They bend vines to their will, shape landscapes, and open portals in, to, and through vast gardens. They soften doorways, shape spaces, and create a sense of sanctuary.
And yet, trellises—a network of posts and rails used to host and support a variety of vegetation—are unheralded, unseen, and frequently underappreciated.
But trellises—or “treillages” as they’re also known—are critical in so many garden settings, says Kenny Collins, owner and CEO of DabneyCollins Landscape Design.
“Treillages are exceptionally useful for dividing ‘rooms’ in gardens,” Collins says. “They represent one of the most effective methods for creating a sense of privacy or enclosure almost instantly, which is particularly beneficial for in-town gardens.”
No one really knows when trellises took root in landscape design. Some say they are the invention of 16th-century French vintners who needed a way to support and shape the grapevines in their growing vineyards. Others trace them to the Palace of Versailles in France, where Andre Le Notre, gardener to King Louis XIV, used them to great effect.
Regardless of their history, trellises can have a lasting effect on many Upstate gardens, Collins says. “When executed well, trellis work can last for many years and significantly affect the feel of a garden.”
Horticulturalist Brian Hillman of Hillman’s Landscape stresses Collins’ note about execution.
Lasting effects
“Anyone can buy and place a trellis,” Hillman says. “But it’s probably better to have a professional design and install one. If not, they may fall apart after a while, especially if they’re made of less durable material that cannot hold up under the weight of the vines.”
Hillman says Lady Banks’ rose, climbing hydrangea, crossvine, and confederate jasmine are some common applications for trelliswork, with confederate jasmine being one of the more cost-effective options.
And it’s no use hoping a mature vine will twine to a new trellis. “I’ve never seen an established vine ready to go on a trellis,” Hillman says. “A trellis must be properly planted and trained.”
To do that, Hillman plants a new vine on either side of a trellis before using horticultural tape to secure the vine’s cordons—those single stems with fruiting spurs—to the latticework, thus giving the vine a chance to integrate and envelop the trellis. “This process usually takes two to three years,” Hillman says. “Although some vines, such as confederate jasmine, do not take that long.”
A fully enveloped trellis can lose up to a foot of headroom, Hillman warns, so it is important to start with a trellis that is at least seven feet tall and a few feet wide. “Anything shorter means people have to duck when they pass under,” he says.
And, like Collins, Hillman says understanding the purpose of a trellis is key to successful application.
“Yes, there are trellises for single plants that are readily available at any landscaping supply store,” Hillman says. “But in this context, trellises are most used as an entryway into another space, whether that is a garden or a doorway. I love the fact that a trellis is a tool I can use that is both aesthetic and functional.”
Not all Trellises are the Same
Hillman says not all trellises are made of the same material, and many of today’s trellises are not particularly durable.
The weight of the vine, weather, exposure to the sun—all can degrade the trellis’s structure and lead to collapse. Instead, Hillman says professionals are more and more going with solid PVC trellising that is durable and holds up to the elements, followed by iron trellising. Wood and aluminum trellising are the least desirable, as both tend to degrade over time.
