Hydrangea macrophyllaHydrangea macrophylla

  • BOTANICAL NAME: Hydrangea macrophylla
  • PRONUNCIATION: hye-DRAN-ja-mack-roe-FIL-luh
  • COMMON NAME: Bigleaf Hydrangea
  • FAMILY: Hydrangeaceae
  • NATIVITY: Japan, China
  • GROWTH HABIT: Rounded dense deciduous shrub of erec, usually unbranched multi-stems; fast growing once established
  • SIZE: 3' to 8' height ( maintain at smaller heights or growing smaller cultivars) by 3' to 6' width
  • HARDINESS: Zone 4 - 7.
  • CULTURE: Well-drained, moist, loamy soil; full sun or full or part shade; Acid or basic soil (acidic results in blue flowers; neutral to basic results in pink flowers); prune after flowering since buds are formed on previous season's growth; prune 1/3 of wood on annual basis.
  • LANDSCAPE USE: Single use or massed; containers; foundation plant or in mixed border; accent; cut flowers; seaside
  • FOLIAGE: Opposite; simple; serrate margin; obovate shape; pinnate venation
  • BUDS:
  • BARK: Straw, tan color; large leaf scars
  • FLOWER: pH effect: Sterile, outer flowers are pink, bluish, purple, entire or toothed, up to 2" or more in diameter, the fertile flowers are usually blue or pink; both are borne in large, broad, flat-topped, much-branched, cymose corymbs; July through August.
  • FRUIT: Dry capsule, 1/2 to 5/16" long, not showy usually brown color
  • PROPAGATION: Cuttings; layering
  • PESTS: Aphids, leaf tiers, red spiders, rose chafers; leaf spot under nursery production; bacterial wilt
  • CULTIVARS:

    • 'Ayesha' - The unusual flower is bicolored; pale pink or mauve on the edge to white in the center of the cup shaped petals of this mophead inflorescence.

    • ‘Blaumeise’ - A stunning lacecap developed in Switzerland, ‘Blaumeise’ has large flat flowers composed of very wide deep purple blue sterile florets surrounding tiny indigo blue fertile flowers.

    • ‘Hororb’ AbracadabraTM Orb™ - A member of the Abracadabra™ hydrangea series. The sterile flowers of this mophead inflorescence emerge green and peach before maturing to hot pink (blue in acid). The mahogany–colored stems offer a dramatic contrast to the flower color.

    • ‘Lynn’ Let’s Dance® Starlight - A member of the Let’s Dance® series, with very compact, reblooming, lacecap hydrangea flowers on both new and old wood providing an extended season of vivid blue to pink color depending on soil pH.

    • ‘Madame Emile Mouillere’ - Considered by the late great gardener and writer Christoper Lloyd of Great Dixter to be the best pure white mophead. Tightly packed serrated flowers open wide and push against each other to produce a lacy work of art. Flowers age to blush pink or green and are great to cut and dry.

    • ‘SMHMP1’ Paraplu™ - The intense color of this dwarf mophead varies from bubblegum pink to intense hot pink, possibly with some purple in acidic soils.

    • 'Tokyo Delight' - An old lacecap favorite with outer white sterile flowers that slowly mature to burgundy around bright blue to mauve fertile flowers.

    • ‘Tovelit’ - The rose to mauve colored flowers and the uniquely serrated petals of the flowers gives this mophead abundant charm.

 

University of Delaware

University of Delaware Botanic GardensNewark, DE 19716Phone: 302 831-0153