Helleborus ‘COSEH 710’ Has Light Green Flowers With Reddish Pink Flushes

Summary: Helleborus ‘COSEH 710,’ a new cultivar by German helleborist Josef Heuger, has light green flowers with reddish pink flushes and dark green leaves.

Helleborus ‘COSEH 710’ image included in patent application filed Jan. 7, 2009, with United States Patent and Trademark Office: Josef Heuger, Public Domain, via U.S. Patent and Trademark Office

Helleborus ‘COSEH 710,’ a newly cultivated hellebore variety by German hellebore breeder Josef Heuger, has dark green leaves and a long natural blooming season of light green flowers with reddish pink flushes.

On Jan. 7, 2009, Josef Heuger filed an application with the United States Patent and Trademark Office for his plant invention, a newly cultivated variety of Helleborus niger x Helleborus lividus that he named Helleborus ‘COSEH 710.’ Primary examiner June Hwu reviewed the application. On June 8, 2010, the U.S. Patent and Trademark Office granted patent number PP21,063 for Helleborus ‘COSEH 710.’

‘COSEH 710’ numbers among the progeny of a cross-pollination program conducted January 2003 by the inventor. The cross-pollination concerned proprietary selections of unnamed, unpatented female Helleborus niger and male Helleborus lividus seedlings. The program took place in a controlled greenhouse environment at the Heuger family nursery, Heuger Gartenbaubetriebe, in Glandorf, Lower Saxony state, northwestern Germany.

In March 2006 the inventor discovered and selected a single flowering plant, now designated as ‘COSEH 710,’ from the program’s progeny. Propagation by divisions since March 2006 revealed the stable, true reproduction of the new variety’s distinctive characteristics over successive generations.

The application’s botanical details describe one-year-old plants, grown outdoors during winter in 15-centimeter (5.9-inch) containers. Day temperatures during production ranged from 5 to 32 degrees Celsius (41 to 89.6 degrees Fahrenheit). The night temperature range was from 1 degree to 25 degrees C (33.8 to 77 degrees F).

Helleborus ‘COSEH 710’ presents a mounded, outwardly spreading, upright shape. Its growth habit is vigorous. Plant height ranges from 30 to 35 centimeters (11.81 to 13.77 inches). Helleborus ‘COSEH 710’ spreads to a diameter range of about 50 to 60 centimeters (19.68 to 23.62 inches).

Palmately compound leaves consist of five serrated leaflets per leaf. Leaflet shape is roughly ovate (Latin: ovatus, “egg-shaped”). Sharply pointed leaflet tips are described as acute. The texture of upper and lower surfaces is leathery and smooth.

Leaflet length ranges from about 7 to 14 centimeters (2.75 to 5.51 inches). Width range is from about 2.5 to 6 centimeters (0.98 to 2.36 inches).

Upper surfaces of fully developed leaves are dark green (Royal Horticultural Society color 147A), with brown green (RHS 146B) venation. Lower surfaces of fully developed leaves is brown green (RHS 191A), with brown purple (RHS 187A) veins.

The new cultivar’s freely flowering habit yields about 15 to 25 flowers per plant. Helleborus ‘COSEH 710’ presents a long, natural flowering season spanning December to March. Each flower, which is persistent, has a longevity of about three weeks.

Helleborus ‘COSEH 710’ flowers exude a moderate fragrance that is pleasantly detectable. With no observable petals, the floral arrangement comprises a single whorl of about five sepals.

Sepal length is about 4 centimeters (1.57 inches). Sepal depth measures about 2 to 3 centimeters (0.78 to 1.18 inches).

Sepal shape is broadly ovate to rounded, with rounded tips. Margins are smooth, termed as entire. Upper and lower surfaces are satiny smooth.

Lower and upper surfaces of fully opened flowers are light green (RHS 144B) with red pink (RHS 51C) flushes. With development, upper surface color becomes brown green (RHS 146B) with red pink (RHS 51C) flushes.

Helleborus ‘COSEH 710’ is available commercially as Helleborus x ballardiae ‘HGC Pink Frost'®. The crossing of Helleborus niger with Helleborus lividus is designated botanically as Helleborus x ballardiae. The hybrid name honors British hellebore hybridizer Helen Ballard. The Helleborus Gold Collection (HGC®) is Heuger's symbol of quality. Selections in the series are winter hardy and beautifully floriferous over a long, natural blooming season.

Helleborus ‘COSEH 710’ is a good garden performer, with easy tolerance of rain and wind. Acceptable temperatures for Helleborus ‘COSEH 710’ range from about minus 10 to about 36 degrees C (14 to 96.8 degrees F).

Helleborus ‘COSEH 710’ plantings contribute appealing colors and attractive silhouettes to indoor and outdoor spaces. The cultivated variety’s pleasant fragrance and lengthy flowering embellish gardens during the critical seasons of winter and early spring.

Helleborus ‘Pink Frost,’ The Greenery Nursery and Garden Shop, Turlock, Stanislas County, Central Valley, California, Feb. 26, 2013: The Greenery Nursery and Garden Shop (The Greenery Nursery), CC BY 2.0, via Flickr

Acknowledgment

My special thanks to talented artists and photographers/concerned organizations who make their fine images available on the internet.

Image credits:

Helleborus ‘COSEH 710’ image included in patent application filed Jan. 7, 2009, with United States Patent and Trademark Office: Josef Heuger, Public Domain, via U.S. Patent and Trademark Office @ http://pdfpiw.uspto.gov/.piw?PageNum=0&docid=PP021063

Helleborus ‘Pink Frost,’ The Greenery Nursery and Garden Shop, Turlock, Stanislas County, Central Valley, California, Feb. 26, 2013: The Greenery Nursery and Garden Shop (The Greenery Nursery), CC BY 2.0, via Flickr @ https://www.flickr.com/photos/greenerynsy/8510384151/

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