Gardening on the Vertical
by Hilda J. Brucker
Vines are plants of ambition. Not content to remain earthbound, they will aim for the sky with leafy determination and the lofty aspirations of an aviator who has just earned his wings. Although often banished to the suburban mailbox, vines are wonderfully versatile plants. Needing just a footprint of earth for their roots, they can fit into spaces too small to accommodate shrubs, yet they are also capable of covering large areas. Are you bothered by an unsightly view? A vine may be just the leafy eradicator you need. Does your deck or patio broil in the noonday sun? A vine can provide welcome, cooling shade. Chosen with care and placed thoughtfully, vines are the workhorses and problem solvers of landscaping.
Even in a relatively small home landscape, a selection of climbers and ramblers can provide the following:
Clematis montana 'Rubens'
Seasonal color. While summer annuals can provide long periods of color, the more fleeting displays of flowering vines are also beautiful. The onset of spring is marked by the white, dogwood-shaped blossoms of evergreen clematis (Clematis armandii), or the pale pink flowers of Clematis montana. In warm climates, Carolina jessamine (Gelsemium sempervirens) is valued for early spring color -- its brassy gold trumpets appear anywhere from February to April. In late spring, wisteria takes over. Summer brings a myriad of choices for blooming vines, including hybrid clematis, annuals like morning glories, and such tender, tropical selections as bougainvillea and mandevilla, which will often bloom long into the fall before a killing frost cuts them down. Signature vines of the fall include sweet autumn clematis (Clematis maximowicziana) and silver lace vine (Polygonum aubertii), both of which produce a froth of many small, white flowers.
Fragrance. The sweet scent of wild honeysuckle (Lonicera species) has long been associated with summer nights. In home landscapes, the cultivated varieties provide showier blooms along with fragrance. When planting any scented vine, be sure to place them where their scent will be noticed. For example, plant jasmine outside a doorway that is used often, or next to a favorite sitting spot like a porch or patio.
Good use of small spaces. Because vines utilize the vertical dimension of the garden, even the tiniest piece of earth can accommodate a vine or two. A tiny yard can feature a beautiful flowering vine in many spots - against walls or fences, or on a lamp post or mailbox, for example. A favorite trick of savvy gardeners is 'doubling up' -- growing vines over shrubs, up small trees and on top of climbing roses. Not only does this allow you to pack more plants into a small space, it extends the season of interest (picture a late summer-blooming clematis growing intertwined with a spring-blooming lilac).
Privacy. A well placed vine can provide the same amount of privacy as a tall shrub, while taking up less horizontal space. For this purpose, be sure to choose evergreen vines, and train them to cover a trellis thickly. I once made a cheap-and-easy screen between my house and the neighbor's by stretching a width of chicken wire between two pressure-treated posts and then weaving ivy through it. As the ivy grew, the chicken wire quickly "disappeared," leaving a green wall. You can also extend the height of a privacy fence by adding trellising materials and an evergreen vine.
Shade. Where summers are hot, shade is a valuable commodity. Many types of vines, including trumpet vine (Campsis radicans) and Virginia creeper (Parthenocissus quinquefolia), grow with rampant abandon and can cover a pergola or arbor in a season or two, shading a patio or walkway more quickly than a tree could. Trumpet vine sports orange, trumpet-shaped flowers that attract hummingbirds but can become a nuisance as it spreads by underground runners, often emerging six feet or more from the parent plant. Virginia creeper is primarily a foliage plant, with five leaflets resembling the fingers on a hand. Deciduous vines can actually help to save energy. Their shade blocks the hot sun, reducing air conditioning costs all summer, while in winter, bare stems let the sunlight through, warming the house and lowering heating bills.
Camouflage. Vines give you the option of softening hard elements in the home landscape. Let the delicate foliage of Akebia quinata hide a utilitarian chain link fence (it produces unusual purple flowers in spring as a bonus). Or, let a climbing hydrangea (Hydrangea petiolaris) blur the rigid lines of a stucco wall. Homeowners with a ramshackle shed or unsightly garage could easily put this technique to work.
Clematis: Queen of the Climbers
Widely grown for their colorful flowers, clematis are among the most popular of vines. Perhaps most familiar are the modern hybrids with their large, showy flowers and restrained growth habit -- many will only attain heights of six to twelve feet, making them ideal for growing over shrubs and in other situations where a more rampant grower would smother its neighbors. Their blossoms encompass nearly the entire color spectrum and blooming times range from early spring to fall, depending on the variety.
In addition to the named hybrids, however, are the species clematis, which in my opinion are sadly neglected. Among the most charming of these are varieties of Clematis alpina, which produce abundant nodding, bell-shaped flowers, quite different from the open saucer-shaped blooms of the hybrids. Clematis alpina is usually among the earliest clematis to bloom in the spring. Another species, Clematis tangutica, also produces bell-shaped blooms, of a bright golden yellow, but blooms in the fall. It is the only yellow clematis.
One of the greatest differences between hybrid and species clematis is the abundance of bloom. While the hybrids produce a handful of large, showy flowers, species such as the spring blooming Clematis montana are literally smothered with blossoms, although they may be only an inch across. Another difference is plant vigor -- Clematis montana, sweet autumn clematis and the evergreen Clematis armandii all are capable of reaching to twenty or thirty feet. Choose a site for these carefully, and give all clematis with a cool root run. This can be accomplished by mulching the root area or overplanting it with a groundcover that will provide some shade.
Because there are so many different types of clematis, there is often confusion over when and how to prune. For pruning purposes, clematis fall into three main groups. Group one blooms in the spring on the previous year's growth. It does fine without pruning, but when shaping is desired, it should be cut back immediately after it finishes blooming. Group two blooms in early summer, with flowers forming on short stems that grow from the previous season's leaf axil buds. In early spring it should be cut back to a pair of strong buds on all stems. Group three blooms in the late summer or fall on the current season's growth. Because it produces flowers on new wood, it will bloom most profusely if cut back each year in early spring to between 12 and 18 inches from the ground.
While many gardeners choose perennial vines for their hardiness and reliability, others celebrate summer with Heavenly Blue morning glories (Ipomoea tricolor "Heavenly Blue"). True to their name, these vines open their glorious azure blooms at dawn, closing them again by midday - so choose a planting spot that you'll pass by when you leave the house each morning. They will give you a quick, spiritual lift that's almost as good as coffee.
A wonderfully rewarding trick is to plant morning glories together with their cousin, the moon vine (Ipomoea alba), whose large white flowers open late in the day. The vines do a good job of competing with each other and together they make for a more spectacular display. The morning glories put on a show until midday, and then the moon vines take over in mid-afternoon. Moon vine has earned its name from the way its flowers gleam in the moonlight or any other type of reflected light. It is easily started from seed using the same techniques as for morning glories. The seed for each germinates best in cool soil and seedlings can tolerate light frost. Like sweet peas, morning glory seed has a hard coating which should be scratched or nicked to help germination take place.
Hyacinth bean (Dolichos lablab), a vigorous annual vine, can quickly cover an arbor during one season. Its large clusters of lavender flowers are followed by large, reddish purple seedpods that are every bit as ornamental as the flowers themselves. It's commonly used by landscapers to make a big display in a first-year garden, before a perennial vine like wisteria is well established enough to make a showing. The fantastic growth rates of annual vines can be a great asset in a new landscape.
How Vines Climb
Before deciding on a support for a particular vine, you must understand how the vine climbs. Clinging vines, which include trumpet vine, climbing hydrangea and English ivy, adhere to a surface with tiny aerial rootlets that grow from the stems. They can damage wooden siding and weaken the mortar in a masonry wall and are therefore most safely grown on a trellis or other structure that is placed six inches away from the building.
Grasping vines, like grape (Vitis species), climb by grasping their support with tendrils. Clematis are also considered a grasping vine, as they use their petioles, or leaf stems, to grab onto their support. These types of vines can most easily grasp onto wires or thin lattice pieces that are spaced closely together. An ornamental trellis with wide open spaces should be backed with chicken wire or some similar material to help grasping vines get a toehold.
Twining vines climb by coiling themselves around their support, and do well on chunkier supports such as lamp posts and porch pillars. They will also weave themselves in and out of open latticework as they head in an upward direction.
Use the following technique to transform a lamp post into a lush pyramid of flowering vines: Drive several stakes into the ground, forming a circle around the base of the post. String twine from the stake to the top of the post. Plant a seedling next to each stake, and as the seedlings grow, coax them up the twine. You'll get a much fuller look this way than if you were growing them directly on the post.