Hydrangea plant named 'hp221904'

Abstract

A new and distinct cultivar of Hydrangea plant named ‘HP221904’, characterized by its relatively compact, upright to somewhat outwardly spreading and rounded to conical plant habit; vigorous growth habit and rapid growth rate; freely branching habit with strong, thick and sturdy stems; freely and uniformly flowering habit; large rounded conical inflorescences with numerous light yellow green-colored sterile flowers that become purplish red in the autumn; and good garden performance.

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