More in Outdoors
Cut two pressure-treated 4x4 posts to the desired height, including the part of the posts that will go in the ground. Cut two 2x4s to the width of the trellis grid. Lay out the posts and 2x4s to form a box, with the 2x4s on edge about six inches from the top of the posts. Assemble the frame with screws. Be sure to measure and line up the posts and 2x4s carefully to keep the trellis from coming out crooked. Leave six inches above the 2x4 at the top of the posts for post caps. Use rust-proof screws and nails for all parts of this project.
Rip each of the extra notched boards lengthwise with the table saw. Line up four of these notched pieces around the inside of the posts and 2x4s, notched side up. Fit the trellis into the notches, then fit the other notched boards on top to sandwich the trellis grid. Line everything up and drive decking screws through the notched boards into the posts and 2x4s to secure the trellis. Countersink the screws to hide the screw heads and help keep the wood from splitting.
Determine the final location for the trellis, dig post holes and insert the posts in the holes. Backfill securely, and the trellis is ready for roses or other climbing plants.