Botanical name: Hydrangea macrophylla ssp. serrata Family: Hydrangeaceae (Hydrangea family)
Synonyms: Hydrangea serrata var. acuminata, Hydrangea acuminata, Viburnum serratum
Mountain hydrangea is similar to big leaf hydrangea except it is a smaller more compact shrub with smaller flowers and leaves; it is also more hardy than bigleaf hydrangea. Mountain hydrangea is a deciduous shrub with a rounded habit that typically grows 2 to 4 feet tall. It features dark green, serrated (toothed), ovate leaves (to 6" long), and clusters of long-blooming summer flowers. Both showy sterile florets and less showy fertile florets appear in each cluster. It flowers from July to August, with blue or pink lacy flowerheads. The flowers are perfect, having both male and female parts; they are insect pollinated. Mountain Hydrangea is made up of a center of tiny dark blue fertile flowers, surrounded by large sterile petals of palest bluish-purple. It is bluer in acidic soil than alkaline, but it's fairly blue in any soil condition. As insects pollinate the fertile flowers of the center, they turn their petals to reveal pinker reverse side. Occasionally listed as a vine, it's hard to imagine this compact rounded shrub as a vine, but the main stems do often bend & twist. If it were trained to an espalier beginning when still small in size, it could be given to the appearance of a six foot tall climber. Growth rate is moderate to rapid.
Identification credit: R.K. Nimai Singh
The flower labeled Mountain Hydrangea is ...