plant named ‘H223902’

Abstract

A new and distinct cultivar of Hydrangea plant named ‘H223902’, characterized by its relatively compact, upright and uniformly mounded plant habit; vigorous growth habit and rapid growth rate; freely branching habit with strong, thick and sturdy stems; freely and uniformly flowering habit; lacecap-type inflorescences with numerous double sterile flowers that are white in color; and good postproduction longevity.

Description

Botanical designation: Hydrangea macrophylla.

Cultivar denomination: ‘H223902’.

CLOSELY-RELATED APPLICATION(S)

An European Community Plant Breeder's Rights application for the instant plant was filed by the Applicant/Assignee, Hydrangea Breeders Association B.V. of De Kwakel, The Netherlands on Mar. 9, 2023, application number 2023/0587. Foreign priority is not claimed to this application.

BACKGROUND OF THE INVENTION

The present invention relates to a new and distinct cultivar of Hydrangea plant, botanically known as Hydrangea macrophylla, commercially referred to as a lacecap-type Hydrangea and hereinafter referred to by the name ‘H223902’.

The new Hydrangea plant is a product of a planned breeding program conducted by the Inventor in De Kwakel, The Netherlands and Lengerich, Germany. The objective of the breeding program was to create new strong and freely-branching Hydrangea plants with strong sturdy stems, uniform flowering habit, large inflorescences with numerous showy sterile flowers, attractive sterile flower color and good postproduction longevity.

The new Hydrangea plant originated from a cross-pollination made by the Inventor during the spring of 2016 in De Kwakel, The Netherlands, of a proprietary selection of Hydrangea macrophylla identified as code number 211322-001, not patented, as the female, or seed, parent with a proprietary selection of Hydrangea macrophylla identified as code number 212286-013, not patented, as the male, or pollen, patent. The new Hydrangea plant was discovered and selected by the Inventor as a single flowering plant from within the progeny of the stated cross-pollination in a controlled greenhouse environment in Lengerich, Germany during the spring of 2018.

Asexual reproduction of the new Hydrangea plant by vegetative tip cuttings in a controlled environment in De Kwakel, The Netherlands since the summer of 2018 has shown that the unique features of this new Hydrangea plant are stable and reproduced true to type in successive generations.

SUMMARY OF THE INVENTION

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

The following traits have been repeatedly observed and are determined to be the unique characteristics of ‘H223902’. These characteristics in combination distinguish ‘H223902’ as a new and distinct Hydrangea plant:

• • 1. Relatively compact, upright and uniformly mounded plant habit.
  • 2. Vigorous growth habit and rapid growth rate.
  • 3. Freely branching habit with strong, thick and sturdy stems.
  • 4. Freely and uniformly flowering habit.
  • 5. Lacecap-type inflorescences with numerous double sterile flowers that are white in color.
  • 6. Good postproduction longevity.

Plants of the new Hydrangea can be compared to plants of the parent selections. Plants of the new Hydrangea differ primarily from plants of the parent selections in sterile flower form as plants of the new Hydrangea have double-type sterile flowers whereas plants of the parent selections have single-type sterile flowers.

Plants of the new Hydrangea can be compared to plants of the Hydrangea macrophylla ‘H220909’, disclosed in U.S. Plant Pat. No. 33,739. In side-by-side comparisons, plants of the new Hydrangea differ primarily from plants of ‘H220909’ in the following characteristics:

• • 1. Plants of the new Hydrangea are more compact than plants of ‘H220909’.
  • 2. Plants of the new Hydrangea are more freely branching than plants of ‘H220909’.
  • 3. Plants of the new Hydrangea flower earlier than plants of ‘H220909’.
  • 4. Inflorescences of plants of the new Hydrangea have more sterile flowers than inflorescences of plants of ‘H220909’.

BRIEF DESCRIPTION OF THE PHOTOGRAPHS

The accompanying colored photographs illustrate the unique appearance of the new Hydrangea 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 from the color values cited in the detailed botanical description which accurately describe the colors of the new Hydrangea plant.

The photograph on the first sheet (FIG. 1) is a top perspective view of a typical flowering plant of ‘H223902’.

The photograph on the second sheet (FIG. 2) is a close-up view of a typical inflorescence of ‘H223902’.

DETAILED BOTANICAL DESCRIPTION

Plants used in the aforementioned photographs and in the following description were grown during the summer in 17-cm containers in a glass-covered greenhouse in Glandorf, Germany and under cultural practices typical of commercial Hydrangea production. During the production of the plants, day and night temperatures averaged 17 C. Plants of the new Hydrangea were 14 months old when the photographs and description were taken. Plants of the new Hydrangea are typically not treated with aluminum sulfate to “blue” the inflorescences. 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 description: Hydrangea macrophylla ‘H223902’.
• Parentage:
  • • Female, or seed, parent.—Proprietary selection of Hydrangea macrophylla identified as code number 211322-001, not patented.
    • Male, or pollen, parent.—Proprietary selection of Hydrangea macrophylla identified as code number 212286-013, not patented.
• Propagation:
  • • Type cutting.—By vegetative tip cuttings.
    • Time to initiate roots, summer.—About two weeks at temperatures about 23 C.
    • Time to initiate roots, winter.—About 18 days at temperatures about 20 C.
    • Time to produce a rooted young plant, summer.—About four weeks at temperatures about 23 C.
    • Time to produce a rooted young plant, winter.—About five weeks at temperatures about 20 C.
    • Root description.—Thick; typically whitish 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.—Freely branching; dense.
• Plant description:
  • • Plant and growth habit.—Relatively compact, upright and uniformly mounded plant habit; strong and sturdy stems; rapid growth rate and vigorous growth habit.
    • Plant height.—About 27 cm to 30 cm.
    • Plant diameter or area of spread.—About 55 cm to 65 cm.
• Lateral branch description:
  • • Branching habit.—Freely branching habit; when pinched, about ten lateral branches develop per plant.
    • Length.—About 15 cm to 20 cm.
    • Diameter.—About 5 mm to 7 mm.
    • Internode length.—About 3 cm to 5 cm.
    • Texture.—Smooth, glabrous; fully developed, woody.
    • Aspect.—Upright to slightly outwardly.
    • Strength.—Strong, sturdy.
    • Color, when developing.—Close to 144A.
    • Color, fully developed.—Close to 177C.
• Leaf description:
  • • Arrangement.—Opposite, simple.
    • Length.—About 8 cm to 10 cm.
    • Width.—About 6 cm to 7 cm.
    • Shape.—Ovate.
    • Apex.—Acute.
    • Base.—Obtuse.
    • Margin.—Dentate to serrate.
    • Texture, upper surface.—Smooth, glabrous.
    • Texture, lower surface.—Rugose, glabrous.
    • Venation pattern.—Pinnate.
    • Color.—Developing and fully expanded leaves, upper surface: Close to 139A; venation, close to 146C. Developing and fully expanded leaves, lower surface: Close to 137B; venation, close to 146C.
    • Petioles.—Length: About 3 cm to 4 cm. Diameter: About 2 mm to 4 mm. Texture, upper and lower surfaces: Smooth, glabrous. Color, upper and lower surfaces: Close to 146C.
• Flower description:
  • • Flower type and habit.—Double showy sterile flowers arranged on lacecap-type terminal panicles; to date, fertile flower development has not been observed on plants of the new Hydrangea; panicles flattened globular in shape; star-shaped flowers face upright to slightly outward depending on their position in the inflorescence.
    • Fragrance.—None detected.
    • Time to flowering.—Plants begin flowering about eight weeks after cold treatment.
    • Flower longevity.—Sterile flowers last about four months on the plant, sterile flowers persistent.
    • Quantity of flowers.—Freely flowering habit; about 300 to 400 sterile flowers per panicle.
    • Panicle height.—About 6 cm to 8 cm.
    • Panicle diameter.—About 18 cm to 22 cm.
    • Sterile flower buds.—Length: About 5 mm. Diameter: About 5 mm. Shape: Rounded. Color: Close to 145C.
    • Sterile flower diameter.—About 5 cm.
    • Sterile flower depth (height).—About 2 cm.
    • Petals, sterile flowers.—To date, petal development has not been observed on sterile flowers of plants of the new Hydrangea.
    • Sepals, sterile flowers.—Quantity and arrangement: About 12 to 14 in about three whorls. Length, outer whorl: About 2.5 cm. Length, inner whorls: About 1.5 cm. Width, outer whorl: About 2.5 cm. Width, inner whorls: About 1 cm. Shape: Elliptic to deltoid. Apex: Obtuse. Base: Cuneate. Margin: Entire. Texture, upper and lower surfaces: Smooth, glabrous. Color: When opening, upper and lower surfaces: Close to 145D. Fully opened, upper surface: Close to NN155B; color does not change with subsequent development. Fully opened, lower surface: Close to NN155D; color does not change with subsequent development.
    • Pedicels, sterile flowers.—Length: About 2.5 cm to 3 cm. Diameter: About 2 mm to 3 mm. Strength: Strong. Aspect: About 45 degrees from vertical. Texture: Smooth, glabrous. Color: Close to NN155B.
    • Reproductive organs, sterile flowers.—Stamens: To date, stamen development has not been observed on plants of the new Hydrangea. Pistils: Pistil quantity per flower: About three. Pistil length: About 1 mm. Stigma shape: Conical. Stigma color: Close to 155A. Style length: About 1 mm. Style color: Close to 155A. Ovary color: Close to 155A.
    • Seeds.—To date, seed development has not been observed on plants of the new Hydrangea.
• Pathogen & pest resistance: To date, plants of the new Hydrangea grown under commercial production conditions have not been observed to be resistant to pathogens and pests common to Hydrangea plants.
• Garden performance: Plants of the new Hydrangea have been shown to have good garden performance and to be tolerant to temperatures ranging from about 3 C to about 38 C.

Claims

1. A new and distinct Hydrangea plant named ‘H223902’ as illustrated and described.