plant named ‘Flevo 21-13-371’

Abstract

A new and distinct cultivar of Helleborus plant named ‘Flevo 21-13-371’, characterized by its upright and mounding plant habit; relatively vigorous growth habit; green-colored leaves; freely flowering habit; dark purplish red-colored flower sepals; and good garden performance.

Description

Botanical designation: Helleborus x hybridus X Helleborus sternii.

Cultivar denomination: ‘FLEVO 21-13-371’.

CROSS-REFERENCED TO CLOSELY-RELATED APPLICATIONS

A European Community Plant Breeder's Rights application for the instant plant was filed by the Applicant/Assignee of the instant application, FlevoFlora B.V. of Marknesse, The Netherlands on Sep. 30, 2024, application number 2024/2293. Foreign priority is not claimed to this European Community Plant Breeder's Rights application.

BACKGROUND OF THE INVENTION

The present invention relates to a new and distinct cultivar of Helleborus plant, botanically known as Helleborus x hybridus X Helleborus sternii, commonly referred to as an interspecific hybrid Hellebore and hereinafter referred to by the name ‘Flevo 21-13-371’.

The new Helleborus plant is a product of a planned breeding program conducted by the Inventor in Marknesse, The Netherlands. The objective of the breeding program was to create new uniformly mounding and freely-flowering Helleborus plants with attractive leaves and flowers.

The new Helleborus plant originated from a cross-pollination conducted by the Inventor in Marknesse, The Netherlands in December 2021 of a proprietary selection of Helleborus x hybridus identified as code number 2097, not patented, as the female, or seed, parent with an unidentified proprietary selection of Helleborus sternii, not patented, as the male, or pollen, parent. The new Helleborus plant was discovered and selected by the Inventor as a single flowering plant from within the progeny of the stated cross-pollination grown in a controlled greenhouse environment in Marknesse, The Netherlands in January 2023.

Asexual reproduction of the new Helleborus plant by in vitro meristem culture in a controlled greenhouse environment in Marknesse, The Netherlands since May 2023, has shown that the unique features of this new Helleborus plant are stable and reproduced true to type in successive generations.

SUMMARY OF THE INVENTION

Plants of the new Helleborus have not been observed under all possible combinations of environmental conditions and cultural practices. The phenotype of the new Helleborus plant may vary somewhat with variations in environmental conditions such as temperature and light intensity without, however, any variance in genotype of the new Helleborus plant.

The following traits have been repeatedly observed and are determined to be the unique characteristics of ‘Flevo 21-13-371’. These characteristics in combination distinguish ‘Flevo 21-13-371’ as a new and distinct Helleborus plant:

• • 1. Upright and mounding plant habit.
  • 2. Relatively vigorous growth habit.
  • 3. Green-colored leaves.
  • 4. Freely flowering habit.
  • 5. Dark purplish red-colored flower sepals.
  • 6. Good garden performance.

Plants of the new Helleborus differ primarily from plants of the female parent selection in the following characteristics:

• • 1. Plants of the new Helleborus are larger than plants of the female parent selection.
  • 2. Plants of the new Helleborus are more freely flowering than plants of the female parent selection.
  • 3. Flower sepals of plants of the new Helleborus are purplish red in color whereas flower sepals of plants of female parent selection are reddish purple in color.

Plants of the new Helleborus can be compared to plants of Helleborus x ericsmithii X Helleborus x hybridus ‘FLEVO 20-11-034’, disclosed in a U.S. Plant patent application Ser. No. 19/224,790, filed concurrently. In side-by-side comparisons, plants of the new Helleborus differ from plants of ‘FLEVO 20-11-034’ in the following characteristics:

• • 1. Plants of the new Helleborus are more compact than plants of ‘FLEVO 20-11-034’.
  • 2. Plants of the new Helleborus have smaller leaves than plants of ‘FLEVO 20-11-034’.
  • 3. Plants of the new Helleborus are more freely flowering than plants of ‘FLEVO 20-11-034’.
  • 4. Plants of the new Helleborus have smaller flowers than plants of ‘FLEVO 20-11-034’.

BRIEF DESCRIPTION OF THE PHOTOGRAPHS

The accompanying colored photographs illustrate the overall appearance of the new Helleborus plant showing the colors as true as it is reasonably possible to obtain in colored reproductions of this type. Colors in the photographs may differ slightly from the color values cited in the detailed botanical description which accurately describe the colors of the new Helleborus plant.

The photograph on the first sheet (FIG. 1) is a side perspective view of a typical flowering plant of ‘Flevo 21-13-371’ grown in a container.

The photograph on the second sheet (FIG. 2) is a close-up view of a typical flowering plant of ‘Flevo 21-13-371’.

DETAILED BOTANICAL DESCRIPTION

The aforementioned photographs and following observations, measurements and values describe plants grown in 19-cm containers during the winter in a glass-covered greenhouse in Marknesse, The Netherlands and under cultural practices typical of commercial Helleborus production. During the production of the plants, day temperatures ranged from 12° C. to 31° C. and night temperatures ranged from 3° C. to 16° C. Plants were 13 months old when the photographs and the description were taken. In the following description, color references are made to The Royal Horticultural Society Colour Chart, 2015 Edition, except where general terms of ordinary dictionary significance are used.

• Botanical classification: Helleborus x hybridus X Helleborus sternii ‘Flevo 21-13-371’.
• Parentage:
  • • Female, or seed, parent.—Proprietary selection of Helleborus x hybridus identified as code number 2097, not patented.
    • Male, or pollen, parent.—Unidentified proprietary selection of Helleborus sternii, not patented.
• Propagation:
  • • Type.—By in vitro meristem culture.
    • Time to initiate roots, winter.—About 46 days at temperatures about 12° C.
    • Time to produce a rooted young plant, winter.—About 20 weeks at temperatures about 2° C. to 14° C.
    • Root description.—Fleshy, variable in thickness; typically white to greenish brown in color, actual color of the roots is dependent on substrate composition, water quality, fertilizer type and formulation, substrate temperature and physiological age of roots.
    • Rooting habit.—Not freely branching; sparse.
• Plant description:
  • • Plant and growth habit.—Herbaceous perennial; upright and mounding plant habit; overall plant shape, roughly flattened globular; relatively vigorous growth habit and moderate growth rate; leaves arranged in basal rosettes; flowers held within and above the foliar plane.
    • Plant height, soil level to top of foliar plane.—About 19.7 cm.
    • Plant height, soil level to top of floral plane.—About 22.2 cm.
    • Plant diameter (area of spread).—About 26.1 cm.
• Leaf description:
  • • Arrangement.—Leaves arranged alternately in a basal rosette; leaves palmately compound with typically three to five leaflets per leaf.
    • Leaf length.—About 17.2 cm.
    • Leaf width.—About 20.6 cm.
    • Leaflet length.—About 8.9 cm to 13.1 cm.
    • Leaflet width.—About 4.3 cm.
    • Leaf shape.—Palmately compound; roughly reniform in outline.
    • Leaflet shape.—Ovate.
    • Leaflet apex.—Acute.
    • Leaflet base.—Attenuate.
    • Leaflet margin.—Crenate to serrate; slightly undulate.
    • Leaflet texture and luster, upper and lower surfaces.—Smooth, glabrous; leathery; glossy.
    • Leaflet venation pattern.—Pinnate.
    • Leaflet color.—Developing leaflets, upper surface: Close to 136A; venation, close to 136B. Developing leaflets, lower surface: Close to 143C; venation, close to 144C. Fully expanded leaflets, upper surface: Close to 143B; venation, close to 143A. Fully expanded leaflets, lower surface: Close to 144B; venation, close to 144C.
    • Petioles.—Length: About 11.3 cm. Diameter: About 4 mm to 7 mm. Texture, upper and lower surfaces: Smooth, glabrous. Color, upper surface: Close to 143A. Color, lower surface: Close to 143B.
• Flower description:
  • • Flower shape and habit.—Single rotate cyanthiform flowers arranged in loosely-branched terminal and axillary cymes; freely flowering habit with typically about ten to twelve flowers developing per cyme and about 144 flowers developing during the first flowering season; flowers face outwardly to nodding.
    • Fragrance.—None detected.
    • Natural flowering season.—Plants begin flowering about nine months after planting young plants; flower continuously from the end of January to the end of April in The Netherlands.
    • Flower longevity on the plant.—About nine days; sepals are persistent and other flower parts are not persistent.
    • Flower buds.—Length: About 2 cm. Diameter: About 1.1 cm. Shape: Broadly ovoid. Texture and luster: Smooth, glabrous; matte. Color: Close to 59A.
    • Inflorescence height.—About 21.2 cm.
    • Inflorescence diameter.—About 21.8 cm.
    • Flower diameter.—About 5.9 cm.
    • Flower depth (height).—About 2 cm.
    • Petals.—None observed; transformed into nectaries.
    • Sepals.—Quantity and arrangement: About five arranged in a single whorl. Length: About 2.1 cm to 2.4 cm. Width: About 1.7 cm. Shape: Obovate. Apex: Obtuse. Base: Cuneate. Margin: Entire; slightly undulate. Texture and luster, upper and lower surfaces: Smooth, glabrous; matte. Color: When opening and fully opened, upper surface: Close to 59A; color becoming closer to 60B with margins, close to between 183A and 184A, with subsequent development. When opening and fully opened, lower surface: Close to 59B; color becoming closer to 60B with margins, close to between 183A and 184A, with subsequent development.
    • Peduncles.—Length: About 13.7 cm. Diameter: About 5 mm to 10 mm. Texture and luster: Smooth, glabrous; moderately glossy. Color: Close to 144B flushed with close to N187B.
    • Pedicels.—Length: About 1.4 cm to 2.3 cm. Diameter: About 3 mm. Texture and luster: Smooth, glabrous; moderately glossy. Color: Close to 187C with fine dots, close to 143A.
    • Reproductive organs.—Stamens: Quantity per flower: About 90.Filament length: About 1.5 cm. Filament color: Close to 186B; distally, close to 155D. Anther shape: Reniform; basifixed. Anther size: About 2 mm by 3 mm. Anther color: Close to 2B. Pollen amount: Abundant. Pollen color: Close to 4D. Pistils: Quantity per flower: About five. Pistil length: About 1.1 cm. Stigma diameter: About 0.2 mm. Stigma shape: Club-shaped. Stigma color: Close to 145C. Style length: About 1 cm. Style color: Close to 184A. Ovary color: Close to 187B.
    • Nectaries.—Quantity per flower: About ten. Length: About 7 mm. Width: About 2.2 mm. Shape: Tubular, flattened. Texture and luster, inner and outer surfaces: Smooth, glaucous; matte. Color: When opening, inner and outer surfaces: Close to N144B. Fully opened, inner and outer surfaces: Close to 154A and distally, close to 150B; main color becoming closer to 150A with subsequent development. Seeds and fruits: To date, seed and fruit development have not been observed on plants of the new Helleborus.
• Garden performance & temperature tolerance: Plants of the new Helleborus have been observed to have good garden performance and to tolerate rain and wind. Plants of the new Helleborus are suitable for USDA Hardiness Zones 4 to 9 and have been observed to tolerate high temperatures about 36° C.
• Pathogen & pest resistance: To date, plants of the new Helleborus have not been observed to be resistant to pathogens and pests common to Helleborus plants.

Claims

1. A new and distinct Helleborus plant named ‘Flevo 21-13-371’ as herein illustrated and described.