AUGUST
2000: Features (print version)
DAYLILIES
OF THE FIELD
For
half a century, Robert Griesbach, PhD'55, has cultivated his garden,
working to build a better daylily. Griesbach's latest is a deep purple
beauty - named for his U of C mentor.
On
his five-acre farm, nestled between crops of corn and soybeans in Delavan,
Wisconsin, Robert Griesbach, PhD'55, spends his summers tending to more
than 10,000 daylily plants that form a tightly packed field awash in
hues ranging from pink and red to yellow and near white. Yet every year
or so, he disrupts this tranquil scene by digging up and transplanting
a few choice blooms, before applying herbicide to kill off the remaining
thousands. The next year, he starts the process over by replanting the
field with seeds produced from hand pollination.
The ritual is part of Griesbach's six-decade pursuit of
new daylily varieties. To date, he has introduced some 60 new daylily
plants through a number of nurseries, including Klehm's Song Sparrow
Perennial Farm in Avalon, Wisconsin, and Wayside Gardens in South Carolina.
A professor of biological sciences at DePaul University for 34 years,
Griesbach developed a new method for doubling the chromosomes in daylilies-with
four sets of chromosomes, tetraploids offer more color possibilities.
His latest creation is a deep, velvety purple daylily to be named in
memory of his mentor at the University of Chicago, botanist Paul Voth,
SM'30, PhD'33.
Griesbach's father, a church organist and choir director,
grew irises and other flowers on their city lot in Menasha, Wisconsin.
Though always interested in plants from working with his father, Griesbach's
interest in daylilies blossomed upon coming to the University and doing
graduate work under Voth. A 1940 Quantrell winner who himself had studied
under U of C botanist and daylily breeder Ezra Kraus, PhD'17, Voth suggested
that Griesbach study daylily dormancy and germination to arrive at a
more exact reading of the effect of cold temperatures on deciduous daylilies.
Voth was a dedicated mentor, hand-pollinating daylilies
to produce the seeds Griesbach used in his experiments. Unlike evergreen
daylilies, which keep their foliage year round and grow well in the
southern United States, deciduous daylilies lose their foliage in the
fall and are more common in the northern United States. Griesbach found
that deciduous daylily seeds must be in the ground at a near-freezing
temperature for six to eight weeks before they start to develop; they
can still germinate after being exposed to slightly warmer conditions,
but must remain at those conditions for a longer period of time. His
findings helped give evidence to what had previously only been noted
anecdotically.
After completing his graduate work in botany at Chicago,
Griesbach returned to teach at DePaul-where he had earned his bachelor's
and master's degrees-in its biological-sciences department, eventually
chairing the department for 14 years. At DePaul, he was able to blend
his scientific work in cytology and the genetics of polyploidy (plants
with more than the normal number of chromosomes) with what quickly became
a lifetime interest in breeding daylilies. "My research and my hobby
were all combined," he says. "I continued school, so to speak, on Saturdays
and Sundays."
What prompted his interest in breeding daylilies, he explains,
was the realization that "daylilies were going to become the most important
garden perennial." It's a strong statement from a generally mild-mannered
professor, but he saw plenty of evidence to back his argument: Daylilies
can flourish in a variety of soils, temperatures, and light intensities.
They also have a long growing season, from late spring to autumn; every
day brings a new group of blossoms; and, in the northern United States,
they can be grown without being mulched. But perhaps their greatest
feature is being extremely resistant to fungal and viral diseases. Today,
Griesbach's confidence has proven well-placed: The American Hemerocallis
Society boasts over 10,000 members, publishes the quarterly Daylily
Journal, and hosts regional and national conventions and growers' competitions.
Griesbach began his breeding experiments by working to
develop tetraploid daylilies, which have four sets of chromosomes instead
of the two sets common in many plants. In increasing the number of chromosomes,
his goal was to deepen the daylily gene pool and thus expand the possible
variations of color and other physical attributes. Taking the seedlings
left over from his dissertation experiments, he treated them with the
chemical colchicine, which caused their cells to begin to divide-creating
a duplicate copy of the chromosomes-without completing the cell-division
process. This plant was left with cells with the genetic material for
two individual cells.
Two years after his tetraploid first bloomed in 1959,
Griesbach formally introduced the new flower. Crestwood Evening, which
he had collaborated on with breeder Orville Fay, made its debut at the
1961 National Daylily Convention in Chicago.
The new tetraploids were noticeably different from their
diploid ancestors. With twice as many chromosomes, cell nuclei were
larger. With larger cells, the tetraploids had larger flowers, leaves,
and roots. An increased root system meant that the tetraploids could
absorb more water and nutrients, and thus grew more vigorously. Doubling
the chromosome number also meant that the tetraploids' color could be
more intense, because the new plants could have as many as four doses
of a given pigment, while diploids could only range from zero to two
doses.
Not all of the results were desirable. The new plants
were stiff and sometimes brittle. And, because they were temperature
sensitive, the first generation of tetraploids was not very fertile:
if the temperature exceeded 80° F, pollination would most likely not
take. But Griesbach eventually found that such undesirable qualities
could be bred out of the daylilies in second, third, and fourth generations.
Asked to name some of his favorite creations, Griesbach
thinks over his answer carefully. Ruby Throat, Towee, Baltimore Oriole,
Painted Trillium, and Blazing Sun win the honors. "One of my interests
was to work on certain colors that, at the tetraploid level, were not
very well established, and red was one of them," he explains. Ruby Throat
and Towee, for example, offered a clearer, less muddy red than previously
available. Although he has worked on many colors to improve their clarity
(how pure a color is), saturation, and intensity, Griesbach admits that
all his favorites fall in the reds and purples.
Retiring in 1989, Griesbach moved to Wisconsin with his
wife, Mary Lou, in 1991. The relocation took two years because he had
to transfer two crops of flowers-daylilies and lilies. In the end, Griesbach
transplanted several thousand plants from his home in Park Ridge, Illinois,
to his new farm in Delavan, Wisconsin. His summer 2000 crop now includes
3,000 daylilies blooming for the first time this year and representing
150 different parents. Of these 3,000, only three to four will be improved
enough for possible naming and introduction; those improved but not
significantly improved enough for introduction will be used for crosses
to produce seeds. The hope is that with each generation, the resulting
plants will become more and more improved in terms of the particular
trait for which Griesbach is breeding them.
Among the flowers growing in his field are several plants
of the Dr. Paul Voth daylily, to be registered with the American Hemerocallis
Society this summer. Griesbach plans to introduce the flower to the
public in 2001, which will be sold through Klehm's. Griesbach chose
to name this deep, velvety purple daylily after Voth both because, as
daylily hues go, it's one of the more "manly" hues, and because it's
in Griesbach's own favorite color range. "Dr. Voth was the one who really
got me interested and involved with daylilies in the first place," says
Griesbach. "I learned so much from him about daylilies, I just feel
that it's very appropriate to honor him in this way."