most visible sign of my dormancy. My leaves, having surrendered their nutrients, will turn yellow, then brown, and eventually collapse. They may become mushy or simply lie limp on the soil. It is crucial for you to understand that this is a natural and necessary process. Do not be alarmed by this apparent demise. This dead foliage actually serves a purpose, providing a thin layer of insulating mulch to protect my crown from extreme temperature fluctuations. While you may be tempted to tidy up by cutting all the foliage back to the ground immediately, it is beneficial to leave it until the dormancy is fully established, usually after a few hard frosts. This allows the final energy transfer to complete and gives me a bit of extra protection as the coldest weather sets in.
While the scene above ground appears lifeless, the true action is happening below the soil surface. My crown—the compressed stem tissue at the base of the plant where the roots and leaves meet—is the command center of my dormancy. Packed with stored energy, it is very much alive. Within this crown are the dormant buds, often called "eyes," which contain the entire blueprint for next year's growth. These buds are in a state of suspended animation, protected from the cold by the surrounding soil and any mulch you may provide. My root system also remains alive, though largely inactive, holding me firmly in place and ready to absorb moisture from the soil during occasional winter thaws to prevent my crown from desiccating.
This period of dormancy is not optional; it is an essential part of my annual cycle. The sustained cold period, known as vernalization, is required to break the dormancy of the buds in my crown. Without experiencing a sufficient number of days with temperatures below a certain threshold (typically around 40°F or 4°C), my internal hormonal balance cannot reset. When spring arrives, the combination of warming soil and lengthening days will signal that it is safe to grow again. But if I have not had my required chill period, my growth may be weak, stunted, or irregular. This is why daylilies like me, which are hardy perennials, struggle in climates with very mild winters; we need the cold to trigger our robust spring performance.
