Answer: Grapes are normally pruned in late winter to very early spring. Grape vines produce fruit on new growth of the season, so they are normally cut back very short so that there are just a few growth buds. This will direct the plant's energy to just a few clusters and will also help keep it open for better air circulation. Often, the easiest way to do this and maintain a good form is to trim it back to near the start of the horizontal part of the trellis. That way it will develop a stout "trunk" with new vines radiating out from that every year.
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