I’m convinced that virtually everyone is born with a gardening gene. For some, however, it’s mid-life or later before the gardening gene switches on. And becoming a gardener late in life can lead to frustrations. My brother, a retired architect, is a classic case in point.
He was having a garden-induced meltdown when he called recently.
“Plants are worse than kids,” he snapped. “They clearly want more than I can give them.”
I calmly assured him that gardening, to be fully enjoyed and stress-free, was as much about process as results.
“Well, that’s just dandy,” he said. “But please tell me, in plain, simple English, how to prune hydrangeas so they will bloom?”
“Would you like the short or long answer?” I calmly asked.
“Short!” he demanded.
“Prune them several weeks after they bloom,” I replied.
Following a long sigh, he hung up, apparently to go and bludgeon a hydrangea or two.
I’m glad big brother requested the short answer. I’m not sure this late-in-life gardener could have handled the long answer.
There are four broad categories of hydrangeas generally found in the nursery trade — Big Leaf Hydrangea (Hydrangea macrophyla), Smooth Hydrangea (H. arborescens), Panicle Hydrangea (H. paniculate) and Oak Leaf Hydrangea (H. quercifolia). Ideally, we prune hydrangeas from each category a little differently.
Bigleaf Hydrangeas, the most commonly grown hydrangeas in local gardens, set flower buds in late summer or early fall and bloom in the spring. Prune big-leaf varieties several weeks following late spring or early summer bloom. Do not prune them in the fall or winter. End-of-year pruning will remove floral buds and prevent spring bloom.
Good news! Plant breeders have developed new Bigleaf Hydrangea varieties that repeated bloom on new growth. Endless Summer, Nantucket Blue and Let’s Dance are favorites of mine. Each new cycle of growth produces new floral buds and new flowers. Wise gardeners buy only repeat-blooming varieties of Bigleaf Hydrangeas.
Smooth Hydrangea also is a repeat bloomer. Hydrangeas in this category tend to tolerate more sun and moisture stress than Bigleaf types. Smooth Hydrangeas may be pruned in spring or fall. Personally, I prefer to prune them in the spring, typically back to 12 to 15 inches. The old Annabelle variety is a great choice for local gardens. Invincible Spirit also is a dandy. It produces beautiful pink flowers.
Panicale Hydrangeas, also known as PeeGee Hydrangeas, are becoming increasingly popular. They are robust plants with excellent winter and summer hardiness. They too repeat bloom and may be pruned in winter or early spring. Phantom is my favorite Panicle Hydrangea. It produces massive flower spikes 15-18 inches in length in early summer. Limelight is another great performer. If left unpruned, these two great shrubs can grow 6 to 8 feet tall and wide.
Oakleaf Hydrangea is a North American native that shines all year long with white to pink summer flowers, vibrant red fall foliage and colorful exfoliating bark. It thrives in sun or part shade and grows quite large, 6 to 8 feet in height and spread. I do little pruning on this species, just enough to maintain its shape. Mid-summer, after it’s through blooming, is when to prune this great American native shrub. Dead and damaged branches on any hydrangea may be removed throughout the year.
Barry Fugatt is director of horticulture at the Tulsa Garden Center and Linnaeus Teaching Garden. He can be reached by email: firstname.lastname@example.org.