Horticulture Industrial Research Division, Gyeonggi-do Agricultural Research & Extension Services1
A standard rose cultivar, ‘Love Letter’ was selected for cut flower from the progenies of a cross between ‘Red Giant’ and ‘Ensemble’ by the rose breeding team of the Gyeonggi-do Agricultural Research & Extension Services (GARES) in 2011. A standard rose cultivar ‘Red Giant’ with red colored (RHS Red Group 45C) petals and 1.8 prickles per stems of 10 cm was used as a mother plant. A standard rose cultivar ‘Ensemble’ with white and red purple colored (RHS White Group 155C + RHS Red Group N57B) petals and 2.4 prickles per stems of 10 cm was used as a pollen parent. ‘Love Letter’ was crossed in 2007 and seedlings were produced. After tests of specific characters from 2008 to 2011, this cultivar was finally selected and named. As a standard type with large sized flower, it has red colored (RHS Red Group 46A) petals with 9.3 cm flower diameter and 32.4 petals per flower. Vase life of this cultivar could be as long as 12 days. It takes 43 days from pruning to blooming and cut flower productivity was 152 stems/m2 in a year. The stems of cut flower have no thorn and the length is about with 70.5 cm. When this cultivar grew below 15°C and 1,000 lux, the petals color became dark red in winter season. ‘Love Letter’ was registered as a new cultivar on Korea Seed & Variety Service (KSVS) with No. 4482 on May 8, 2013.
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