Denomination: 'Youmenine'
Trade name: Romance
Botanical Name: Hydrangea macrophylla
Applicant/Holder: Irie, Ryoji
3-7 Narutaki Honmachi Ukyoku
Ukyo Ku, Kyoto
Breeder: Ryoji Irie, Ukyo Ku, Kyoto, Japan
Agent in Canada: BioFlora Inc.
38723 Fingal Line
R.R. #1
St. Thomas, Ontario
N5P 3S5
Tel: 519-631-6241
Application Date: 2005-06-02
Application Number: 05-4937
Date abandoned: 2012-05-04

Variety Description

Variety used for comparison: 'Youmethree' (Emotion)

Summary: The plants of 'Youmenine' are shorter than the plants of 'Youmethree'. The leaf blade of 'Youmenine' is shorter and narrower than the leaf blade of 'Youmethree'. The leaf blade margin of 'Youmenine' has shallow incisions while the leaf blade of 'Youmethree' has medium depth incisions. The sterile flower of 'Youmenine' has darker blue pink sepal colour than the sterile flower of 'Youmethree'.


PLANT: non-climbing, broad upright growth habit
STEM: no fasciation, green, medium number of dark red lenticels in spring

LEAF: no lobing, short tip, rounded base, shallow margin incisions, no variegation, dark green, weak glossiness on upper side, no blistering

INFLORESCENCE: early flowering, globular shape, fertile flowers slightly inconspicuous
STERILE FLOWER: double, medium overlapping of sepals
STERILE FLOWER SEPALS : no incisions on margin, outer sepals light blue pink (RHS 62C) with lighter blue pink (RHS 62D) at mid vein area, inner sepals light blue pink (RHS 62B), central sepals yellow green (RHS 2D).

Origin & Breeding History: The hydrangea variety 'Youmenine' originated from a pollination made in Kyoto, Japan in May 1993. The female parent was an unnamed plant from the breeder's collection and the male parent was the variety 'Sumidanohanabi'. The variety was selected from the cross in June 1994, based on criteria for flower colour, flower appearance and inflorescence development traits. Propagation of the variety by vegetative cuttings was first conducted in the spring of 1995 in Kyoto, Japan.

Tests & Trials: Trials for 'Youmenine' were conducted in a polyhouse during the winter and spring of 2010 in St. Thomas, Ontario. The trial included 10 plants of the candidate variety and reference variety. All plants were grown from unrooted cuttings that were rooted in the early spring of 2009 and grown in St. Catharines, Ontario. All plants were finished in St. Thomas, Ontario in the spring of 2010. Observations and measurements were taken from 10 plant parts of each variety on May 6, 2010. All colour determinations were made using the 2007 Royal Horticultural Society (RHS) Colour Chart.

Comparison tables for 'Youmenine' with reference variety 'Youmethree'

Plant height (cm)

  'Youmenine' 'Youmethree'
mean 17.4 24.4
std. deviation 1.70 1.94

Leaf blade length (cm)

  'Youmenine' 'Youmethree'
mean 9.5 11.8
std. deviation 0.48 0.50

Leaf blade width (cm)

  'Youmenine' 'Youmethree'
mean 6.9 9.5
std. deviation 0.24 0.47

Inflorescence diameter (cm)

  'Youmenine' 'Youmethree'
mean 14.2 17.3
std. deviation 1.39 1.02

Colour of sepal on sterile flower (RHS)

  'Youmenine' 'Youmethree'
outer sepal 62C with 62D at midvein 69B-C
inner sepal 62B 69A
central sepal 2D 4D, 1C when newly opened

Click on image for larger view
Hydrangea: 'Youmenine' (left) with reference variety 'Youmethree' (right)

Click on image for larger view
Hydrangea: 'Youmenine' (left) with reference variety 'Youmethree' (right)

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