Incrediball® Hydrangea | Giant White Blooms

The Biggest Hydrangea Blooms You Can Grow — On Stems That Don’t Droop

Incrediball® Hydrangea (Hydrangea arborescens 'Abetwo') solves the most frustrating problem with large-flowered hydrangeas: stem flop. Traditional smooth hydrangeas like 'Annabelle' produce enormous blooms but on weak stems that collapse under the weight of rain or the flowers themselves, leaving a sprawling mess. Incrediball® was specifically bred with dramatically stronger, thicker stems that hold those massive 12-inch flower heads upright through summer storms and heavy rain. The result is the most spectacular display of any smooth hydrangea — giant, globe-shaped white flowers that open in early summer, mature to a beautiful jade-green in late summer, and persist through fall. And unlike bigleaf hydrangeas, Incrediball® blooms reliably every year regardless of winter severity, making it one of the most dependable flowering shrubs available for cold climates.

Why Incrediball® Outperforms 'Annabelle'

• Dramatically stronger stems — the defining improvement over 'Annabelle'; thick, sturdy stems hold 12-inch blooms upright through rain and wind without staking
• Massive 12-inch flower heads — among the largest blooms of any hydrangea; globe-shaped white flowers that create an immediate, dramatic landscape impact
• Three-season color — brilliant white in early summer; matures to jade-green in late summer; persists as attractive dried flower heads through fall and winter
• Blooms on new wood — unlike bigleaf hydrangeas, Incrediball® blooms on new growth each year; late frosts and harsh winters never prevent blooming
• Exceptional cold hardiness — hardy to zone 3; one of the most cold-tolerant hydrangeas available; reliable in climates where bigleaf hydrangeas struggle
• Excellent cut and dried flower — massive blooms are stunning in fresh arrangements; dry beautifully for long-lasting dried arrangements
• Pollinator magnet — large flower heads attract butterflies and beneficial insects throughout the bloom season

Incrediball® vs. Endless Summer®

Both are excellent hydrangeas, but they are different species suited to different needs. Incrediball® (H. arborescens) is a smooth hydrangea — white blooms only, blooms on new wood every year regardless of winter, hardy to zone 3, and produces the largest individual flower heads. Endless Summer® (H. macrophylla) is a bigleaf hydrangea — blue or pink blooms (color changes with soil pH), reblooms on old and new wood, hardy to zone 4. Choose Incrediball® for maximum bloom size, cold hardiness, and reliability; choose Endless Summer® for color variety and the color-change experience.

Hardiness & Growing Zones

• USDA Hardiness Zones: 3–9
• Zones 3–5: Fully cold-hardy; may die back to the ground in severe winters but regrows vigorously from the roots and blooms on new wood each spring; one of the few hydrangeas that performs reliably in these zones
• Zones 6–7: Ideal conditions; vigorous growth with prolific blooming from early summer through fall
• Zones 8–9: Thrives with morning sun and afternoon shade; provide consistent moisture during summer heat; may bloom earlier (late spring) in the warmest locations
• Sunlight: Full sun to partial shade (morning sun with afternoon shade is ideal in zones 7+; tolerates more sun in cooler climates with consistent moisture)
• Soil: Moist, well-drained, rich in organic matter; consistent moisture is key to the largest blooms
• Mature size: 4–5 ft tall × 4–5 ft wide
• Bloom time: Early summer through fall (June–October in most zones)

Planting & Care Tips

Plant in moist, well-drained soil with good organic matter. Water deeply and consistently — adequate moisture is the key to producing the largest possible blooms. Mulch 2–3 inches around the base to retain moisture and keep roots cool. Fertilize once in early spring with a balanced slow-release fertilizer. Cut the entire plant back to 12–18 inches in late winter or early spring before new growth emerges — this is the single most important maintenance task, as it encourages the most vigorous new growth and the largest blooms. Do not prune in fall, as this is unnecessary and removes the attractive dried flower heads that provide winter interest.

Available Sizes

• 2 Gallon — well-rooted young plant; most economical
• 3 Gallon — larger specimen; faster to first full bloom display
• 5 Gallon — most established; may produce full-sized blooms in the first season after planting