The Famous Rejected Article: Identifying Dormant Daylilies in the North

Identifying Dormant Daylilies in the North

by Di DeCaire                                                            copyright April 15,2014


Northerners become positively radiant when they talk about dormant daylilies. If you live in the south you might wonder why. What’s all the excitement about?

Dormants are commonly green and pristine with no ratty or browned foliage upon emergence. Besides being visually pleasing, their clean appearance engenders a sense of confidence in the way dormancy works. Dormant foliage is  an attractive deep green through this first phase of growth. Some dormant daylilies are bluish green, and these are the most prized of all.  

Dormant daylilies make us truly delight in - and love everything about daylilies, from the very beginning to the very end.
The phases that a dormant daylily goes through are emergence, foliage growth, scaping, blooming, pod set and dormancy. There is a shutdown in active growth when a daylily goes dormant, ensuring that the fibrous roots are able to economize their sugar supply until spring. No new growth will develop during the winter. This good timing helps them bloom to their fullest potential in northern climates.

Emerging dormant daylily
Rising temperatures activate a growth hormone called gibberellin in early spring. Rapid cell division occurs in the meristem and is triggered by gibberellin. It’s helpful to understand what a meristem is and its role in relation to dormancy. The meristem of a daylily is a lateral section of cell tissue located just above the crown. It is responsible for the origination of all cell tissue, both above and below ground. A damaged meristem means a damaged plant. A dead meristem means a dead plant.

In autumn when all the foliage dies back to the ground, new buds for the next year’s growth called resting buds develop from the terminal meristem. They remain underground and cannot be seen. These resting buds are exceptionally tough and hardy. A chemical similar to anti-freeze helps defend them from frost damage so when the new fans start growing in spring they normally have better resistance to late frost damage than tender evergreens.  

Snow is a superior insulator for daylilies in the north. The earth’s heat radiates upward and bounces back down from the snow cover rather than escaping into the atmosphere. Evergreen cultivars may fare better with this additional snow cover as well.

Proper planting of a daylily is crucial because if the crown is situated too low under the surface of the soil the meristem may suffocate, but if planted too high it may be exposed to frost damage over the winter months and into early spring as well, when late frosts occur. I try to plant the top of the crown about three quarter inch deep.

To correctly identify an emerging dormant daylily look for clean fans with no browned or straw colored tips on the new growth. In the case of a late frost after growth has begun, some dormants may have a minor amount of browning on the leaf tips. The past year's foliage will have completely died off the previous fall and by springtime is lying on the ground in a very wizened state. It’s fun and easy to count the number of growing points at this stage.

Some dormants are referred to as hard dormants because they shut down early and completely. Shortening day length in the fall may trigger hard dormancy but this theory is unproven. Other dormants appear to need a succession of freezing temperatures for growth to cease.

The concern about evergreen daylilies in northern climates has to do with their perpetual growth. They are not programmed by nature to stop growing during the winter months like dormants. When evergreens manage to resume growth during winter thaws, the existing foliage as well as any new growth freezes when temperatures drop again. This winter growth is a waste of the plant’s energy reserves, affecting its overall vitality. Flowering potential is often diminished.
Rescue fans arising from a frost damaged evergreen crown make this daylily appear to be a late emerging dormant daylily - until the decaying growing point is uncovered. These rescue fans experienced frost damage as well, during subsequent frost. The true dormant daylilies carried on valiantly and were growing strong in the same garden on the same day
In my region, evergreens are identified in the spring by their browned foliage and possibly mushy or curled over fans. They often appear disheveled. The fall and winter growth freezing and the next round of growth getting trapped in the dried up brown parts cause this. When the browned debris is pulled off green leaves may spring forth, unfolding like an accordion. If another frost occurs this new growth is subject to damage once again, whereas dormants show some level of resistance to spring frost damage.

When evergreen fans freeze and brown all the way down to the ground it is cause for concern. One has to hope that the meristem has not been damaged. It can be surprising to revisit a dead looking clump and see full size, healthy fans arising a couple weeks later but it often happens. Conversely, there may be a few empty spots in the garden where evergreens with the same appearance were not so lucky. Evergreens typically have lighter, brighter green foliage than dormants. 
Mushy evergreen decay

It’s almost worse for us northerners when only a portion of the plant dies off because it is generally just a matter of time before more trouble occurs, leaving us in a state of uncertainty. Rescue fans may emerge from the meristem in an awkward assemblage as a way of helping the plant survive. These fans are often too small and narrow to give rise to a productive scape.

Evergreen clumps should be checked for symmetry. An empty spot is a sign that some portion of the plant may be dead. There are evergreens that are quite hardy though, often having been bred in the north. These have some brown foliage in the spring but display good symmetry. It’s possible that some dormant genes are mixed in and they are not 100 % evergreen.

Crossing dormant and evergreen daylilies has proven successful for me in some cases. These seedlings possess the best qualities of both worlds, the coveted southern flower traits blended with the desirable hardy habit. These crosses often result in what are determined to be semi-evergreens.

To identify semi evergreens in the north look for clumps with foliage that have some degree of brown at the tips, not as far down as evergreens, and no mushy spots. There are a number of variations resulting from the perpetual blending of dormants and evergreens by hybridizers worldwide.

Daylilies that are nearly dormant are sometimes classified as semi-evergreen because they are not completely green at the tips. The longer outer leaves surrounding the clean emerging growth in the center have some degree of browning. These types often possess the same deep green or blue tinged foliage as dormants and are normally quite hardy.

Dormant daylily behind an evergreen upon emergence
Some semi-evergreens are closer to evergreen. The leaves are of fairly equal height, the tips somewhat browned, and may be a lighter shade of green than the near-dormant semi evergreens.  These variations can have quite minor differences and this makes identification tricky. Seedlings that are very close to dormant with a negligible amount of brown on the outer leaves can be hard to classify. Semi evergreens that look almost like hardy evergreens are also tough to classify.

For the more difficult to assess semi-evergreens in my hybridizing beds I try to make note of them as being near dormant, near evergreen habit or falling in the middle. The seedlings are labeled when they emerge in April (it’s a small program so I can afford to fuss). This assessment is not totally accurate at this early stage but helps when hybridizing. I paint white labels purple or green. Purple is for dormant, green is for evergreen and the semi evergreens are left unlabeled.


To compare the worrisome experience of brooding over the more tender evergreens to feeling a Zen-like connection to dormant daylilies while watching them emerge, results in one outcome for northerners. The dormant daylilies win our affection and we often want to collect and hybridize for more.

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