Daylily is the common name of the species, hybrids
and cultivars of the
genus
Hemerocallis ( ). The flowers of these
plants are highly diverse in colour and form, often resulting from
hybridization by gardening enthusiasts. Thousands of registered
cultivars are appreciated and studied by international
Hemerocallis societies. Once considered part of the
Liliaceae family, such as
Lilium (true lilies), the genus name was given
to the family
Hemerocallidaceae in
later circumscriptions.
Description
These plants are
perennial. The name
Hemerocallis comes from the
Greek
words (hēmera) "day" and (kalos) "beautiful". The flowers of
most species open at sunrise and wither at sunset, possibly
replaced by another one on the same stem the next day. Some species
are night-blooming. Daylilies are not commonly used as cut flowers
for formal
flower arranging, yet they make
good cut flowers otherwise as new flowers continue to open on cut
stems over several days.
Originally
native from Europe to China
, Korea
, and
Japan
, their large showy flowers have made them popular
worldwide. There are over 60,000 registered
cultivars. Only a few cultivars are scented. Some
cultivars rebloom later in the season, particularly if their
developing seedpods are removed.
Daylilies occur as a clump including leaves, the crown, and the
roots. The long, often linear
lanceolate
leaves are grouped into
opposite flat fans with leaves arching out to
both sides. The crown of a daylily is the small white portion
between the leaves and the roots, an essential part of the fan.
Along the flower stem or
scape, small
leafy "proliferations" may form at
node or in
bracts. These
proliferations form roots when planted and are the exact
clone of the parent plant. Some daylilies show
elongated widenings along the roots, made by the plant mostly for
water storage and an indication of good health.
The flower consists of three
petals and three
sepals, collectively called
tepals, each with a
midrib in
the same or in a contrasting color. The centermost section of the
flower, called the throat, has usually a different and contrasting
color. There are six (sometimes seven)
stamens, each with a two-lobed
anther. After
pollination,
the flower forms a pod.
The common Daylily has potential to become a
noxious weed and is listed as such by the
Wisconsin
Department of Natural Resources . While sometimes planted due
to their ease of growth and the fact that they produce a flower,
non-clumping varieties of daylily can quickly overrun a garden.
Once established, it is difficult to remove runner daylilies from
the yard.
Cultivars
Daylilies can be grown in USDA plant
hardiness zones 1 through 11, making them
some of the most adaptable
landscape
plants. Most of the cultivars have been developed within the last
100 years. The large-flowered clear yellow 'Hyperion', introduced
in the 1920s, heralded a return to gardens of the once-dismissed
daylily, and is still widely available. Daylily
breeding has been a specialty in the United
States, where their heat- and drought-resistance made them garden
standbys during the later 20th century. New cultivars have sold for
thousands of dollars, but sturdy and prolific introductions soon
reach reasonable prices.
The Tawny Daylily (
Hemerocallis
fulva), and sweet-scented
H. lilioasphodelus
(
H. flava is an illegitimate name), colloquially called
Lemon Lily, were early imports from England to 17th century
American gardens and soon established themselves. Tawny Daylily is
so widely growing wild that it is often considered a native
wildflower. It is called Roadside or Railroad Daylily, and gained
the nickname Wash-house or Outhouse Lily because it was frequently
planted at such buildings.
Hemerocallis is one of the most hybridized of all garden plants,
with registrations of new hybrids being made in the thousands each
year in the search for new traits. Hybridizers have extended the
plant's color range from the yellow, orange, and pale pink of the
species, to vibrant reds, purples, lavenders, greenish tones,
near-black, near-white, and more. However, a blue daylily is a
milestone yet to be reached.
Other flower traits that hybridizers develop include height, scent,
ruffled edges, contrasting "eyes" in the center of the bloom, and
an illusion of glitter or "diamond dust." Sought-after improvements
in foliage include color, variegation, disease resistance, and the
ability to form large, neat clumps. Hybridizers also seek to make
less hardy plants hardier in the North by breeding evergreen or
semi-evergreen plants with those that become dormant. All daylilies
are herbaceous perennials - some are evergreen or semi-evergreen
while some go dormant in winter, losing their foliage. Although,
there are a number of northern hybridizers that specialize in the
advancements of the dormant daylily.
A recent trend in hybridizing is to focus on
tetraploid plants, with thicker petal substance
and sturdier stems. Until this trend took root, nearly all
daylilies were
diploid. "Tets," as they are
called by aficionados, have double the number of chromosomes as a
diploid plant. Hemerocallis fulva 'Europa', H. fulva 'Kwanso', H.
fulva 'Kwanso Variegata,' H. fulva 'Kwanso Kaempfer,' H. fulva var.
maculata, H. fulva var. angustifolia ,and H. fulva 'Flore Pleno'
are all triplods which cannot set seed and are reproduced solely by
underground runners (
stolons) and division.
Usually referred to as a "double," meaning producing flowers with
double the usual number of petals (
e.g., daylily 'Double
Grapette'), 'Kwanzo' actually produces triple the usual number of
petals.
Culinary use
The flowers of some species are edible and are used in
Chinese cuisine. They are sold (fresh or
dried) in
Asian markets as
gum jum or
golden needles
(
金针 in
Chinese; pinyin: jīnzhēn) or
yellow
flower vegetables (
黃花菜 in
Chinese; pinyin: huánghuācài). They are
used in
hot and sour soup, daylily
soup (金針花湯),
Buddha's delight, and
moo shu pork. The young green leaves
and the
tubers of some (but not all ) species
are also edible. The plant has also been used for medicinal
purposes. Care must be used as some species can be toxic.

Dried golden needles
Species
This is a list of
species, not of
cultivars, which number in the thousands:

Illustration, 1885

Hemerocallis thunbergii

A Hemerocallis fulva longituba
commonly called a "Red Magic" daylily for its color
combination
References
- Sunset Western Garden Book, 1995:606–607
- "Weeds of Wisconsin". US Department of
Agriculture. retrieved 10-26-09.
- Daylilies undated info page at University
of Nebraska. Accessed August 1, 2007.
See also
- Arlow Stout - pioneer in the
hybridization of daylilies
External links