Summary: The climbing hydrangea has value in the landscape as a sturdy, ornamental clinging vine, slow to start, but once established firmly in the soil, becomes a vigorous grower.
The climbing hydrangea (Hydrangea petiolaris) has been growing in America since 1865, however it was not that long ago it was a rare find in the home garden.
Fortunately, gardeners have gradually begun to appreciate its value as a sturdy, ornamental clinging vine, and nurserymen across the country have propagating them. It is true, this climbing hydrangea vine is slow to start growth when young, but given a few years to establish itself firmly in the soil, it soon becomes a vigorous grower.
In the forests of its native Japan, it grows to the tops of 80-foot trees but in cultivation can easily be restrained to a much lower height. Unusual as vines go, with its profuse white flowers borne in June, lustrous green, heart-shaped leaves and enthusiasm for cool shade, it is a splendid specimen for planting on home grounds where space and facilities permit. It also boasts winter beauty, for although deciduous, it drops its leaves to reveal lovely, reddish, shredding bark. Therefore, never cut this vine to the ground in fall, as you may well do with bittersweet or five leaf akebia.
Climbing hydrangea is perfectly hardy as far north as Boston, Cleveland, Detroit, Chicago and the Pacific Northwest. It does equally well down to the mid-South, but in areas subject to long, hot summer droughts, it does not succeed.
Grown on Stone
Because this plant climbs by means of small rootlike holdfasts, it should never be grown on a wooden wall of any kind. But on stone walls, old fences, piles of rock or big tree trunks, it makes itself completely at home and there is valued as one of the best clinging vines. Trees ideally suited to it are ones like the American elm, whose trunk is unencumbered by limbs for some distance from the ground.
Twining vines can quickly strangle and eventually kill limbs or even trunks of many trees, but the climbing hydrangea, given a sturdy trunk with few branches (and good soil in which to grow), climbs the trunk without permanently injuring the tree in any way. However, if you plant this vine at the base of an elm, remember that the elm’s feeding roots are very close to the soil surface and that it’s necessary to keep these roots away from the young vine until it becomes established and can fend for itself. Because tree trunks themselves are beautiful, it’s certainly not advisable to cover all your trees with vines. However, on some properties one tree trunk might be covered with excellent pictorial effect.
White Flowers Of Visual Value
The white flowers, wherein lies the plant’s chief ornamental value, grow in flat heads measuring 6 to 10 inches across, They are profusely borne on lateral branches sometimes 3 feet away from the tree or wall and are evenly distributed over the entire vine from top to bottom. The small flowers in the center of the cluster are the fertile ones, and remind one of Queen Anne’s lace. The flowers on the perimeter are the sterile blooms. Large and prominent, they set off the entire cluster.
The beautiful leaves, lustrous green and heart-shaped (as already noted), are finely serrate along the margins. This leaf type, incidentally, is one of the major points of difference between this plant and the inferior Schizophragma hydrangeoides, whose leaves are neither lustrous nor heart-shaped and whose leaf margins are coarsely dentate. The two plants differ also in the number of sepals in the sterile flowers. The hydrangea blooms have three to six, schizophragma only one.
Non-Insect Plant
Fortunately, the climbing hydrangea is one of those plants which insects and diseases do not attack.
To Thomas Hogg, an American consul in Japan, goes the credit for first observing the merits of the climbing hydrangea and sending the vine to America – to the Old Parson’s Nursery on Long Island – in 1865. But because there was no wide demand in the US for this unknown plant, this first introduction was almost forgotten until the Arnold Arboretum received seeds from Japan in 1876 and later broadcast reported of its excellence.
Propagation by Seed
Propagation of the climbing hydrangea is best done by seed. These are very fine, ripening in fall, and should be collected just when the small capsules begin to crack open for the seeds are easily scattered by wind.
When a small climbing hydrangea vine is first planted, give it plenty of good loam and do not let it dry out in summer. It may be necessary at first to attach the runners to the supporting wall or tree trunk, but within a few years the plant will soon he able to take care of itself. Growth may be slow the first year or so, but if planted well, in sun or shade, it will develop into one of the most beautiful vines on the home grounds.
