Hydrangea macrophylla ‘Nikko Blue’, commonly known as Blue Hydrangea, is a classic mophead hydrangea cherished for its large, sky-blue flower clusters that bloom in early to mid-summer. This deciduous shrub reaches 4 to 6 feet tall and wide, with a rounded, bushy habit and lush green foliage. The vivid blue color appears in acidic soils, while flowers may turn lavender or pink in neutral to alkaline conditions. ‘Nikko Blue’ blooms on old wood, so protection from harsh winter weather and minimal pruning are key for consistent flowering year to year.

Why choose Nikko Blue Hydrangea

Iconic blue blooms: Produces bold, rounded clusters of flowers in acidic soils

Lush structure: Dense foliage and full form bring beauty even when not in bloom

Classic favorite: A long-standing garden staple for timeless summer color

Cultivating tips

Sun exposure: Prefers part shade—morning sun with afternoon shade is ideal

Soil needs: Moist, well-drained soil with organic matter; acidic soil keeps blooms blue

Maintenance: Low—prune only after flowering to preserve next year’s buds

Designs for your garden

Shaded borders: Adds bold color beneath trees or near walls

Foundation plantings: Softens building lines with rounded form and bloom

Cottage gardens: A perfect companion to ferns, astilbes, and native perennials

Ecological benefits

Pollinator attraction: Fertile blooms support bees and other insects

Seasonal interest: Colorful flowers and textured foliage enhance summer gardens

Low deer impact: Typically not preferred by browsing wildlife

Similar native alternatives

Looking for a native option? Here are three native plants that offer similar seasonal interest and landscape value:

• Hydrangea quercifolia Sykes Dwarf – Oakleaf Hydrangea
• Hydrangea quercifolia Snow Queen – Oakleaf Hydrangea
• Hydrangea quercifolia – Oakleaf Hydrangea