Originally known as Hydrangea m. 'Horwack', then, thankfully, renamed 'Pistachio', this cultivar is a compact mophead that blooms on old wood, then later will repeat bloom on new wood from summer into fall. The plant is a compact grower to 3 ft tall and 4-5 ft wide. The sterile florets are a combination of chartreuse, scarlet red, and even violet red, giving the plant an unusual and flashy 'party' appearance. Valuable because of the interesting colors re-blooming over the summer. Glossy green leaves add to its attractive qualities.