Rainbow of Choices

Hydrangea arborescens

• Commonly known as smooth hydrangea or ‘Annabelle’ hydrangea after a particularly popular cultivar
• Blooms on new wood
• After landscape establishment, gardeners can cut this type back to about 1 ft. from the ground every winter/early spring.
• New branches will produce buds and bear flower heads all in the same season
• White, pink or green flowers, usually globe-shaped

Hydrangea macrophylla

• A species that originated in coastal regions of Japan; they do well in the Cape Cod maritime climate.
• Colors range from white to pink, blue or purple flowers, depending on the soil’s acidity. Blue flowers develop with acidic soil (a pH of 5.0 to 5.5) and pink flowers from alkaline soil pH (6.0 to 6.5). Aluminum sulfate can be added to acidify the soil, and lime to produce a more alkaline soil.
• Full sun to part shade
• Also known as florist’s, hortensia, mophead or lacecap
• Blooms on old wood
• Could benefit from winter protection, especially on spring evenings where frost threatens

Hydrangea paniculata

• Originated in the Asian mountains in high elevations
• Very cold hardy from Zones 3 to 8 and prefers full sun, especially in northern climates
• Most drought tolerant of the species
• Typically strong growers, 5 to 10 feet height and width in bush form; great specimen plants as standards (tree form)
• Very long-lived; some plants are 100 years old
• Flowers on new wood (buds form in the spring)
• Bloom color unaffected by soil pH
• Panicle blooms feature clusters of flowers on a branch and typically open white with maturing shades of lime green to pink to mauve from mid-summer to mid-fall.

Hydrangea petiolaris

• Commonly known as climbing hydrangea
• Formerly known by full botanical name: Hydrangea anomala subsp. petiolaris
• White disc-shaped flowers; stems need support of a tree or structure to climb
• Blooms on old wood
• Prefers part shade

Hydrangea quercifolia

• Commonly known as oakleaf hydrangea
• White conical flowers and large, oak-shaped leaves
• Depending on the variety, the oak-like leaves can grow up to 12 inches wide.
• The cone-shaped flower clusters combine large, showy florets with small, budlike flowers.
• Blooms on old wood
• Full sun/part shade
• Rarely needs winter protection
• Unlike mophead hydrangeas, soil pH doesn’t affect the color of oakleaf blooms.

Hydrangea serrata

• Commonly known as mountain hydrangea
• A hardy species of Asian mountain origin growing in the forest understory.
• Cold hardy from Zones 5 to 8, prefers shadier locations — at least a half-day of shade; prone to leaf spotting in high sun locations
• Hybridizes well with H. macrophylla; often utilized in newer rebloomers
• Upright bush of rounded habit, 2 to 6 feet height and width
• Mostly delicate lace cap flowers with only a few mophead choices; lace caps feature a set of smaller inner fertile blooms and larger colorful outer petals
• Blooms early in summer on old wood (buds form in the fall) with slightly subdued bloom color range: whites, pale greens, pinks, blues and some reds depending on soil pH and cultivar

Source: Heritage Museum and Gardens