Breeding for tall daylilies has been a passion since the inception of my program.  I am six feet tall on a good day, and like daylilies that look me in the face.  A garden full of 24 inch tall plants is boring indeed!  Since I came to daylilies by way of perennial gardens featuring mixed borders I saw the need to develop daylilies to use as scrim plants, and at the back and middle of the border.  These plants are steps along the way to those goals.  I love to see six foot daylilies blooming in front of tropical looking foliage like Macleaya cordata and Miscanthus floridulus, also Arundo donax.  The garden shot at right includes A.B. Stout's H altissima based cultivar "Autumn Minaret".

A.B. Stout developed a well known series of tall daylilies using H altissima.  He predicted a “giant class” of daylilies over 5 feet tall (60”) to be possible in the future. (Stout pg. 82)  This article explores my breeding program and it’s progress in developing plants in this giant class.

Though many have used H. altissima and it’s progeny to breed for height I have had much more success and experience using H citrina.  In my experience H altissima-based plants have more willowy scapes and my H. citrina based seedlings are giving heights to 70” or more with much thicker scapes.  It seems to me that H citrina will give larger bloom sizes too.  H citrina based cultivars (with scape heights)  found in the parentage of many early daylilies include:

Ophir 50”,  Golden West 48”, Sir Michael Foster 48”, Hyperion 40” and Yellowstone 36”.

I looked for these foundation stock plants when I was researching plants to start my program with.  Many plants in my tall lines trace ancestry back to H citrina via these classic foundation plants.


RÖGNVALDUR

Viking series:  a Norwegian Viking commander who occupied the Bretagne region of France.
Mahieu Diploid 98-584 K
[(H citrina x ROSY LIGHTS) X PERSIAN PATTERN]
70 ML 6.5 NOC EXT VFR DOR 3 way branching (lowest branch at 42 inches) 24 buds,  Trumpet form, fertile both ways.

This is a very TALL daylily, but the semi-open trumpet blooms are out facing.  The outfacing habit is one that I have seen a need for ever since I began breeding for tall daylilies.  Lilium breeders have very specific registration guidelines for flower habit:  ((a) up-, (b) out- or (c) down-facing) blooms.  An upfacing daylily on a 6 foot scape will be of little interest to human gardeners, aerial insects will enjoy it though!

Another challenge when breeding tall daylilies is to get the palette into any area of the spectrum besides shades of yellow and orange. When Rögnvaldur was registered in 2003 there were very few daylilies in the 5-6 foot range with blooms in this color family. (The bitone flowers have smoky violet petals with a darker purple chevron band.  Sepals are several shades lighter than the petals.  Waxy substance with a creamy lemon to lime green throat.)  Branching is very well spaced up the scape, and I expect it will increase in a garden setting.  The three ancestors in Rögnvaldur's immediate ancestry:  H citrina, ROSY LIGHTS and PERSIAN PATTERN have all been key in producing height and great buds and branching in my program.  From observing three acres of seedlings and breeding extensively with H citrina I believe - based on phenotype - that both “Rosy Lights” and “Persian Pattern” are H citrina descendants, though their hybridizers did not list parentage in registration materials.  (aarg!)  If you are a hybridizer and your goal truly is to advance the genus:  please list your cultivar's parentage when you register plants.

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Here I am with the next generation out of Rögnvaldur, this is Rögnvaldursson Mahieu-Burris '08.
Rögnvaldur passes on the height as well as bud building, beautifully spaced branching (over 6X) and great color.  This scape matured to over 6'3" tall, and that was after being moved to Kentucky while in full bloom!

Several of Stout’s altissima based cultivars and their heights are: 
Challenger 48”, Autumn Minaret 66”, Chancellor 55”, Statuesque 60”

I used Stout's "Challenger" as a foundation plant, and the tallest registration I have bloomed out of that (altissima) line of breeding is PACK HUNTER at 50” tall, but the next generation in near 7 feet tall!

PACK HUNTER
Mahieu Diploid 98-470 F
[CHALLENGER X  (MONT BLANC x BLOODSTREAM)]
50 ML RE 7 FR NOC EXT, 5 way branching 38 buds 3 way Crispate Unusual Form

PACK HUNTER and its full sibling ROYAL FLYCATCHER  are two of the most vigorous growers and increasers I have seen.  Their bloodlines combine both H. altissima (via Challenger) and H. citrina lines.  The next generation out of this line produced the tallest daylily I have seen at nearly seven feet. (at right)  I need to get the outfacing bloom trait into this line and want to get other colors besides yellow, but I should easily be able to achieve oranges and red, and with Rögnvaldur I have the purples covered.  



References:

Daylilies, A. B. Stout 1986. Originally printed by Macmillan in 1934.
ISBN:  0-89831-028-8

This is the classic treatment of the daylily. Included is a history of the evolution of daylilies, containing descriptions and colored pictures of species, varieties, and many of the earliest cultivars. Also included is some cultural information.  If you want a working knowledge of the foundation species behind modern cultivars this is a "must read".  I cherish my copy.

A Passion for Daylilies - The Flowers and The People, Sydney Eddison, 1992.
ISBN: 0805026118

 Though out of print, try to find a used copy at one of these great Book Sellers:

Bluegrass Gardens will introduce the best of my tall lines probably beginning in the fall of 2007