Climbing hydrangeas — low-maintenance, immense vines that create a lush blanket of foliage sprinkled with white lacy flowers — almost seem too good to be true. Although they take some time to start their impressive spreading, rest assured they are well worth the wait. These stunning vines can scale nearly any structure without causing damage, creating either a cozy backdrop or stunning focal point for your garden. It is rare to find a beginner-friendly plant that is as rewarding as the climbing hydrangea.
Growing much too large to be a potted plant, this impressive deciduous vine can reach 80 feet in height! Climbing hydrangeas grow heart-shaped green leaves behind their fragrant, flat-topped flowers. Their white buqouet-like flower heads can reach up to 8 inches in width, with small flowers blooming in the center and larger flowers around the outside. Ideal for covering walls, fences, and other vertical structures, these vines only need partial sun and require minimal upkeep.
Climbing hydrangeas survive in hardiness zones 4 through 8 and prefer living in partial shade. They can grow multiple stories in height, so make sure to plant your hydrangea in an area with ample space. Climbing hydrangeas grow clinging vines with aerial roots that help them effectively hold on to and spread over any non-metallic vertical structure. Before planting your hydrangea, make sure your structure is sturdy, since this species becomes quite heavy as it spreads. Climbing hydrangeas need frequent watering (around an inch of water per week) and do best in soil that is slightly acidic and consistently moist. Adding a few inches of mulch at the base of your hydrangea will help with moisture retention and weed control.
Once you've picked a spacious spot for your climbing hydrangea, dig a hole that is a few inches deeper than the vine's current root depth. Mix some compost into your hole before planting the hydrangea and after covering, add mulch to the base of the plant. Water your hydrangea right after planting and continue to do so frequently enough to maintain a damp soil. These plants typically take around 3 to 5 years before they start to grow or bloom at an abundant rate.
Climbing hydrangeas are wonderfully low-maintenance when it comes to fertilization. Typically, just adding a few inches of compost to the base of your vine once every year or two will supply your hydrangea with enough nutrients. Adding some granular fertilizer with a high phosphorous content in the springtime can help increase your vine's flowering rate, but avoid fertilizers high in nitrogen, as these will increase your hydrangea's foliage growth and stunt its flowering capacity.
You can propagate your own climbing hydrangea using a clipping from a healthy, established vine in the spring. Clip around 5 inches off the top of a branch of new growth that has not produced flowers yet. Ensure that the branch you select has multiple leaf nodes or the beginning of roots, and cut the branch 2 inches below a leaf node. Carefully remove all leaves except the top 2 from your branch. Prepare a planting tray with potting soil, loam, or seed and cutting compost and use a pen to make a hole in the center of the dirt. Dip the base of your branch in a rooting hormone, then place it in the dirt. Cover your tray with a plastic bag or a clear wrap, place it in a warm spot with low light, and mist the soil regularly. Once new leaves form, move your clipping into a bigger pot (6 to 10 inches) and increase its sun exposure. Once spring arrives and the weather warms, your climbing hydrangea can be transplanted to the great outdoors!
In the first few years, your climbing hydrangea will not require any pruning. Once the vine's rapid growth starts, pruning is often unnecessary, still, but can be done once a year in the summer, right after the plant blooms. If any of your hydrangea's branches die, get damaged, or become diseased, they should be removed; otherwise, prune based on aesthetic preference. Occasionally, branches may grow across each other and if the branches rub together, they can create spots that are vulnerable to pests or diseases; for this reason, you can also prune back crossed branches.
Keeping a few inches of mulch at the base of your vine is not only useful for water retention and weed control, it also keeps some diseases away from your hydrangea. Leaf spot, rust, and mildew are the most common fungal diseases found in climbing hydrangeas. These diseases can be seen in the foliage and stopped using fungicides. Pesky bugs such as aphids, weevils, spider mites, and scale insects may snack on your vine's leaves and stunt blooms. A few applications of an insect spray will get rid of most pests. Frost can also have a negative impact on your climbing hydrangea, but the only solution to frost damage is time.
If you have a large horizontal space to cover, fear not — the trusty climbing hydrangea will happily help you out. With nothing to climb, the aerial rootlets grown by the vine to scale structures will instead take root in the soil. When grown as a ground cover, the climbing hydrangea still takes a few years to get established, but once abundant growth starts, it will form a widespread, 3 to 4 foot high, mounding shrub.
The show put on by the climbing hydrangea begins in the spring, with the vibrant, light green new leaves that start to fill up the branches, and it never really ends. Next comes summer, when the leaves reach full lushness and turn a deeper green to contrast the blooming, bright white flower heads. In autumn, the leaves turn a festive yellow, while the flowers dry a reddish-brown. In the fall, the dry flowers can be cut and used as decorations or for arts and crafts projects. When winter comes around and the last leaves have fallen off your vine, you may think the show is over; however, the bark of the vine will start to peel, creating yet another unique look for your four-season plant.
Although standard hydrangeas come in many colors and flower-head shapes, the climbing hydrangea is its own unique variety. Also known as the hydrangea anomala petiolaris, this type is native to Japan, eastern Siberia, China, and South Korea. The name "hydrangea" has Greek roots and means water (hydr) and vessel (angeon).