#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. Plants used in the aforementioned photograph and in the following description were grown in Glandorf, Germany, in 15-cm containers in a glass-covered greenhouse and under conditions which closely approximate commercial production conditions. During the production of the plants, day and night temperatures were about 17° C. Plants of the new hydrangea were grown in a soilless media with a pH level of about 5.5. Plants were about one year old when the photograph and description were taken. The photograph and description were taken during the late winter/early spring. Botanical classification: Hydrangea hybrida cultivar 1701. Parentage: Male, or pollen, parent.—Proprietary Hydrangea hybrida selection identified as code number 98122-05, not patented. Female, or seed, parent.—Proprietary Hydrangea hybrida selection identified as code number 98002, not patented. Propagation: Type cutting.—By vegetative cuttings. Time to initiate roots, summer.—About 14 days at 23° C. Time to initiate roots, winter.—About 18 days at 18° C. Time to produce a rooted cutting or liner, summer.—About four weeks at 23° C. Time to produce a rooted cutting or liner, winter.—About five weeks at 18° C. Root description.—Thick; white to brown in color. Rooting habit.—Freely branching; dense. Plant description; Form/growth habit.—Upright and mounded plant habit. Strong lateral branches; vigorous growth habit. Plant height, soil level to top of plant plane.—About 30 to 40 cm. Plant diameter or area of spread.—About 50 cm. Branching habit.—When pinched, freely branching with about seven lateral branches per plant. Lateral branches.—Length: About 25 to 35 cm. Diameter: About 6 mm. Internode length: About 2.5 cm. Texture: Smooth, glabrous. Strength: Strong. Color: Close to 146A. Foliage description.—Leaves large, simple, opposite and durable. Length: About 11 cm. Width: About 7 cm. Shape: Elliptic to obovate. Apex: Acute. Base: Obtuse. Margin: Dentate. Texture, upper and lower surfaces: Smooth to rugose; glabrous. Venation pattern: Pinnate. Color: Developing and fully expanded foliage, upper surface: Close to 147A. Developing and fully expanded foliage, lower surface: Close to 147B. Venation, upper and lower surfaces: Close to 146A. Petiole: Length: About 3 cm. Diameter: About 4 mm. Texture, upper and lower surfaces: Smooth, glabrous. Color, upper and lower surfaces: Close to 146A. Flower description: Flower type and habit.—Single flat flowers arranged on terminal panicles; panicles large and globular. Flowers face upright to outward. Flowers persistent. Flowers not fragrant. Natural flowering season.—Intermittent flowering during the summer in Northern Europe. Flower longevity.—Flowers last about three months on the plant. Quantity of flowers.—Freely flowering; about 100 to 120 fertile and sterile flowers per panicle. Panicle diameter.—About 19 cm. Panicle height.—About 10 cm. Flower diameter.—About 4.5 cm. Flower depth (height).—About 5 mm. Flower buds.—Length: About 5 mm. Diameter: About 3 mm. Shape: Ovoid. Color: 145B to 145C. Petals.—Arrangement: Five in a single whorl. Length: About 4 mm. Width: About 2 mm. Shape: Ovate. Apex: Acute. Base: Attentuate. Margin: Entire. Texture, upper and lower surfaces: Smooth, glabrous. Color: When opening, upper and lower surfaces: 145D. Fully opened, upper surface: 75B; color becoming closer to 75A with development. Fully opened, lower surface: 75A. Sepals.—Quantity per flower: Four, fused into a calyx. Length: About 1.5 cm. Width: About 1.5 cm. Shape: Deltoid. Apex: Retuse. Base: Cuneate to attenuate. Margin: Entire; undulate. Texture, upper and lower surfaces: Smooth, glabrous. Color: When opening, upper and lower surfaces: 154D. Fully opened, upper surface: 73B to 73C. Fully opened, lower surface: 73C. Pedicels.—Angle: Erect to about 45° from vertical. Strength: Strong. Length: About 1 to 4 cm. Diameter: About 2 to 7 mm. Color: 57D. Reproductive organs.—Stamens: Quantity per flower: About three. Anther shape: Conical. Anther length: About 1 mm. Anther color: 156B. Pollen amount: Abundant. Pollen color: Close to 155D. Pistils: Pistil quantity per flower: About eight. Pistil length: About 3 to 4 mm. Stigma shape: Oval. Stigma color: 77B. Style length: About 2 to 3 mm. Style color: 69C. Ovary color: 69C. Seed: Length: About 1 mm. Diameter: About 0.2 mm. Color: Brownish Disease/pest resistance: Under commercial production conditions, plants of the new Hydrangea have not been observed to be resistant to pathogens or pests common to Hydrangea. Temperature tolerance: Plants of the new Hydrangea have been shown to be tolerant to temperatures ranging from about 3 to about 38° C.