Grapes are a fruit you can grow in your backyard. Some varieties, such as Thompson seedless and red flame, are delicious, nutritious snacks, but even one grapevine can become unruly, with its multiple, lengthy "canes," which grow every year and spread 15 or 20 feet in length. Building a trellis, or arbor, can be a fairly simple task that you can complete alone in under one day, and this project will not break the bank because it requires only a few supplies.
Measure the area where you want to build your trellis. If you have four grapevines spaced 3 or 4 feet apart, you can build a trellis that is 2 feet wide, about 12 feet long and 6 feet tall. A trellis this size will be all they need to support their rampant growth and make it easier for you to harvest their fruit.
Dig four holes with your post-hole digger at the corners of the area where your trellis will reside. Make your holes 1 1/2 to 2 feet deep.
Cut your corner two-by-fours to the length you want---if each is 8 feet long, it will rise at least 6 feet above the ground level after you sink it into its hole.
Insert the first two-by-four into the first hole. Begin sprinkling a ready-mix concrete into the hole. Slowly add water to the concrete in the hole and poke it through the loose concrete with a screwdriver or stick. Continue adding more dry concrete and water until the hole is full. Repeat for the other three corner posts.
Nail or screw two two-by-fours horizontally between each set of end posts for support. Cut your support boards 2 feet long, the same size as the width of your trellis. Place one board at the very top of your trellis and the second about 3 feet above ground.
Cut six 2-by-2-inch boards to measure 4 feet longer than your trellis. Nail or screw them equal distances apart along the top of your trellis to form a series of parallel horizontal boards that hang over both ends two feet. The grapevine will twine around these smaller boards when it reaches the top of your trellis.