Helleborus plant named ‘HGC Silvermoon’

Abstract

A new and distinct cultivar of Helleborus plant named ‘HGC Silvermoon’, characterized by its compact and mounded plant habit; dark green-colored leaves; and white to light green-colored flowers.

Description

Botanical classification/cultivar designation: Helleborus niger×H. sternii cultivar HGC Silvermoon.

BACKGROUND OF THE INVENTION

The present Invention relates to a new and distinct cultivar of Helleborus plant, botanically known as Helleborus niger×H. sternii, and hereinafter referred to by the cultivar name HGC Silvermoon.

The new Helleborus is a product of a planned breeding program conducted by the Inventor in Glandorf, Germany. The objective of the breeding program was to create new Helleborus cultivars with a good plant habit, that flower for a long period of time, and have attractive flower coloration.

The new Helleborus originated from a cross-pollination made by the Inventor in January, 1999 in Glandorf, Germany of an unnamed seedling of Helleborus niger, not patented, as the female, or seed, parent with an unnamed seedling of Helleborus sternii, not patented, as the male, or pollen, parent. The new Helleborus was discovered and selected by the Inventor as a flowering plant within the progeny of the stated cross-pollination in a controlled environment in Glandorf, Germany.

Asexual reproduction of the new cultivar by divisions at Glandorf, Germany since March, 2001, has shown that the unique features of this new Helleborus are stable and reproduced true to type in successive generations.

SUMMARY OF THE INVENTION

Plants of the cultivar HGC Silvermoon have not been observed under all possible environmental conditions. The phenotype may vary somewhat with variations in environment such as temperature and light level without, however, any variance in genotype.

The following traits have been repeatedly observed and are determined to be the unique characteristics of ‘HGC Silvermoon’. These characteristics in combination distinguish ‘HGC Silvermoon’ as a new and distinct cultivar of Helleborus:

• • 1. Compact and mounded plant habit.
  • 2. Dark green-colored leaves.
  • 3. White to light green-colored flowers.

Plants of the new Helleborus flower about two months later than plants of the female parent. In addition, plants of the new Helleborus and female parent differ in flower coloration. Compared to plants of the male parent, plants of the new Helleborus have less leaf serration and flower about one month earlier.

Plants of the new Helleborus can be compared to the Helleborus niger cultivar HGC Jericho, disclosed in U.S. Plant patent application Ser. No. 10/878,420. In side-by-side comparisons conducted in Glandorf, Germany, plants of the new Helleborus differed from plants of the cultivar HGC Jericho in the following characteristics:

• • 1. Plants of the new Helleborus had longer leaf petioles than plants of the cultivar HGC Jericho.
  • 2. Plants of the new Helleborus had flatter flowers than plants of the cultivar HGC Jericho.
  • 3. Plants of the new Helleborus and the cultivar HGC Jericho differed in flower coloration.

BRIEF DESCRIPTION OF THE PHOTOGRAPHS

The accompanying colored photographs illustrate the overall appearance of the new cultivar, 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 actual colors of the new Helleborus.

The photograph at the top of the sheet comprises a side perspective view of a typical flowering plant of ‘HGC Silvermoon’.

The photograph at the bottom of the sheet is a close-up view of a typical flower of ‘HGC Silvermoon’.

DETAILED BOTANICAL DESCRIPTION

The aforementioned photographs, following observations and measurements describe plants grown in Glandorf, Germany, in a glass-covered greenhouse and under commercial production practices during the winter. Plants were grown in 15-cm containers and were about six months old when the photographs and description were taken. During the production of the plants, day temperatures were about 18° C. and night temperatures were about 14° C. In the following description, color references are made to The Royal Horticultural Society Colour Chart, 1995 Edition, except where general terms of ordinary dictionary significance are used.

• Botanical classification: Helleborus niger×H. sternii cultivar HGC Silvermoon.
• Parentage:
  • • Female parent.—Unnamed seedling of Helleborus niger, not patented.
    • Male parent.—Unnamed seedling of Helleborus sternii, not patented.
• Propagation:
  • • Type.—By divisions.
    • Time to initiate roots, winter.—About 40 days at 12° C.
    • Time to produce a rooted plant, winter.—About six months at 12 to 15° C.
    • Root description.—About 3 to 15 thick fleshy roots; not branching; white to brown in color.
• Plant description:
  • • Plant form/habit.—Compact and mounded plant habit; moderately vigorous growth habit. Leaves basal. Single flower form.
    • Plant height.—About 14 cm.
    • Plant width (spread).—About 30 cm.
    • Foliage description.—Arrangement: Basal; palmately compound with three to five leaflets per leaf. Leaflet length: About 5 to 10 cm. Leaflet width: About 2.5 to 4 cm. Leaflet shape: Lanceolate; pedate. Leaflet apex: Apiculate. Leaflet base: Acute. Leaflet margin: Serrate. Texture, upper and lower surfaces: Smooth, glabrous. Venation pattern: Reticulate. Color: Developing leaflets, upper surface: 137A. Developing leaflets, lower surface: 147B. Fully expanded leaflets, upper surface: 147A. Fully expanded leaflets, lower surface: 147B. Venation, upper surface: 146B. Venation, lower surface: 183A. Petiole: Length: About 8 cm. Diameter: About 4 mm. Texture, upper and lower surfaces: Smooth, glabrous. Color, upper and lower surfaces: 183A.
• Flower description:
  • • Flower type/habit.—Single rounded flowers arranged singly on upright peduncles; flowers face upright to outwardly; petals inconspicuous. Freely flowering habit with about 10 flowers developing per plant over the flowering period.
    • Fragrance.—Slightly fragrant.
    • Natural flowering season.—Intermittent flowering from December to February in Glandorf, Germany. Flowers persistent.
    • Postproduction longevity.—Flowers last about ten days on the plant.
    • Flower buds.—Height: About 1.2 cm. Diameter: About 7 mm. Shape: Ovoid. Color: 145D.
    • Flowers.—Diameter: About 7 cm. Depth: About 1.5 cm.
    • Petals.—Size: Minute, obscured by reproductive organs; forming inconspicuous nectaries.
    • Sepals.—Quantity/arrangement per flower: Typically five in a single whorl. Length: About 3.5 cm. Width: About 3 cm. Shape: Broadly ovate. Apex: Rounded. Margin: Entire. Texture, upper and lower surfaces: Smooth, glabrous; satiny. Color: Developing sepals, upper surface: 155A. Developing sepals, lower surface: 155A slightly overlain with 60A. Fully expanded sepals, upper surface: 149D. Color becoming closer to 145B to 145C with development. Fully expanded sepals, lower surface: 149D slightly overlain with 187A.
    • Peduncles.—Length: About 5 to 7 cm. Diameter: About 3 to 5 mm. Orientation: Upright. Strength: Strong. Texture: Smooth, glabrous. Color: 145A overlain with 185A. Pedicels: None.
    • Reproductive organs.—Stamens: Quantity per flower: About 70. Anther shape: Oblong. Anther length: About 3 mm. Anther color: 154C. Pollen amount: None observed. Pistils: Quantity per flower: About five. Pistil length: About 2 cm. Stigma shape: Tuberculate. Stigma color: 145C. Style length: About 1.1 cm. Style color: 145C. Ovary color: 145B.
    • Seed/fruit.—Seed and fruit development have not been observed.
• Disease/pest resistance: Plants of the new Helleborus have not been noted to be resistant to pathogens and pests common to Helleborus.
• Temperature tolerance: Plants of the new Helleborus have been observed to tolerate temperatures from −10 to 36° C.

Claims

1. A new and distinct cultivar of Helleborus plant named ‘HGC Silvermoon’, as illustrated and described.