The anatomical structure of the ‘SIT Pink Power’ flower. The flowers of ‘SIT Pink Power’, ‘Pretty Woman’, and ‘Ruby Throat’ during their blooming period (A–C). The anatomic structure of the flowers of ‘SIT Pink Power’, ‘Pretty Woman’, and ‘Ruby Throat’ (D–F).
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Hemerocallis fulva L. is a perennial herbaceous species belonging to the Asphodelaceae family. It is characterized by its elegant growth habit, diverse range of flower colors and forms, and significant ornamental value. Because of these attributes, it is commonly used as an ornamental plant in landscaping and flower beds and is considered one of the most popular perennial herbaceous ornamental plants (Cameron et al. 2000; Li et al. 2021). In recent years, numerous Hemerocallis cultivars have been developed and introduced, exhibiting a wide array of floral characteristics. For example, ‘Xuan Cai Jin Huang’ (from selfing of ‘Da Jin Bei’) produces bright yellow flowers with large diameters exceeding 18 cm (Li et al. 2022); ‘Ying Huang’, derived from H. minor by vegetative propagation, features vivid yellow flowers (Han et al. 2024); ‘Jinjiuhong’, a hybrid of ‘Suzie Wong’ × ‘Stella De Oro’, bears wine-red fragrant flowers (Sun et al. 2024), and ‘Zaoxia’ presents orange-brown flowers with spotted petals (Ma and Shi 2024).
According to the database of the American Daylily Society, more than 100,000 Hemerocallis cultivars have been officially registered. They exhibit a wide range of variation in blooming periods (from early May to late October), flower colors (including nearly white, soft yellow, orange, pink, bright red, green, deep red, purple, neon pink, nearly pure blue, and various color combinations and multicolor patterns), scape heights (ranging from 30 to 150 cm), and flower diameters (measuring from 5 to 40 cm). To enrich the ornamental germplasm resources, we report the development of a new cultivar, ‘SIT Pink Power’ characterized by its light pink flowers.
In 2007, we introduced ‘Ruby Throat’ and ‘Pretty Woman’ Xuan grass seedlings from the United States and planted them in the nursery of Shanghai University of Applied Sciences Fengxian Campus (121°30′38″N, 30°50′33″E) in the spring. In 2008, artificial pollination was carried out using ‘Ruby Throat’ as the female parent and ‘Pretty Woman’ as the male parent, and seeds were collected in August of the same year. These seeds were sown in pots and placed in a greenhouse in 2009. In 2012, an outstanding individual was identified among the F1 progeny, exhibiting bright rose red (N45D) outer petals and pink (50D) inner petals. The Royal Horticultural Society (2007) Color Chart was used to record flower colors. From 2017–19, this individual was propagated through division to establish a stable plant population. Between 2017 and 2019, comprehensive observations and trait comparisons were conducted. The strain demonstrated superior stability, uniformity, and distinctiveness in terms of flower color, flowering time, and plant morphology. Due to its overall pink hue, it was officially named ‘SIT Pink Power’. The cultivar was registered with the American Daylily Society in 2019 under registration number 25822.
‘SIT Pink Power’ is a cultivar of H. fulva cultivars characterized by relatively short plant clusters, with leaf clusters extending at an oblique angle, dark green, glabrous, linear-shaped leaves with sharp edges and a slightly trough-like appearance. The flowers are round or cup-shaped, single-petaled, and bicolor, with distinct coloration between the inner and outer petals. The overall floral color is pink, exhibiting bright and attractive hues, a prolonged flowering period, and significant potential for use in landscape design. Between 2017 and 2019, ‘SIT Pink Power’, ‘Ruby Throat’, and ‘Pretty Woman’ were evaluated using a randomized complete block design, with 30 plants per replicate, totaling 90 plants. Phenotypical measurements were conducted using 30 randomly selected plants from each genotype, with fully open flowers. Statistical analysis was conducted using SPSS 27.0 software (Lenovo, Beijing, China).
‘SIT Pink Power’ was selected from the hybrid offspring of ‘Pretty Woman’ and ‘Ruby Throat’ (Fig. 1). ‘SIT Pink Power’ is a bicolor flower with different colors for the inner and outer petals. The inner petal is a bright rose red (N45D), while the outer petal is pink (50D). The flower as a whole is pink with yellow flower throat (3A) (Fig. 1A and 1D). Compared with its parents: ‘Pretty Woman’ is light pink (36D) and ‘Ruby Throat’ is deep rose red (45A), the colors are more rich and novel. The plant height of ‘SIT Pink Power’ is 33.51 ± 0.32 cm, significantly lower than that of its parents ‘Pretty Woman’ (35.77 ± 0.15 cm) and ‘Ruby Throat’ (35.53 ± 0.31 cm) (Table 1). Compared with the leaves of ‘SIT Pink Power’ (length: 27.62 ± 0.36 cm, width: 1.92 ± 0.13 cm), the leaves of ‘Pretty Woman’ (length: 30.44 ± 0.44 cm, width: 2.69 ± 0.24 cm) and ‘Ruby Throat’ (length: 30.71 ± 0.19 cm, width: 2.49 ± 0.36 cm) are relatively wider and longer. The diameter of the flowers of ‘SIT Pink Power’ is 14.54 ± 0.27 cm, significantly larger than that of ‘Pretty Woman’ (13.20 ± 0.31 cm) and ‘Ruby Throat’ (12.52 ± 0.28 cm), and has better ornamental value. The scape length of ‘SIT Pink Power’ is 57.00 ± 2.65 cm, which is significantly lower than that of its parents, ‘Pretty Woman’ (74.00 ± 0.20 cm) and ‘Ruby Throat’ (74.07 ± 0.12 cm). In addition, the inner petal length and width, and outer petal length of ‘SIT Pink Power’ (inner petal length: 9.22 ± 0.10 cm, inner petal width: 5.41 ± 0.18 cm, outer petal length: 9.74 ± 0.15 cm) showed no significant difference compared with ‘Ruby Throat’ (inner petal length: 9.50 ± 0.23 cm, inner petal width: 5.68 ± 0.22 cm, outer petal length: 9.46 ± 0.33 cm), but were significantly longer than those of ‘Pretty Woman’ (inner petal length: 8.56 ± 0.31 cm, inner petal width: 4.54 ± 0.34 cm, outer petal length: 8.50 ± 0.39 cm); the outer petal width of ‘SIT Pink Power’ (3.65 ± 0.28 cm) was significantly wider than that of ‘Pretty Woman’ (2.31 ± 0.29 cm) and ‘Ruby Throat’ (2.66 ± 0.22 cm). Both the inner and outer petals of ‘SIT Pink Power’ show significant differences in length and width. ‘SIT Pink Power’ begins to bloom in early June and ends in early July, with a significantly longer flowering period than ‘Pretty Woman’ (mid-June to late June) and ‘Ruby Throat’ (mid-June to early July).
Citation: HortScience 60, 12; 10.21273/HORTSCI19002-25
‘SIT Pink Power’ demonstrates strong adaptability and exhibits excellent performance when cultivated in open fields in the Shanghai region of China. It is well suited for growth in environments with ample sunlight and no risk of severe waterlogging. During seedling propagation, large clumps from mature plants are divided into groups containing two or three buds each. The optimal planting periods are autumn or early spring. Initially, the entire plant is excavated, lateral buds are exposed, roots are pruned to a length of 10 to 15 cm, and leaves are trimmed to ∼15 cm in length. Each planting hole accommodates only one clump, and the roots must be fully covered with soil, which should then be firmly compacted.
‘SIT Pink Power’ exhibits excellent heat tolerance and disease resistance, making it suitable for cultivation in open fields in the Shanghai region of China. This variety thrives in full sunlight and nutrient-rich soil and can be used as an ornamental plant in gardens or as part of public green spaces. It is well suited for planting along garden borders, in green belts, or as a potted plant. Owing to its distinctive color, ‘SIT Pink Power’ can be effectively combined with darker-colored gladiolus varieties such as ‘Bela Lugosi’ to prolong the overall blooming season, or paired with Verbena bonariensis L. to enhance visual appeal.
Inquiries about research or request for ‘SIT Pink Power’ plant materials can be made to Dr. Luan (E-mail: ldt@sit.edu.cn) at College of Ecological Technology and Engineering, Shanghai Institute of Technology, Shanghai, China.
The anatomical structure of the ‘SIT Pink Power’ flower. The flowers of ‘SIT Pink Power’, ‘Pretty Woman’, and ‘Ruby Throat’ during their blooming period (A–C). The anatomic structure of the flowers of ‘SIT Pink Power’, ‘Pretty Woman’, and ‘Ruby Throat’ (D–F).
Contributor Notes
D.L. is the corresponding author. E-mail: ldt@sit.edu.cn.
The anatomical structure of the ‘SIT Pink Power’ flower. The flowers of ‘SIT Pink Power’, ‘Pretty Woman’, and ‘Ruby Throat’ during their blooming period (A–C). The anatomic structure of the flowers of ‘SIT Pink Power’, ‘Pretty Woman’, and ‘Ruby Throat’ (D–F).
