Growing table grapes on your own backyard arbor is a fun summer project. The arbor works as shading, a landscaping structure or as a secluded Italian-style retreat for you and your guests. As grapes grow, they cover the arbor, creating privacy and a naturally intimate setting for an outdoor patio or picnic area. Using rot-resistant wood ensures your arbor lasts for years, as your grapes mature to produce the best fruits. With annual pruning, in three years your grape vines yield more fruit than you will be able to eat.
Cut the following board lengths with the circular saw: Four 2-by-6 boards to 9 feet 8 3/4 inches each. Four 2-by-6 boards to 4 feet long. Four 2-by-4 boards to 12 inches each. Eight 2-by-6 boards each 3 feet long
Lay the four 9 foot 8 3/4 inch boards into a square on the ground with the joining ends of two boards forming a 90-degree angle. Set the butt, or rough sawn edge, of one board along the face, or smooth side, of the perpendicular board. This leaves each side 10 feet long. Nail two 4-inch ring shank barn nails into each corner to secure the boards together.
Place the carpenter's square along one corner of the square you built in the previous step and line up the edges of the boards to square it. Place one 4-foot-long, 2-by-6 board across the corner at a 45-degree angle so that it overhangs two sides of the square. Bolt the board in place with two 4-inch spikes on each end. Repeat this process for each of the four corners.
Trim the overhang of the boards. Cut close to the original square with a circular saw, being careful not to gouge any boards.
Measure 15 inches from one corner of the square. Mark the measurement slightly higher than the middle of the 2-by-6 board. Measure 15 inches from that mark and mark again. Repeat the measuring and marking process until you reach the opposite end of that board. Repeat this measuring and marking process on the opposite side of the square.
Measure every 15 inches and mark slightly below the center on the remaining two sides. Drill 1-inch holes at each mark with the hole saw.
Cut 14 pieces of 3/4-inch galvanized conduit tubing to 10 feet long each. Drill a 3/16-inch hole 1 3/4 inches from the edge of each end of the pieces.
Transport the arbor to your desired resting place. Place bricks underneath each corner to support the arbor off the ground. Place a level on top of each side to ensure it sits evenly.
Hold one 4-by-4 post inside of the corner of the arbor square. Place a level against the post and adjust it until it is level. Press one #16 nail into the ground on each side of the 4-by-4. Measure 12 inches from the nails on each side of the arbor square and insert another nail for reference. Repeat this process for each corner of the arbor square.
Set the 4-by-4 posts aside. Move the arbor square out of the area. Move any other obstacles from the area.
Dig a 30-inch-deep hole at each of the four corners, marked by the nails, using the post hole digger. Place the removed dirt near the hole.
Set one 4-by-4 post in each hole. Hold the level against one post and measure to ensure it is 12 inches from each of your reference nails. Pack the removed dirt around the post, keeping it level. Tamp the dirt down to hold the post in place. Repeat the process at each corner.
Measure 8 feet up from the ground along one post. If one post seems shorter than the others, measure and mark that post. Hold a piece of conduit at your mark and extend it to the next post. Hold the level on the conduit to keep it even and mark where it touches the post. Repeat this process to mark all four posts. Cut the post along the line.
Nail the 12-inch 2-by-4 pieces to the corners of the top of the arbor square. Cut off the overhang. Lift the arbor up and onto the posts. These pieces hold the arbor in place temporarily.
Cut a 45-degree angle on the end of each 3-foot-long 2-by-6 board. Hold one angled edge even with the bottom edge of the arbor square and the other even with the post to form a brace. Secure in place with two ring shank barn nails. Repeat the process on each side of each corner of the arbor square.
Bolt the sides of the arbor square to the posts with lag bolts. Use three bolts total, two on one side of the post and one on the other at each corner. Space the bolts evenly so they do not touch when inserted. Put a washer on each lag bolt, insert and tighten with the wrench.
Slide one piece of conduit through each of the holes on the arbor square. Insert a golf tee into each hole in the ends of the conduit to keep it from sliding out of the arbor. Hang your vines or plant your grapes and train them to grow along the arbor.