Whether you grow your own vineyard, or just have a couple of grape vines on your property for fun, pruning them is the most important part about growing the vines. This is to ensure optimum fruit development and to maintain their shape. Although grape vines should be pruned all year long, there are certain things you need to cut back in the spring season.
Make sure you do not prune back your grape vines at any time during the first year of growth. You want the vine to grow wildly during this first year in order to establish strong roots, a healthy growth system and shape.
Prune all of the side vines and stems during the spring of the second year, except for the two strongest ones on either side of the grape vine's trunk. Encourage side growth at this time by pinching the vine's top.
Prune the top of the vine's main trunk during the end of the spring/early summer. This helps encourage maximum fruit yield. Prune back the weaker stems that are twirling up the side stems, as well as those crawling outwards on the ground or leaning to the sides. These will just suck necessary nutrients away from the stronger trunks.
Prune the grape vine the same way you did in Step 3 in the spring of the third year, trimming the same parts. Additionally, shape the grape vine with the pruning shears and scissors. This is necessary to keep the basic framework of the grape vine.
Continue pruning the grape vine in this way each spring season, in order to get rid of excess growth and to maintain the shape. Keep in mind that there is also intensive pruning to be done on grape vines in the winter in order for maximum fruit production.