Whether your garden is large or small, you can make better use of every square inch by using vertical gardening techniques to grow upright crops. Pole beans typically produce twice as many beans as bush varieties, and the right trellis can double cucumber yields. Then there are crops, such as tomatoes, that need some type of support to keep them above damp ground, where diseases have a heyday. All properly supported plants are easier to pick from and monitor for pests, plus you’ll get help from bug-eating birds that use trellises as hunting perches.
How Plants Climb
Plants that benefit from garden trellises use a variety of methods to cling to support, including curling tendrils, twining stems or, in the case of tomatoes, long, ropy branches that form roots in places that touch the ground.
Curling tendrils produced by peas and cucumber-family crops will twist around whatever is available, so you have plenty of versatility when supporting these crops. Tendrils cling to horizontal and vertical parts of a trellis, so netting woven from biodegradable string attached to posts often works well. Twining stems spiral around their support, growing steadily upward until they turn back on themselves — a growth habit seen in hops, pole beans, Malabar spinach and yard long beans.
Twining stems have little use for horizontal lines, so they do best with trellises composed mostly of poles or an upright fence. (See illustration in the Image Gallery.)
Tomatoes like to throw themselves over their support. They must be trained and tied to an upright trellis, which isn’t as easy as growing them in wire cages. The larger, more robust the tomato plant, the more you need a sturdy tomato cage that provides support on all sides.
Temporary or Permanent?
In my experience, a truly sturdy upright garden trellis must be anchored by T-stakes or vertical 4-by-4 posts (or 3-inch-diameter saplings from the woods), sunk 18 inches deep. Installing this semi-permanent garden structure takes time and muscle. In my garden, the most versatile trellises are about 8 feet wide, stand 4 to 5 feet high, and are made of woven wire fencing or a livestock panel attached to two posts. Allowing 4 inches of clearance between the bottom of the fencing and the ground makes the area easier to weed and cultivate. The advantages of such a trellis are the ready availability of the structure each spring and the option to make an attractive permanent feature in the garden.
The drawback of this or any other long-lasting vertical gardening supports (like an existing fence) is that it limits rotations to peas, beans, tomatoes and cucumber-family crops. Temporary trellises, such as bamboo tipis, give you more flexibility in terms of what you plant where, but they need to be taken down and stored in a dry place through winter to keep them from rotting. If you gather trellis parts and bind them together with string or strips of cloth in the fall and store them over the winter, they will go up quickly the following season.
I make a number of temporary trellises every year, often by looping cotton, hemp or jute lines around upright stakes or posts (what I call “string” is a ball of any of these natural, biodegradable materials). By using biodegradable materials, I can snip down the trellis and pull out the plants at the same time, then throw it all on the compost pile.
The most successful garden trellises increase the leafto- fruit ratio of the plant by allowing more leaves access to sun. A good support should also allow you to see and reach through the vines to harvest your crop, and it must be strong enough to hold its load.
Peas of any type (snow, snap or shell) prosper if grown on a vertical trellis made by weaving string into a grid attached to two posts, starting with the horizontal lines. The stakes should be as high as the variety is expected to grow, which can range from 2 to 6 feet. Small, bare branches stuck into the ground between plants will help lead pea seedlings to their support. Long-vined pea varieties often require extra support if they become top-heavy with pods. One easy fix is to add four stakes, one at each outer corner of the planting. These stakes can anchor a corral made of two or three horizontal runs of string, up to 5 feet from the ground. Pea vines that lose their moorings will cascade over the strings, where they are wonderfully easy to pick from. Last year I tried an old idea: using grains as pea supports. Overwintered cereal rye plants thinned to about 14 inches apart worked great, though you will need a tall pea to make use of rye’s 5-foot height.
To make the most of any pea trellis, “stack” the base of the trellis with both a short and a tall variety, such as ‘Sugar Ann’ snap peas with ‘Sugar Snap.’ The shorter variety will grow quickly, providing a little support for its slower-growing brethren, and it will start bearing just as the taller one begins to bloom.
Pole beans, runner beans and asparagus beans become extremely heavy at maturity. Upright trellises must be sturdy or they can be pushed askew by summer thunderstorms. There is perhaps no better use for an existing woven-wire fence than to use it to support pole beans. So-called half-runner varieties are a perfect fit for a 4- to 5-foot-tall fence. If needed for longer-vined varieties, tall stakes can easily be added to increase the fence’s height. You can attach these stakes with string to create a vision in vines. When I did this with a mixture of pole beans that produced yellow, purple and green pods, the result was delightful.
Beans take off when given a tripod or tipi-style trellis, which naturally resists toppling because it pulls downward on itself as the weight it bears increases. You should carefully consider height when planning a bean trellis. Nothing is worse than watching beans go unpicked because you can’t reach them without standing on something. You can control height to some extent by avoiding long-vined varieties, but you will need to limit the height of the trellis, too.
Personally, I have two favorite bean trellises: a humble, 3-foot-diameter woven wire tomato cage anchored with two metal fence posts for an early planting, and the stalks of sweet corn for a late-season trellis. Pole beans eagerly scramble up withering corn, and the corn doesn’t mind as long as you wait until it’s at least a foot tall to plant the beans.
Cucumber varieties vary in how well they take to a trellis. Large-fruited, burpless hybrids can be easily trained up an upright grid-type trellis made of string or wire. Just push the growing vines through the mesh about once a week. Smaller pickling cucumbers tend to branch more, making them more unruly to train. Woven-wire tomato cages contain their exuberance reasonably well, and make the ripe fruits easier to find.
Melons offer a unique opportunity to use diagonal, or A-framed trellises. Melon vines prefer to stay close to the ground, but raising them up protects them from diseases and insects that travel on the ground. Look for varieties that you should harvest at “forced slip,” which means the melons must be cut from the vine when ripe. Small-fruited honeydews are excellent candidates for trellis culture.
If your garden space is tight and you don’t think you have room for melons, think about connecting adjoining beds with an arch or A-frame trellis for this delicious summer fruit. This trick temporarily turns a pathway into usable, above-ground gardening space.
Tomatoes growing in woven or welded-wire cages need monitoring until you get to know a variety’s unique growing habits, because the same trellis that satisfies a compact ‘Juliet’ will be a disaster with a gangly ‘Brandywine.’ The top choice for homemade cages is concrete reinforcing wire, which will last for years, and the 6-inch-by-6-inch openings make picking easy. Make the cages in slightly descending diameters so they can nest together for storage.
Among ready-made cages, three-ring welded cages are adequate only for early determinate varieties. The four- and five-ring models can handle varieties of modest to average size and vigor, but most tomatoes will spew out the top and sides, and then start leaning toward the sun. Similarly, a lanky variety such as ‘Sun Gold’ can be trained and tied to an upright trellis or fence, but varieties that grow into dense, 6-foot bushes, such as ‘Black Krim’ or ‘Better Boy,’ need support on all sides, which is best provided by a cage. Even the best tomato cages become top-heavy when the plants are in full fruit, so they should be well-anchored to deeply set stakes.
Tall, non-vining crops such as peppers and cutting zinnias benefit from some support. This is where the small “tomato” cages can be helpful. Place one cage in each corner of a bed, then thread twine around and through the cages, making a support matrix for the leggy plants. (See illustration in the Image Gallery.)
Versatile Vertical Growing
Almost any garden can benefit from vertical gardening techniques: They save space, make harvesting easier, discourage soilborne disease, maximize production and encourage beneficial bird activity. Want more ideas? Building trellises from found materials has a long history at MOTHER EARTH NEWS, from a bean tower strung from a bicycle wheel to step-by-step instructions for making tomato cages from wire fencing.
Contributing editor Barbara Pleasant grows vegetables and flowers vertically in her southwest Virginia garden.