For about 15 years, a big yellow garage marked the southern boundary of our backyard garden. It set off the blue bigleaf hydrangeas very nicely, but it wasn't exactly the look we wanted.
The garage is still there, but you can't see it anymore. Nine years ago I planted a single climbing hydrangea a couple of feet from the base of the garage, and after a slow start it has almost completely covered the wall.
It might be the single most useful plant on the property. On the north side of a building, often a difficult gardening spot, it provides four-season interest and a breathtaking early summer floral display.
Combined with the holly hedge that runs along our east boundary, the climbing hydrangea brings something of a 'Secret Garden' feel to its corner, a lost-in-leafiness mood that is only heightened by the droning of bees. And it can be spectacular even at night, if the flowers catch the moonlight.
The vine is nearly care-free. It gets time-release fertilizer granules in early spring and late-summer, and it has to be watered during summer drought. (Our climbing hydrangea has never shown the tendency to wilt on hot afternoons that other hydrangeas have, maybe because it's always in the shade.) I keep it pruned to the top of the wall for fear it will push the roof off, and when I remember I cut it away from the garage windows.
No trellis or wires are needed for support, as the vine adheres directly to the wall.
In spring, handsome, serrated leaves seem to pop from the tracery of reddish-brown stems on the wall. As they multiply, branches grow out from the wall as much as 21/2 feet, giving the vine a three-dimensional heft.
In late spring and early summer, lacy white flower clusters appear. Each bears tiny fertile buds surrounded by a few larger sepals. Although at 8 or 9 inches they are as big around as the mophead flowers on some more familiar hydrangeas, the architecture is refreshingly different.
The flowers begin to darken after a couple of weeks, but remain a bright contrast against the dark green foliage for a month.
Eventually, they dry to a tan color and can be pruned off.
In fall, the climbing hydrangea's leaves brighten with yellow.
When I first heard about this plant, I was warned that it followed the rhyme often applied to perennials - 'sleep, creep, leap.' That implied I would see little growth at all the first year and just a bit the second year before the climbing hydrangea took off.
But to be honest, for me it was more like 'sleep, sleep, creep, creep, leap.' The vine did not show any of its astonishing spreading potential until its fifth year, and it did not flower until its sixth.