Vertical Gardening Tips

Image Gallery You can achieve greater harvests with vertical growing. The author's favorite type of plant support, the sturdy woven-wire trellis, is durable enough to last for years. PHOTO: PAT STONE

A few years back I was leading an old friend through my garden, all the while bemoaning my lack of growing space, when he suddenly interrupted me and asked, "Why do people build skyscrapers?" What this had to do with my overcrowded garden, I hadn't a clue. "So they can cram a lot of people into a place without using up much ground room?" I ventured.

"Exactly. Sort of like your garden, wouldn't you say? You've got acres of unused space—in the air."

My friend was right. The extra room I needed was literally right in front of my eyes. I started "growing up" and soon found that vertical gardening has many benefits. It increases yields: Most climbing vegetable varieties bear heavier and longer than bush types. By providing better aeration, it can reduce disease. In one study, North Carolina State University researchers found that trellised cucumbers (which also had the bottom foot of foliage pruned) produced much healthier plants, and twice as many fruits, as untrellised vines. Vertical growing also creates cooler microclimates for understory crops. And it adds visual appeal to the overall garden.

One more thing: Most bush varieties were bred from climbing ones, and many growers think the original climbing cultivars have better, old-fashioned flavor. As a seed-saver friend of mine once put it, "Why stoop to pick inferior-tasting peas?"

Of course, short varieties do offer some conveniences. Since those bush beans, dwarf tomatoes and other determinate varieties cease growing at a set height, they're often able to stand on their own. And they bear all at once rather than over an extended period. But to my mind, the benefits of trellising crops are well worth the efforts.

Best Trellis Supports

For plants to grow up a trellis or other support, you first have to build it. Most have two parts—the main structural framing and some form of internal netting.

Some common supports are wood posts, metal stakes and thick-walled rigid PVC pipe. Rot-resistant black locust, cedar and redwood all make long-lasting wooden posts, but almost any sapling tree trunks (three to five inches in diameter) will give several years of service—more if brought inside for the winter. Treated posts are also available commercially. For each post, dig a two-foot-deep hole (a posthole digger is the best tool for this job), set the support in place, and tamp the dirt around it with a stout pole or rod. Horizontal slats nailed to the underground portion of these posts will add extra stability in sandy soil.