Floribunda rose plant named ‘GRAalpha’

Abstract

GRAalpha is a new and distinct floribunda type Rosa hybrid plant which is characterized by the combination of an semi-weeping to spreading growth habit, very high resistance to Diplocarpon rosae and Podosphaera pannosa, nearly continuous flowering, distinct flower color dominated by yellow with irregular orange variegated areas that are splashed and flecked with yellow, and the stability of these characteristics from generation to generation. The new cultivar is generally suited to landscape applications.

Claims

1. A new and distinct variety of Rosa hybrid plant named GRAalpha, as described and illustrated herein.

Description

BRIEF DESCRIPTION OF THE DRAWING

(1) FIG. 1 illustrates, as nearly true as it is reasonably possible to make the same in color photographs of this type, an exemplary 12 month old GRAalpha plant, exhibiting several faded flowers, grown outdoors at the inventor's commercial nursery in Highfields, Australia.

(2) FIG. 2 illustrates, as nearly true as it is reasonably possible to make the same in color photographs of this type, the typical flower of GRAalpha.

DETAILED BOTANICAL DESCRIPTION

(3) The following observations and measurements, made in February of 2019, describe averages of two own-root specimens of one year old GRAalpha plants. The plants were grown outdoors in a garden bed of a red krasnozem soil in full sunlight, at the inventor's nursery in Highfields, Australia. No shade or supplemental light was provided. Temperatures ranged from approximately 17 to 35 degrees Celsius during the day and 7 to 18 degrees Celsius at night. Standard practices for irrigation, fertilizer and pest control were applied at appropriate times during the growing season. The plants were pruned.

(4) Those skilled in the art will appreciate that certain characteristics will vary with older or, conversely, with younger plants. GRAalpha has not been observed under all possible environmental conditions. Where dimensions, sizes, colors and other characteristics are given, it is to be understood that such characteristics are approximations or averages set forth as accurately as practicable. The phenotype of the variety may differ from the descriptions set forth herein with variations in environmental, climatic and cultural conditions. Color notations are based on The Royal Horticultural Society Colour Chart, The Royal Horticultural Society, London, 2007 Fifth Edition except where common terms of color are used.

(5) A botanical description of GRAalpha and comparisons with the parents and the most similar commercial cultivar of Rosa hybrid are provided below. General plant description: Growth habit.Semi weeping to spreading. Growth rate.Approximately 10 months to reach 60 cm. Dimensions.80 cm tall and 80 cm wide. Environmental tolerance.Very good heat tolerance; cold hardiness is unknown. Disease resistance.Very high resistance to powdery mildew (Sphaerotheca pannosa) and very high resistance to blackspot (Diplocarpon rosae). Pest resistance.Neither resistance nor susceptibility to typical Rosa sp. pests has been observed. Propagation.Technique Softwood stem cuttings. Time to initiate roots About 13 days at approximately 21 degrees Celsius at root zone and 18 degrees Celsius ambient temperature. Time to produce a rooted cutting About 25 days at approximately 21 degrees Celsius at root zone and 18 degrees Celsius ambient temperature. Root system: White fibrous roots with many root hairs extending from lesser roots in a featherlike arrangement. Branches: Branching habit.Irregular branching from mature branches, breaking first from the uppermost buds near the apex of each shoot. Quantity.Numerous. General dimensions.Approximately 60 cm long; 1.5 cm in diameter near the base and tapering to 0.5 cm. Immature branches.Length 27 cm. Diameter Approximately 0.4 cm. Texture and pubescence Glabrous, with prickles. Color Nearest to RHS 144C. Prickles Density Moderate; 4 prickles per 2.5 cm of branch. Color Nearest to RHS 152D. Shape Convex. Texture Smooth. Length 0.7 cm. Mature branches.Length 60 cm. Diameter Approximately 0.5 cm, after one year. Texture and pubescence Glabrous, with prickles. Color Nearest to RHS 144C. Prickles Density Moderate. Color Nearest to RHS N167C. Shape Convex. Texture Smooth. Length 0.7 cm. Leaves: Arrangement.Alternate imparipinnate compound leaves. Quantity.Approximately 7 per mature branch. Attachment.Petiolate. Leaf internode length.2.5 cm. Dimensions.Approximately 10 cm long and 70 cm wide. Petiole.Dimensions 2.0 cm long and 0.1 to 0.2 cm wide. Color Nearest to RHS 150B and margined RHS 143C. Texture and pubescence Smooth and glabrous. Prickles Not present. Stipitate glands Not present. Stipule.Shape Linear to lanceolate. Dimensions 1.0 cm long and 0.5 cm wide. Color Nearest to RHS 150B. Texture and pubescence Smooth and glabrous. Margins Ciliate. Apex Apiculate. Base Winged. Prickles Not present. Stipitate glands Not present. Rachis.Dimensions 1.0 cm long and 0.1 cm wide. Color Nearest to RHS 145A. Prickles Present. Stipitate glands Not present. Leaflets.Quantity Seven leaflets on axillary leaves. Dimensions Average size of the terminal leaflet is 4.5 cm long and 3.0 cm wide. Shape Ovate. Apex Acuminate. Base Acute. Margins Serrated. Texture, pubescence and luster, adaxial surface Smooth, glabrous and glossy. Texture, pubescence and luster, abaxial surface Smooth, glabrous and matte. Juvenile foliage color, adaxial surface Near RHS N144C, with no anthocyanin intonations. Juvenile foliage color, abaxial surface Near RHS 145B, with no anthocyanin intonations. Mature foliage color, adaxial surface Nearest to RHS 143A. Mature foliage color, abaxial surface Nearest to RHS 145C. Venation Pinnate. Venation color, adaxial surface Nearest to RHS 143A, with midrib RHS 145C. Venation color, abaxial surface Nearest to RHS 145C, with midrib RHS 145C. Petiolule Dimensions 0.2 cm long and 0.1 cm wide. Color Nearest to RHS 144C with no anthocyanin intonations present. Prickles Not present. Texture Smooth. Inflorescence: Inflorescence type.Flowers are single or clustered. Blooming habit.Almost continuous from October through June in the southern hemisphere. Time to flower.6 to 8 weeks for a new stem to mature and flowering begins to occur once a stem matures. Peduncle.Dimensions 80 cm long and 0.3 cm in diameter. Color Nearest to RHS 145A. Strength Strong. Texture and pubescence Smooth and glabrous. Prickles None present. Bud: Shape.Ovate. Size.2.0 cm long and 1.5 cm in diameter. Color.Nearest to RHS 142B. Flower: Pedicels.Dimensions 3.0 cm long and 0.2 cm in diameter. Color Nearest to RHS 46B. Strength Moderately strong. Texture and pubescence Smooth and glabrous. Prickles None present. Calyx.General Comprised of five polysepalous sepals. Diameter of calyx 0.8 cm Sepals.Shape Lanceoalate; occasionally with leafy appendages. Color, interior surface RHS 152A. Color, exterior surface RHS 144C. Dimensions 2.5 cm long and 1.0 cm wide. Apex Apiculate. Base Flat at union with receptacle. Quantity Five. Pubescence Densely puberulent. Margins Entire. Stipitate glands None present. Corolla.General shape of corolla High centered and irregularly-rounded with a tight outer whorl; opening to nearly flat. Rate of opening 6 days from bud to anthesis. Dimensions Approximately 7 cm in diameter and 3 cm deep. Fragrance Light rose scent. Lastingness On the plant for 5 days after anthesis. Persistence Self-cleaning. Petals.Petal count Exhibits double flowers with approximately 35 petals under normal conditions. Petal arrangement Irregularly rounded whorl at anthesis and aging to a loose whorl. Dimensions 3.5 cm long and 4.0 cm wide. Petal shape Rounded. Apex Rounded. Base Flattened, then obtuse. Petal reflex Not reflexed at apex. Petal margin Entire; slightly undulating. Texture Hard. Aspect Formal. Petal color, upon opening Upper surface Nearest to RHS 6A, and striped and flecked with RHS N30D. Lower surface RHS 6B, and striped and flecked with RHS N30A. Petal color, at anthesis Upper surface Nearest to RHS 6A, and striped and flecked with RHS N30D. Lower surface RHS 6B, and striped and flecked with RHS N30A. Fading Nearest to RHS 45B. Reproductive organs: Stamens.Quantity Approximately 50. Anthers Shape Narrow ovate. Length 1.0 cm. Color Nearest to RHS 12A. Pollen Many. Pollen Color Nearest to RHS 3A. Filaments Color Nearest to RHS 17C. Length Approximately 0.8 cm. Pistils Quantity Approximately 50. Length Approximately 1.0 cm. Stigma.Position Held level at one-quarter the length of the filament and anther. Shape Ovate. Color Nearest to RHS 11B. Style.Length Approximately 0.8 cm long. Color Nearest to RHS 18C. Ovary.Dimensions 0.5 cm long and 0.3 cm wide. Color Nearest to RHS 3D. Receptacle.Shape Pitcher-shaped. Dimensions 0.5 cm high and 0.5 cm wide. Color Nearest to RHS 141D. Hip and seed: Not observed.

COMPARISONS WITH THE PARENTS

(6) The new rose plant GRAalpha may be distinguished from its seed parent, an unnamed breeding line, by the following combination of characteristics: 1. The flowers of GRAalpha exhibit a distinct flower color dominated by yellow with irregular orange variegated areas that are splashed and flecked with yellow, whereas the flowers of the seed parent exhibit a yellow general tonality. 2. GRAalpha exhibits a semi weeping to spreading growth habit, whereas the seed parent exhibits an upright growth habit.

(7) The new rose plant GRAalpha may be distinguished from its pollen parent, an unnamed breeding line, by the following combination of characteristics: 1. The flowers of GRAalpha exhibit a distinct flower color dominated by yellow with irregular orange variegated areas that are splashed and flecked with yellow, whereas the flowers of the pollen parent exhibit a yellow color with pink stripes and flecks. 2. GRAalpha exhibits a very high resistance to powdery mildew and blackspot, whereas the pollen parent is susceptible.

COMPARISONS WITH THE MOST SIMILAR VARIETY OF COMMON KNOWLEDGE

(8) Plants of the new cultivar GRAalpha may be distinguished from the commercial variety Rosa hybrid MACoranlem (not patented) by the following combination of characteristics: 1. MACoranlem is tall and arching, whereas GRAalpha is semi weeping to spreading in growth habit. 2. Immature branches of MACoranlem have anthocyanin present, whereas it is absent in GRAalpha. 3. GRAalpha has flowers with little fragrance, whereas MACoranlem flowers have mild fragrance.