USPP36772P2

USPP36772P2 - Helleborus plant named ‘Borusmura25’

Info

Publication number: USPP36772P2
Application number: US18/955,808
Authority: US
Inventors: Miyoko Hattori
Original assignee: Individual
Current assignee: Individual
Priority date: 2024-11-21
Filing date: 2024-11-21
Publication date: 2025-06-24
Anticipated expiration: 2044-11-21

Abstract

A new and distinct cultivar of Helleborus plant named ‘Borusmura25’, characterized by its relatively compact, upright to outwardly spreading and mounding plant habit; moderately vigorous to vigorous growth habit; deeply serrated leaflets that have dark green-colored upper surfaces that are densely covered with light green-colored speckles and lower surfaces that are greyish green in color; freely flowering habit; yellowish green-colored flowers with purplish red-colored margins; and good garden performance.

Description

Botanical designation: Helleborus x sternii (Helleborus argutifolius X Helleborus lividus).

Cultivar denomination: ‘BORUSMURA25’.

BACKGROUND OF THE INVENTION

The present invention relates to a new and distinct cultivar of Helleborus plant, botanically known as Helleborus x sternii (Helleborus argutifolius X Helleborus lividus), commonly referred to as an interspecific hybrid Hellebore and hereinafter referred to by the name ‘Borusmura25’.

The new Helleborus plant is a product of a planned breeding program conducted by the Inventor in Kiyose, Japan. 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 Toyko, Japan in March, 2016 of an unidentified proprietary selection of Helleborus argutifolius, not patented, as the female, or seed, parent with an unidentified proprietary selection of Helleborus lividus, 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 Kiyose, Japan in March, 2018.

Asexual reproduction of the new Helleborus plant by divisions in a controlled greenhouse environment in Kiyose, Japan since March, 2018, 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 ‘Borusmura25’. These characteristics in combination distinguish ‘Borusmura25’ as a new and distinct Helleborus plant:

- 1. Relatively compact, upright to outwardly spreading and mounding plant habit.
- 2. Moderately vigorous to vigorous growth habit.
- 3. Deeply serrated leaflets that have dark green-colored upper surfaces that are densely covered with light green-colored speckles and lower surfaces that are greyish green in color.
- 4. Freely flowering habit.
- 5. Yellowish green-colored flowers with purplish red-colored margins.
- 6. Good garden performance.

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

- 1. Leaflets of plants of the new Helleborus have deeply serrated margins whereas leaflets of plants of the female parent selection have non-serrated margins.
- 2. Leaflets of plants of the new Helleborus are dark green in color and are densely covered with light green-colored speckles whereas leaflets of plants of the female parent selection are greyish green in color without speckles.
- 3. Leaflet venation of plants of the new Helleborus is light green and purplish red in color whereas leaflet venation of plants of female parent selection is darker green in color.

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

- 1. Leaflets of plants of the new Helleborus have deeply serrated margins whereas leaflets of plants of the male parent selection have shallowly serrated margins.
- 2. Leaflets of plants of the new Helleborus are dark green in color and are densely covered with light green-colored speckles whereas leaflets of plants of the male parent selection are green in color flushed with white and without speckles.
- 3. Leaflet venation of plants of the new Helleborus is light green and purplish red in color whereas leaflet venation of plants of male parent selection is greyed white in color.

Plants of the new Helleborus can be compared to plants of Helleborus niger X Helleborus lividus ‘COSEH 700’, disclosed in U.S. Plant Pat. No. 21,003. In side-by-side comparisons, plants of the new Helleborus differ from plants of ‘COSEH 700’ in the following characteristics:

- 1. Leaflets of plants of the new Helleborus have more deeply serrated margins than leaflets of plants of ‘COSEH 700’.
- 2. Leaflets of plants of the new Helleborus are dark green in color and are densely covered with light green-colored speckles whereas leaflets of plants of ‘COSEH 700’ are solid dark green in color and without speckles.
- 3. Leaflet venation of plants of the new Helleborus is light green and purplish red in color whereas leaflet venation of plants of ‘COSEH 700’ are medium green in color.

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 ‘Borusmura25’ grown in a container.

The photograph on the second sheet (FIG. 2 ) is a close-up view of a typical flowering plant of ‘Borusmura25’.

DETAILED BOTANICAL DESCRIPTION

The aforementioned photographs and following observations, measurements and values describe plants grown during the late winter in an outdoor nursery in Smoketown, Pennsylvania and under cultural practices typical of commercial Helleborus production. During the production of the plants, day temperatures ranged from 17° C. to 22° C., night temperatures ranged from 5° C. to 10° C. and light levels ranged from 30 to 70 klux. Plants were 1.75 years old when the photographs and the description were taken. In the following description, color references are made to The Royal Horticultural Society Colour Chart, Sixth Edition, except where general terms of ordinary dictionary significance are used.

Botanical classification: Helleborus x sternii (Helleborus argutifolius X Helleborus lividus) ‘Borusmura25’.
Parentage:
- - Female, or seed, parent.—Unidentified proprietary selection of Helleborus argutifolius, not patented.
  - Male, or pollen, parent.—Unidentified proprietary selection of Helleborus lividus, not patented.
Propagation:
- - Type.—By in vitro meristem culture.
  - Time to initiate roots.—About three to four weeks at soil temperatures about 20° C. and ambient temperatures about 22° C.
  - Time to produce a rooted young plant.—About six to eight weeks at soil temperatures about 20° C. and ambient temperatures about 22° C.
  - Root description.—Fleshy, medium in thickness; typically white to dark 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.—Moderate branching; medium density.
Plant description:
- - Plant and growth habit.—Herbaceous perennial; relatively compact, upright to outwardly spreading and mounding plant habit; overall plant shape, inverted triangle; moderately vigorous to vigorous growth habit and moderate growth rate; leaves arranged in basal rosettes.
  - Plant height, soil level to top of foliar plane.—About 20 cm.
  - Plant height, soil level to top of floral plane.—About 20 cm.
  - Plant diameter (area of spread).—About 45 cm.
Leaf description:
- - Arrangement.—Leaves arranged alternately in a basal rosette; leaves palmately compound with typically three leaflets per leaf.
  - Leaf length.—About 14 cm to 16 cm.
  - Leaf width.—About 8 cm to 10 cm.
  - Leaflet length.—About 6 cm to 10 cm.
  - Leaflet width.—About 4 cm to 6 cm.
  - Leaf shape.—Compound trifoliate.
  - Leaflet shape.—Lanceolate to narrowly elliptic.
  - Leaflet apex.—Acute.
  - Leaflet base.—Center leaflet, attenuate; lateral leaflets, oblique.
  - Leaflet margin.—Deeply serrate.
  - Leaflet texture and luster, upper and lower surfaces.—Smooth, glabrous; leathery; matte.
  - Leaflet venation pattern.—Pinnate and reticulate.
  - Leaflet color.—Developing leaflets, upper surface: Close to NN155C with speckles, close to 127A. Developing leaflets, lower surface: Close to N77C. Fully expanded leaflets, upper surface: Close to 136A with densely speckled with close to 130D; midvein, proximally, close to 61A and distally, close to 139A; lateral venation, similar to lamina colors. Fully expanded leaflets, lower surface: Close to 194B; midvein, proximally, close to 71D and distally, close to 191A; lateral venation, close to 194B.
  - Petioles.—Length, fully expanded leaflets: About 5 cm to 7 cm. Diameter, fully expanded leaflets: About 3 mm to 5 mm. Strength: Strong. Texture and luster, upper and lower surfaces: Smooth, glabrous; matte and waxy. Color, upper surface: Close to N77A speckled with close to 149D. Color, lower surface: Close to N77A speckled with close to 138D.
Flower description:
- - Flower shape and habit.—Single rotate cyanthiform flowers arranged in terminal and axillary cymes; freely flowering habit with typically about eight to ten flowers developing per cyme and about 180 to 200 flowers developing during the flowering season; flowers face outwardly to drooping.
  - Fragrance.—None detected.
  - Natural flowering season.—Plants flower continuously throughout February and March in Pennsylvania.
  - Flower longevity on the plant.—About three weeks; sepals are persistent and other flower parts are not persistent.
  - Flower buds.—Length: About 1.5 cm to 2 cm. Diameter: About 1 cm to 1.5 cm. Shape: Ovoid. Texture and luster: Smooth, glabrous; matte. Color: Close to 145D; at the marginal edges, close to 71A to 71B.
  - Inflorescence height.—About 18 cm to 22 cm.
  - Inflorescence diameter.—About 8 cm to 10 cm.
  - Flower diameter.—About 4 cm to 5 cm.
  - Flower depth (height).—About 2 cm to 3 cm.
  - Petals.—None observed; transformed into nectaries.
  - Sepals.—Quantity and arrangement: About five or six arranged in a single whorl. Length: About 2.5 cm to 3 cm. Width: About 2 cm to 2.5 cm. Shape: Oval. Apex: Obtuse. Base: Acute. Margin: Finely serrate. Texture and luster, upper and lower surfaces: Smooth, glabrous; matte. Color: When opening, upper surface: Close to 144D speckled with close to N79B. When opening, lower surface: Close to 142A; marginal edges, close to 70A to 70B. Fully opened, upper surface: Close to 142C; marginal edges, close to 71A. Fully opened, lower surface: Close to 142C; marginal edges, close to 70A to 70B.
  - Peduncles.—Length: About 4 cm to 6 cm. Diameter: About 3 mm by 5 mm. Strength: Moderately strong to strong. Aspect: About 15° to 20° from plant axis. Texture and luster: Smooth, glabrous; somewhat glossy. Color: Close to 63B speckled with close to 142D.
  - Reproductive organs.—Stamens: Quantity per flower: About 50 to 60. Filament length: About 1.5 cm to 2 cm. Filament color: Close to 9D. Anther shape: Oblong and retuse; basifixed. Anther size: About 1 mm by 2 mm. Anther color: Close to 6B. Pollen amount: Scarce. Pollen color: Close to 1C. Pistils: Quantity per flower: About four to seven. Pistil length: About 1.5 cm to 2 cm. Stigma shape: Tapered, pointed. Stigma color: Close to 145C. Style length: About 1 cm to 1.2 cm. Style color: Close to 145C. Ovary color: Close to 145B.
  - Nectaries.—Quantity per flower: About eight to ten. Length: About 7 mm to 9 mm. Width: About 1 mm to 2 mm. Shape: Tubular with circular apex. Margin: Entire; slightly undulate. Texture and luster, inner and outer surfaces: Smooth, glaucous; matte to slightly glossy. Color: When opening and fully opened, inner surface: Close to 145A and towards the apex, close to 145B; with subsequent development, color becoming closer to 142B with marginal edges, close to 71A and lightly speckled with close to 202A. When opening and fully opened, outer surface: Close to 145A and towards the apex, close to 145B; with subsequent development, color becoming closer to 142D with marginal edges, apex and stripes, close to N77B.
  - Seeds and fruits.—To date, seed and fruit development have not been observed on plants of the new Helleborus.
Garden performance: Plants of the new Helleborus have been observed to have good garden performance and to tolerate rain, wind and temperatures ranging from about −15° C. to about 34° 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

It is claimed:

1. A new and distinct Helleborus plant named ‘Borusmura25’ as herein illustrated and described.