Enchanting in any garden, these old-fashioned flowering shrubs tend to live long and prosper in the South.
Written by Leslie Criss
When many of us imagine hydrangeas, what comes to mind are the most common type with large, cloud-like tufts of pastel pink, blue and lavender blossoms. With their old-fashioned feel, hydrangeas often grew tall, thick and prolifically around the houses of our grandparents. In addition to being just plain pretty, hydrangeas took on a magical quality when we were told if we stuck a nail in the ground near the plant’s roots and waited patiently, eventually the flowers would change colors.
Turns out there’s much more to them than those most common — and very popular — mophead hydrangeas. And the color change has everything to do with science and the pH of the soil, and not much to do with magic.
Betsy Moore has been a Tupelo Master Gardener for nearly 15 years, and her knowledge of hydrangeas is often shared with the botanically challenged. The truth is this: There is a whole lot of information out there regarding hydrangeas.
The word hydrangea comes from two Greek words, hydro (water) and angeion (vessel), perhaps for the plant’s thirsty habits or because the plant’s seed capsules are shaped like Grecian water jars. Most hydrangeas are native to China, Japan and Korea, though some species originated in the United States.
“They’ve been a familiar part of the Southern landscape since they were imported from Japan in the 1750s,” Moore said.
There are more than 70 species of hydrangeas, and like many flowers and plants, there’s a name for each type, like Ayesha, Blushing Bride, Dooley, Nikko Blue, Penny Mac, Lady in Red, just to name a few. The publication “Hydrangeas for Mississippi Gardens” by the Mississippi State University Extension, lists the most commercially available:
Bigleaf or French Hydrangea: There are two categories into which these fall, depending on the shape of the flower head. The most common is the mophead, with its large pom-pom shaped flower. The other category is the lacecap. Bigleafs grow fast and can be 3 to 6 feet tall and about that same width.
Panicle Hydrangea: These grow to 10- to 15-foot shrubs or 25-foot trees. Flowers grow in 10- to 15-inch clusters, first white, then pink. Blooms are cone-shaped and enjoy full sun.
Oakleaf Hydrangea: This shrub-like plant grows 6 to 10 feet tall with oak-like leaves that are a red-bronze hue in the fall. White cone-shaped flowers become pinkish with age. Tolerates sun but needs some shade.
Mountain or Sawtooth Hydrangea: This has smaller leaves and flowers but is much like bigleaf hydrangea. Grows 3 to 5 feet tall with dark green leaves, and flowers may be lacecaps or mopheads.
Smooth Hydrangea: Native to Mississippi, these shrubs are 5 to 6 feet, have weak twigs and thin leaves. Flowers are small and greenish white, and they bloom from May to June.
Climbing Hydrangea: This plant is a vine that climbs, has round-like leaves and white, lacecap flowers.
“For the most part, hydrangeas are easy to cultivate, tolerate almost any soil and produce abundant blooms,” Moore said. “Once hydrangeas have been established for a few years, they are very hardy plants.”
She recommends a soil test before planting hydrangeas, and also to help existing hydrangeas.
Old-fashioned or mophead hydrangeas are easy to grow: They need partial shade and a moisture retentive (mulched) bed.
“They are great woodland plants or even planted next to your home as a shelter from sun, especially on the east side or north side,” she said. “The newer varieties are more sun tolerant, like the panicle hydrangeas. Endless Summer varieties look like your grandmother’s hydrangeas but are more sun tolerant and repeat blooming.”
Moore lives where there is dense forest and a multitude of hydrangeas were thriving in the shade of massive trees. When her husband decided to build a shop, 25 40-foot trees were removed.
“The hydrangeas ended up in the sun, but they have done great,” she said.
Hydrangeas like water, but care must still be taken not to overwater. And they can continue to grow or they can be trimmed from time to time. Pruning suggestions differ depending on the species and flowering habit of the hydrangea.
Bigleaf (mophead and lacecap), oakleaf and mountain hydrangeas bloom on old wood or stems from the previous year. These require very little pruning. If it’s needed, it should be done shortly after flowering. For hydrangeas that are older than 4 years old, it is suggested you prune about a third of older stems to the ground and head back other shoots every year to increase bloom volume, help maintain size and improve plant health.
Climbing hydrangeas bloom on old wood, but can be cut back in early years after blooming to keep the plant from being too spindly. Smooth and panicle hydrangeas bloom on new wood, and may be cut to any height in late winter or early spring.
Learn more at extension.msstate.edu in the “Hydrangeas for Mississippi Gardens” publication, No. 2574.