Floribunda rose plant named ‘GRAaus’

Abstract

‘GRAaus’ is a new and distinct floribunda type Rosa hybrid cultivar which is characterized by the combination of an upright to semi-weeping growth habit, excellent resistance to Diplocarpon rosae, nearly continuous flowering, white double-type flowers with tinges of pale pink as flowers age, a moderate rose fragrance, 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 ‘GRAaus’, 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 15 month old ‘GRAaus’ plant 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 foliage and flower of ‘GRAaus’.

DETAILED BOTANICAL DESCRIPTION

(3) The following observations and measurements, made in February of 2016, describe averages of two own-root specimens of one year old ‘GRAaus’ plants. The plants were grown outdoors in 20 cm containers, in a soilless pine bark based growing media, 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 three times during the growing season using accepted techniques for rose pruning.

(4) Those skilled in the art will appreciate that certain characteristics will vary with older or, conversely, with younger plants. ‘GRAaus’ 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 ‘GRAaus’ and comparisons with the parents and the most similar commercial cultivar of Rosa hybrid are provided below. General plant description: Growth habit.—Upright to semi-weeping. Growth rate.—Approximately 1 year to reach 40 cm. Dimensions.—40 cm tall and 40 cm wide. Environmental tolerance.—Very good heat tolerance; cold hardiness is unknown. Disease resistance.—Excellent resistance to powdery mildew (Sphaerotheca pannosa) and blackspot (Diplocarpon rosae). 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 30 cm long; 0.6 cm in diameter near the base and tapering to 0.3 cm. Immature branches.—Diameter — Approximately 0.3 cm. Texture and pubescence — Smooth; glabrous to moderately pubescent. Color — Near RHS 136D. Prickles — Density — Moderate. Color — Near RHS 177A. Shape — Concave. Texture — Smooth. Mature branches.—Diameter — Approximately 0.7 cm, after one year. Texture and pubescence — Smooth and glabrous. Color — Near RHS 135D. Prickles — Density — Moderate. Color — Near RHS 177A. Shape — Concave. Texture — Smooth. Leaves: Arrangement.—Alternate imparipinnate compound leaves. Quantity.—Approximately 7 per mature branch. Attachment.—Petiolate. Leaf internode length.—1.7 cm. Dimensions.—Approximately 6 to 6.5 cm long and 5 cm wide. Petiole.—Dimensions — Average of 0.5 to 1.0 cm long and 0.1 to 0.2 cm wide. Color — RHS 142C. Texture and pubescence — Smooth and glabrous. Prickles — Not present. Stipitate glands — Not present. Stipule.—Dimensions — 0.7 cm long and 0.2 cm wide. Color — near RHS 144A. 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 — Near RHS 144A. Prickles — Not present. Stipitate glands — Not present. Leaflets.—Quantity — Normally 5 leaflets on axillary leaves. Dimensions — Average size of the terminal leaflet is 3.5 cm long and 2.5 cm wide. Shape — Ovate. Apex — Acuminate. Base — Ovate. Margins — Serrated. Texture, pubescence and luster, adaxial surface — Smooth, glabrous, and semi-glossy. Texture, pubescence and luster, abaxial surface — Smooth, glabrous, and matte. Juvenile foliage color, adaxial surface — Near RHS 142B, with some anthocyanin intonations, RHS 53A, at the margins and midrib. Juvenile foliage color, abaxial surface — Near RHS 145C, with some anthocyanin intonations, RHS 53A. Mature foliage color, adaxial surface — Near RHS N138B. Mature foliage color, abaxial surface — Near RHS 138D. Venation — Pinnate. Venation color, adaxial surface — Near RHS N138B. Venation color, abaxial surface — Near RHS 138D. Petiolule — Dimensions — 0.2 cm long and 0.1 cm wide. Color — Near RHS 144A. Prickles — Not present. Texture — Smooth. Inflorescence: Inflorescence type.—Terminal corymb consisting of approximately 2 to 4 pedicellate flowers. 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. Dimensions.—10 cm from the base of the lowest pedicel to the farthest distal flower and the width from farthest outstretched flower on one side of the inflorescence to the farthest outstretched flower on the opposite side is 15 cm. Peduncle.—Dimensions — 3.5 cm long and 0.2 cm in diameter. Color — Near RHS 144B. Strength — Strong. Texture and pubescence — Smooth and glabrous. Prickles — Not present. Bud: Shape.—Ovate. Size.—2 cm long and 1 cm in diameter. Color.—Near RHS 145B. Flower: Pedicel.—Dimensions — 3.5 cm long and 0.3 cm wide. Color — Near RHS 144B. Strength — Strong. Texture — Smooth. Calyx.—General — Comprised of five polysepalous sepals, with strong foliaceous appendages present on all sepals. Diameter of calyx — 0.5 cm. Sepals — Color, interior surface — RHS 145D. Color, exterior surface — RHS 145B. Dimensions — 2.0 cm long and 0.6 cm wide. Apex — Acuminate. Base — Flat at union with receptacle. Quantity — Five. Pubescence — Densely puberulent. Margins — Two to three strong foliaceous appendages. Stipitate glands — Not present. Corolla.—General shape of corolla — Cupped and well-rounded at anthesis; aging to a loose whorl. Rate of opening — 6 days from bud to anthesis. Dimensions — 6 cm in diameter and 3.5 cm deep. Upper profile — Cupped. Lower profile — Flat. Fragrance — Moderate rose scent. Lastingness — On the plant for 5 days after anthesis. Persistence — Self-cleaning. Petals — Petal count — Exhibits double flowers with approximately 32 petals under normal conditions. Petal arrangement — Tight whorl, loosening as the flower ages. Dimensions — 3.2 cm long and 2.2 cm wide. Petal shape — Obovate. Apex — Rounded to cordate. Base — Flattened, then obtuse. Petal reflex — Slightly reflexed at apex. Petal margin — Entire; slightly undulating. Texture — Soft. Aspect — Slightly ruffled. Petal color, upon opening — Upper surface — Near RHS NN155D. Lower surface — Near RHS NN155D. Petal color, at anthesis — Upper surface — Near RHS N155C. Lower surface — Near RHS N155C. Fading — White, RHS N155C, with intonations of pale pink, near RHS 27B. Reproductive organs: Stamens.—Quantity — Approximately 30. Anthers — Shape — Narrow ovate. Length — 0.1 cm. Color — Near RHS 21B. Pollen — Many. Pollen Color — Near RHS 3A. Filaments — Color — Near RHS 8C. Length — Approximately 0.7 cm. Pistils.—Quantity — Approximately 50. Length — Approximately 1.0 cm. Stigma — Shape — Ovate. Color — Near RHS 11B. Styles — Length — Approximately 0.8 cm long. Color — Near RHS 18C. Ovary.—Dimensions — 0.5 cm long and 0.3 cm wide. Color — Near RHS 3D. Receptacle.—Shape — Pitcher-shaped. Dimensions — 0.5 cm high and 0.5 cm wide. Color — RHS 144D. Hip and seed: Hip.—Shape — Rounded. Dimensions — 1 cm long and 1 cm wide. Texture — Smooth. Color — Near RHS 138C. Seed.—Shape — Rounded. Dimensions — 1 cm long and 1 cm wide. Color — Near RHS 134D.

COMPARISONS WITH THE PARENTS

(6) The new rose plant ‘GRAaus’ may be distinguished from its seed parent, an unnamed breeding line, by the following combination of characteristics: 1. The flowers of ‘GRAaus’ exhibit a distinct white general tonality, whereas the flowers of the seed parent exhibit a soft pink general tonality. 2. ‘GRAaus’ exhibits an upright to semi-weeping growth habit, whereas the seed parent exhibits an upright growth habit.

(7) The new rose plant ‘GRAaus’ may be distinguished from its pollen parent, an unnamed breeding line, by the following combination of characteristics: 1. The flowers of ‘GRAaus’ exhibit a distinct white general tonality, whereas the flowers of the pollen parent exhibit a purple general tonality. 2. ‘GRAaus’ exhibits an upright to semi-weeping growth habit, whereas the pollen parent exhibits an upright growth habit. 3. ‘GRAaus’ exhibits juvenile foliage colored near RHS 142B with anthocyanin intonations, whereas the pollen parent exhibits juvenile foliage colored near RHS 137C with no anthocyanin intonations.

COMPARISONS WITH THE MOST SIMILAR VARIETY OF COMMON KNOWLEDGE

(8) Plants of the new cultivar ‘GRAaus’ may be distinguished from the commercial variety Rosa hybrid ‘GRAppl’ (U.S. Plant Pat. No. 26,364) by the following combination of characteristics: 1. The flowers of ‘GRAaus’ exhibit a distinct white general tonality, whereas the flowers of ‘GRAppl’ exhibit a purple general tonality. 2. ‘GRAaus’ exhibits average leaf dimensions of 6 to 6.5 cm long and 5.0 cm wide, whereas ‘GRAppl’ exhibits average leaf dimensions of 13.5 cm long and 8.5 cm wide. 3. Mature field-grown ‘GRAaus’ plants exhibit an average plant height of 75 cm, whereas ‘GRAppl’ exhibits an average plant height of 120 cm. 4. ‘GRAaus’ exhibits a rotund plant shape with more twiggy stems, whereas ‘GRAppl’ exhibits an upright shape with strong main stems.