A trellis is a wood framework that is designed to support climbing flowers such as roses. A trellis can be as simple or as complex as you like. A simple trellis, however, works very well for supporting and showing off your climbing plants and flowers. Making and installing a trellis is not difficult and, in many cases, can be done in a morning or an afternoon.
Decide on the size of your trellis. Wood lattice panels come in a variety of sizes, most 8 feet on the long dimension. For example, lattice often comes in 1 foot by 8 foot, 2 foot by 8 foot, and 4 foot by 8 foot panels. Keep this in mind when designing your trellis.
Cut the height of your lattice panel to the desired height of the trellis. If you are making a 4 foot by 6 foot vertical trellis, measure 2 feet down from one end of the lattice. If you are going to mount the lattice on posts in the ground, measure and cut an extra inch off the bottom to keep the wood from coming into contact with the soil. Cut the lattice carefully with a hand saw. If your cuts aren't perfectly straight, use the cut ends at the bottom of the trellis.
Cut two lengths of 2 by 4 lumber the height of the trellis plus 3 feet. If your trellis is 6 feet high, cut 9-foot-long 2 by 4 posts if possible. You will place the bottom 3 feet of the posts in the ground. If you only have 8-foot-long 2 by 4s, don't worry. Bury the bottom 3 feet of the posts and allow the lattice to extend about a foot above the posts.
Lay the 2 by 4 posts flat and place your lattice on top. Screw the lattice to the posts 3 feet from the ends. Use galvanized screws to help reduce rust. Place screws at 2- or 3-inch intervals. If you are concerned about strength, spread a thin layer of wood glue where the lattice meets the posts.
Once your trellis is assembled, have someone hold the trellis in place and mark the locations of the holes for the posts.
Dig two 3-foot-deep holes for the posts with a shovel or post hole digger.
Place the trellis in the two holes and make sure it is level. If trellis isn't even, either dig one hole out a bit more or add soil into the other.
Refill the holes. Pack the earth tightly. Your trellis is built and installed.