Trellising cucumbers doesn't just free up space in the garden, it keeps the fruit off the ground. This makes harvesting easier and helps prevent ground dwelling insect problems as well as rot from sitting on wet soil. Your trellis doesn't have to be elaborate---a purchased lattice trellis is sufficient. Trellises should be at least 5 feet high in order to properly support the cucumber vines. Cucumbers can be planted a few inches closer when trellised as they won't require the space to sprawl.
Push the trellis 8 inches into the ground behind where the cucumbers will be planted. Attach stakes to either end of purchased lattice by twisting wire through the lattice and around the stakes. Create your own trellis by driving 6-foot-tall stakes into the ground on both sides of the plant or row, and then wiring concrete-reinforcing mesh or chicken wire to the stakes.
Plant the cucumber seedlings in front of the trellis. Guide the vines up and onto the trellis as the plants grow. (Installing the trellis first ensures there will be no damage to plant roots from driving in the stakes.)
Tie the central vine of the cucumber plant to the trellis loosely with fabric ties. Space ties approximately 6 inches apart. Guide suckers onto the trellis if they aren't wrapping around it on their own.
Harvest the cucumbers as they mature to prevent them from adding too much weight to the vine. Tie either end of a fabric tie to the trellis to form a sling and place nearly mature cucumbers in it for support if their weight is pulling down the vine.