When growing grapevines, it is necessary to the growth and development to have a proper support system. The type of trellis you build will depend on the grapevine variety, your space and amount of grapes you grow. Ideally, at least two grapevines should be grown together so they can encourage each other's growth. Keep in mind some important tips when building a simple, functional grapevine trellis.
Find the site for your trellis (unless the grape vines are already planted, and in that case, you must insert the trellis next to the grapevines). When picking a site for the trellis, keep in mind that the trellis should be positioned right for the angle of sun and type of soil your grapevine needs. Decide if you want 4 foot tall (best for cooler weather) or 8 foot ( best for warmer weather) tall posts.
Dig a hole 18 inches deep about the width of the post. Use the mallet to pound it into the ground, layering some gravel around the posts in the hole if possible for added support. Fill in soil around the edges of the hole and stamp it down firmly. Keep main posts about 10 to 15 feet apart for each grapevine.
Pound the anchor posts into the ground next to the main post, angling each slightly away from the main one so it can keep the wire taut. Wrap the wire twice around the top of the main post about 1 inch down from the top, then pull it to the anchor post. Wrap the wire around the top of the anchor post in the same manner. Keep in mind that wire this heavy will mold itself around the posts when wrapped tight enough.
Pull the wire as tight as possible, then use wire cutters to cut away the extra. An anchor post at each end is ideal for a two- to three-post trellis.
Take a new piece of wire and wrap it around the main post's bottom, 3 to 4 inches up from the ground. Tightly run this wire (which will be the support for the bottom of the grape vine) along the entire length of the trellis, continuing to wrap it around every post in the same manner as the main posts. Repeat this process at the top of the main post about 3 inches down. This will support the upper part of the grape vines. Trim off any excess wire after you pull and wrap the edges tightly.
Take the lighter catch wire between the two main wires, directly halfway up the posts. This supports smaller vines and makes pruning more organized and simple.