Daylilies, scientifically known as Hemerocallis, are popular perennial plants that offer vibrant summer color. A common misperception is that daylilies grow from bulbs; they actually grow from fleshy, elongated roots attached to a central crown or fan. These thick roots act as underground storage organs, holding the water and nutrients the plant needs to survive periods of stress. Proper winter storage is necessary when planting is delayed or when overwintering non-hardy cultivars in climates with severe freezes, ensuring the plant remains viable until spring.
Preparing the Roots for Dormancy
Preparation for storage begins immediately after the roots are dug up from the garden or received bare-root. Trim the foliage back to about six to twelve inches to reduce moisture loss and make the plants easier to handle. Gently remove any large clumps of soil clinging to the roots by shaking or carefully brushing them off. Washing the roots is not recommended, as excessive moisture can invite fungal diseases during storage.
Once the roots are cleaned, they require a short period of air-drying to cure the outer layer. Place the roots in a cool, shaded, and well-ventilated area for approximately 24 to 48 hours. This curing process allows minor cuts and abrasions to heal and helps prevent the growth of mold or rot. Before packing, carefully inspect each root and discard any that show signs of damage, shriveling, or soft spots.
Selecting Storage Materials and Containers
Choosing the right storage medium and container is important for maintaining the roots’ viability. The function of the storage medium is to create a microclimate that prevents the fleshy roots from drying out (desiccation) while also allowing for air circulation. Peat moss, shredded newspaper, or wood shavings are excellent choices because they absorb and retain a small amount of moisture.
The medium must be only slightly damp, not wet, to prevent fungal or bacterial growth; it should feel like a lightly squeezed sponge. Layer a few inches of the damp material in the bottom of a container, such as a cardboard box or a paper bag. Arrange the daylily roots on top, ensuring they are completely covered by the packing material. The roots should not touch each other if possible.
Cardboard boxes and paper bags are preferred containers because they naturally wick away excess moisture and provide essential ventilation for the dormant roots. If a plastic bin must be used, punch several large holes in the sides and lid to allow air exchange. Proper ventilation is vital to disperse any gases produced by the roots and prevent humidity buildup, which could lead to crown rot.
Ideal Temperature and Monitoring Conditions
Successful winter dormancy requires a cool, consistent temperature that suppresses active growth while preventing freezing damage. The ideal storage range is between 35°F and 45°F, just above the freezing point. Locations like an unheated basement, a protected garage, or a root cellar are suitable, provided they maintain this stable, cool temperature. Fluctuations in temperature can cause the roots to break dormancy too early or freeze, compromising the plant’s health.
During the storage period, a monthly check of the roots is necessary to ensure conditions remain optimal. Inspect the roots for two primary problems: shriveling and mold. If the roots appear shriveled, the packing medium is too dry, and a light misting with water is needed to restore humidity. If any roots show signs of mold or a soft, mushy texture, they should be removed immediately to prevent the spread of decay.
Transitioning Roots Back to the Garden
The final stage of the storage process is preparing the roots for reintroduction into the garden in spring. The appropriate time for planting is typically after the last hard frost has passed and the soil is workable. Even with the best storage practices, some moisture loss is inevitable over a period of months.
If the roots appear slightly dry or shriveled when removed from storage, they will benefit from a simple rehydration process. Soak the entire root mass in a bucket of cold to lukewarm water for two to four hours before planting. This soaking allows the fleshy roots to absorb sufficient moisture, preparing them to take up nutrients and anchor themselves quickly in the soil.