How To Grow And Care For A Climbing Hydrangea

The hydrangea is the undisputed Queen of the Southern Garden. Whether you grow a big leaf hydrangea, panicle hydrangea, smooth hydrangea, or oakleaf variety, a well-tended hydrangea will give you lots and lots of gorgeous blooms throughout the summer. Looking across a yard at a bank of hydrangea bushes in full bloom is certainly a site to behold, but consider looking upward to the climbing hydrangea, a flowering vine that produces fragrant, lace-cap white flower clusters. Using the suckers on the branches, a climbing hydrangea will scale walls and other structures, sometimes reaching 50 feet tall or more at maturity.

Plant Attributes

• Common Name: Climbing hydrangea
• Botanical Name: Hydrangea anomala
• Family: Hydrangeaceae
• Plant Type: Perennial, Vine
• Mature Size: 60 ft. long, 6 ft. wide
• Sun Exposure: Partial, Shade
• Soil Type: Loamy, Sandy, Clay, Moist but Well-drained
• Soil pH: Acidic, Neutral, Alkaline
• Bloom Time: Spring, Summer
• Flower Color: White
• Hardiness Zones: 4-8 (USDA)
• Native Area: Asia
• Toxicity: Mildly toxic to people, toxic to pets

Hydrangea Care

Climbing hydrangea vines can scale tree trunks, sturdy trellises, arbors, and fences. The vines become large and heavy over time so be sure that the host structure can support the weight of the vines and the structure is not something (like the side of a clapboard house) that may rot or need replacing or repainting. The plants can also be pruned to maintain a shrub-like form. Climbing hydrangea can also be used as ground cover, taking root where the suckers make contact with the ground and filling in the area. Here is one more reason to love climbing hydrangeas: they are salt-tolerant plants and are very popular in seaside communities. The vines commonly don't bloom until they are three to five years old, so just be patient.

Light

Climbing hydrangea is one of the few hardy flowering vines that tolerate shade. In hot climates, choose a location where the plant will get dappled sunlight or partial shade. In the cooler regions of the South, the vine may do well with lots of morning sunshine if adequately watered. Climbing hydrangeas that do get more sun tend to bloom better.

Soil

Climbing hydrangea needs a rich, moist, well-drained soil. If your soil needs improvement, mix in a generous amount of compost before planting. Apply a 3-inch layer of mulch to help retain water in the ground around the root zone and reduce weeds.

Water

As with other hydrangea plants, this species likes constantly moist soil. Place it where it will get watered about 1 inch weekly, or even more often in hot weather. Interesting side note about the word hydrangea: the Greek root hydra refers to water, and angeon comes from the Greek for "vessel."

Temperature and Humidity

This plant is hardy in USDA plant zones 4 through 8 and does well in temperate climates but may wilt in hot, humid conditions. It can be damaged by sunburn and prefers daytime temperatures around 70 degrees Fahrenheit and night temperatures around 60 degrees.

Fertilizer

Fertilize this plant in the spring before the leaves begin to bud. Granular fertilizer with a high phosphorous count will create beautiful blooms. Fertilize again after the flowers have bloomed in the summer.

Pruning

As stated above, newly planted climbing hydrangea vines are slow to grow and slow to bloom. Once the plants are established, however, climbing hydrangea tend to be vigorous growers. You can prune them to keep them under control, but wait until summer after the flowers have finished blooming.

Propagating Climbing Hydrangea

Climbing hydrangea can be propagated by cuttings. Do this in the spring, when the plant has sent out new, tender growth, by following these steps:

1. Fill a seed tray with light potting soil or seed-starting soil and moisten the soil.
2. Sanitize a sharp pair of pruning shears with alcohol.
3. Select a green stem and cut sections that are 3 to 5 inches long, taking care to keep track of which end was pointing up.
4. Remove all but the top pair of leaves from each cutting.
5. Dip each cutting in rooting powder, then stick the bottom of the stem an inch or two into the soil of your seed tray.
6. Cover the tray with a clear plastic dome or piece of plastic and place in a warm spot in indirect light.
7. Mist regularly with a spray bottle to keep the soil from drying out. The cuttings should root in about a month, at which point you can transfer them to individual pots and gradually expose them to the outdoors.

Hydrangeas can also be propagated by layering in the spring, as long as you have a young, healthy branch that is close to the ground:

1. Gently pull a green stem down to the ground. Take a sharp, clean knife and nick the bark on the bottom of the stem where it meets the soil.
2. Remove any leaves in the area where the stem is in contact with the soil.
3. Use a hooked wire or landscape staple to pin the spot that you nicked tightly to the soil.
4. Place a brick or stone on top of the stem. Keep an eye on soil moisture and water when dry.
5. Once the stem has rooted, you can cut it from the mother plant just behind the roots. Leave the severed stem undisturbed for a week before digging it up and transplanting it.

How to Grow Climbing Hydrangea from Seed

To grow a climbing hydrangea from seed, use mature seed pods collected in fall. Fill a pot with moist soil and place the seeds on top of the soil. Cover the pot with a clear plastic dome or plastic wrap to help maintain moisture and place it in a warm room with indirect light. The seeds should germinate in about two weeks. Remove the plastic and water regularly to keep the soil moist. You can transplant in spring once temperatures begin to warm.

Overwintering

Before freezing temperatures arrive, give your moisture-loving hydrangea a good watering. Add a thick layer of mulch to preserve heat and moisture.

How to Get Climbing Hydrangea to Bloom

Climbing hydrangeas can take a few seasons or even a few years to get settled in and begin blooming in late spring or summer. Be careful not to prune the vine in fall, winter, or spring, as you may remove flower buds. Your hydrangea will set buds only if there are six weeks of temperatures below 65 degrees. A sudden frost can damage flower buds that are about to open. If your hydrangea is on the verge of blooming, cover it with a blanket or tarp until the cold snap passes.