June 28th, 2021
With their showstopping blooms and timeless shape, hydrangeas are an garden staple. Native to China, Korea, and Japan, hydrangea (hy-DRAIN-juh) are commonly available as cultivars of three species—the bigleaf hydrangea, Hydrangea macrophylla, the panicle hydrangea, Hydrangea paniculata, and the smooth hydrangea, Hydrangea arborescens.
Hydrangea macrophylla are part-shade loving, smaller hydrangeas that tote colorful ball-shaped flower clusters that vary widely in color, including varieties whose flower color changes with soil pH. These varieties, such as the Endless Summer ‘Twist-n-Shout,’ will have blue flowers with more acidic soils treated with soil acidifier, and pink flowers with more basic soils treated with garden lime. Other, non-transforming color varieties include the purple and pink flowers of Seaside Serenade ‘Newport’ and the pink flowers of Seaside Serenade ‘Hamptons’. These hydrangea flower on new and old growth, meaning pruning can be done at any time after the shrub has leafed out, but is not necessary.
Hydrangea paniculata are part to full sun loving, larger hydrangeas that have conical panicles of flowers on new growth. Many iconic varieties of panicle hydrangea exist, including the beautiful white flowers of ‘Bobo,’ green flowers of ‘Limelight’ and the mini shrub ‘Little Lime,’ and the striking pink flowers of ‘Quick Fire’ and the mini shrub ‘Little Quick Fire.’ These hydrangeas should be pruned in the spring, before leafing out, by about 30-50% on each stem for best growth.
Hydrangea arborescens are part to full shade loving, moderately sized hydrangeas with large, spherical flowers which bloom only on new growth. These hydrangeas should be pruned back to one to two feet above ground in late winter or early spring to encourage more vigorous growth. Iconic smooth hydrangea varieties include the stunning white flowers of the classic ‘Anabelle’ and the more upright ‘Incrediball,’ the green flowers of ‘Seaside Serenade Bar Harbor,’ and the mauve flowers of ‘Invincibelle Mini Mauvette.’