Growing cucumbers on a trellis is desirable for many gardeners, since it takes advantage of limited space and also usually produces more cucumbers from your plants. Cucumbers are vining plants, so getting them to grow up a trellis is as easy as trellising beans, peas or any other climbing vegetable. The only difficulty lies in providing enough support for mature fruits when they appear.
Test your soil. Cucumbers prefer a neutral or slightly acidic soil, in a pH range of 6.0 to 6.5, and they do best in a rich, loamy soil. Sandy or clay loams are good, as long as the site you have chosen is well drained. Do any fertilizing or soil amendments needed before planting time to let them settle.
Place the trellis where it will be needed before planting the cucumbers. The trellis can be made of plastic, wood, wire and metal, or any other sufficiently sturdy material you have, but should be about 6 feet tall. If you are growing a whole row of trellised cucumbers, place support posts every 12 feet.
Plant after any danger of frost is past, as cucumbers are tender plants. The ideal soil temperature for germination is 70 degrees F, and best growth is produced at 75 to 80 degrees F.
Space the cucumbers 8 to 10 inches apart along the trellis, and place seeds about 1/2 inch deep in well-tilled soil. For seedlings, dig small holes with a trowel as deep as the soil they come in, and set the whole soil ball into the hole, firming up the hole with the soil you removed in digging. Water immediately after planting.
Train the main stem of the cucumber as it grows. At least weekly, check the plants and train as necessary. Use soft ties, not wire that can cut the vines, to tie the main stem of the cucumber to the trellis. Strips of rags, plastic twist ties or plain old string works well. Don't tie too tightly; enough to hold and support, but not bind.
Prune off bottom runners when the plant is young. This encourages upward growth instead of lateral vining. You probably will need to take off the first four to six bottom runners before the plant grows taller and begins to send out vertical runners.
Support the fruit when needed. As harvest time approaches, the cucumbers may become too heavy for the vine, causing splitting or breaking. Avoid this by making slings to put the weight on the trellis, not the plant. Tie wide strips of rags, pantyhose or cloth under the bottom of each heavy vegetable, and tie the ends to the trellis nearby.