Grapes grow on vines that must be supported by a trellis. You can create wire and post trellises of almost any length, depending on the number of grape vines you will plant. Each plant will need about 8 feet of horizontal trellis space. If you are planting a single vine, only use two post. If you will plant two plants, use three posts separated by 8 feet. Add additional posts to your trellis system for each vine.
The minimum number of posts for a single vine is two posts, spaced 8 feet apart. The largest number of posts depends on the length of your grape orchard. For example, an 80-foot orchard would support 10 posts, and vines, spaced 8 feet apart.
Dig 2-foot-deep post holes 8 feet apart for every grape vine you will plant. Use a shovel or post hole digger.
Place the posts in the holes and back fill the holes. Use a bubble level to ensure that the posts are straight. Place the bubble level against the post and ensure that the bubble is between the lines.
Drill holes from side to side 3 inches from the top and bottom of the posts. By drilling holes, you can thread your wire through a series of posts placed in a row to allow for the use of a single wire to support multiple grape vines.
Thread your wire through the holes and run the wire down the outside of the outermost posts.
Screw two stainless steel screws about an inch apart on the outside of the outermost posts. Leave about 1/4 inch of the screw protruding from the post.
Wrap one end of the top wire around one of the screws and one end of the bottom wire around the other screw. Make between four and five turns of wire around the screw to ensure that it won't come loose.
Go to the other end of your trellis and pull the wire taut. Wrap the end of the wire around the screws in the post on that end of your trellis. Again, make four to five turns of wire around the screw to ensure that it won't come loose.