My garden is full of hydrangeas. I realized this as my four-year-old granddaughter, Autumn, and I walked through my garden admiring the flowers. Over and over she asked, “What’s that?” and over and over I answered, “A hydrangea.” I guess I have gone a little overboard on these beautiful shrubs.
Oakleaf hydrangeas (Hydrangea quercifolia) are the easy to love hydrangeas in my garden. They do best in part sun but they tolerate deep shade as well, which makes them extremely useful to those of us who have mature trees and garden underneath them. The flower heads are elongated cone trusses made up of individual florets. These cones can be loosely populated with white flowers or so solid they look like they will burst.
The leaves, shaped somewhat like oak leaves on steroids, are large, drooping down to cover much of the stems. In the fall, the foliage turns to deep burgundy. After the shrub sheds its leaves in winter, the bark is visible. It looks like a large, clawed animal has shred it.
The oakleaf is a native shrub. It likes good woodsy soil and dislikes wet, heavy soil. If you garden in clay, as I do, just amend the soil with plenty of compost or rotted leaves. Oakleaf hydrangeas need some watering when rains are sparse, but they do not need much. Top-dress the roots every year with leaves or compost to mimic its natural growing conditions in woodsy soil.
Three of my favorite oakleaf hydrangeas are selections:
I first fell in love with the huge flower heads of Hydrangea quercifolia ‘Harmony’ at the Atlanta History Center gardens. I guess its common name is Sheep’s Head Hydrangea and it is apt. (I just call it Harmony.) The flower heads are packed full of florets. It needs some morning sun to develop into a sturdy shrub. Mine is in full, deep shade, so it has not become a full shrub. It has an open habit. I do get several huge flower heads, which is why I grow it. The heads are so full and heavy, they droop and sometimes need to be staked. This photo was taken a few days ago. The flower trusses are not fully open but already are extremely showy.
Its hardiness zone is USDA Zones 5-9. It is not quite as hardy as other oakleaf hydrangeas so plant it in a protected spot in its more northern range. Harmony is not easy to find but it is worth the search. I ordered mine from Wilkerson Mill Gardens. It is also listed at Rarefind Nursery
Hydrangea quercifolia ‘Little Honey’ is a dwarf oakleaf hydrangea I grow for its lime green foliage. It does have normal white flowers, but the large yellow leaves, which turn to chartreuse, are the show-offs in the spring and early summer garden. They light up a shady spot. Mine is planted under a tree and did take a few years to be established.
Since it is in such a shaded area, the leaves will darken to more green than lime as the season progresses. If you receive a small potted plant, grow it on in a container until it gets some size. It can be slow to get growing, even once it goes in the ground. This is another oakleaf worth the search and wait, in my opinion. Once it is established, it will do well in the dry shade under a tree. USDA Zones 5-9.
Hydrangea quercifolia ‘Snow Flake’ has been the most popular oakleaf hydrangea in my neck of the woods for many years. Master Gardeners love this extremely showy selection. The deep green foliage is a perfect backdrop for the long weeping flower trusses. The white florets double up layer on layer and last for weeks before turning beige. Give it shade and a little water to keep it happy in USDA Zones 5-9.
All of my oakleaf hydrangeas are planted in native clay soil and topped off with organic fertilizers or humus every year. Although I have read that these woodland shrubs should be planted high, I didn’t read these opinions before I planted mine. They are planted at the regular depth I plant most shrubs.
If you want to add any of these hydrangeas to your garden, remember, they do not ship well in the summer heat. Make a note to order these native charmers in late summer for fall delivery.
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By Joan Casanova, Bonnie Plants,
Photographs courtesy of Bonnie Plants, Inc.
Shorter days and cooler temperatures mean gardeners everywhere can flex their green thumb to squeeze every last moment out of the growing season. The experts at Bonnie Plants offer some fall gardening tips.
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