How to Prune & Cut Grape Vines

Taste the grapes on your vine to determine if they are ready to be picked. As the University of Minnesota states, a grape will not develop any further once it has been harvested. You must allow the grape enough time to mature on the vine before picking. The color of the grape should not be used as a measuring tool for maturity, as the grape may turn color before it is ripe.

Slice the bunch of grapes from the stem with the sharp knife once they are ripe. Make your cut where the stem from the bunch of grapes meets the larger parent stem.

Prune out all broken, discolored and damaged branches once all the grapes have been harvested from the vine. Ideally, wait until just before the first frost, when the plant will grow dormant and store all of its energy in the roots and main stem.

Trim away all of the new growth for that season to maintain the size of your vine. Flower buds will only grow on wood that is at least one year old, so to keep the size, you cannot allow the new wood to age. To grow the vine, carefully select which new wood you wish to keep for the following year.

Weigh out the amount of wood you have removed that was damaged or new growth you wish to discard. Gardeners use a 30-10-10 formula, according to grapefacts.net. This means that for the first pound of wood you have removed, you have left 30 buds on the vine for the following year. For the next pound, you have left 10 buds. if you wish to have a large productive vine, stop at one pound; otherwise remove another pound.

Evaluate the cordons, branches that are spaced at least 6 feet apart, for spurs. These spurs are small shoots that grow out of the cordons and produce buds for the following year. The spurs only need two or three buds on them so the vine is not overcrowded. Cut the excess buds off just below where they have formed on the spur.