Pruning Tips for Grapevines
As winter approaches, the time to prune grape vines takes a place on a home gardener’s agenda, said Maurice Ogutu, a University of Illinois Extension horticulture educator.
Pruning is the removal of canes, shoots, and other unwanted vegetative parts on the grapeviner.
“Pruning is the removal of canes, shoots, and other unwanted vegetative parts on the grapevine,” said Ogutu. “Grapes are pruned in late winter before the buds break. The objectives of pruning are to: maintain the vine in a desired shape and form to facilitate vineyard operations, ensure exposure of leaves to full sunlight, maintain productivity by making sure that the vine bear only the crop it can support and nourish, and to direct the growth of the vine into its permanent arms that will bear berries in the future.”
Ogutu noted there are two aspects of grape pruning. “The first one is to come up with a desired shape for the vineyard so that the vines can be arranged on a trellis,” he said. “This occurs during the first, second and third year of dormant pruning and is also a factor in pruning neglected vines.
“The second type of pruning is to control the size and quality of berries, which is done on plants more than three years old.”
Pruning of grapevines involves removal of dead and broken wood, and removal of last year’s fruiting arms that bore berries, as the two-year-old wood is not productive.
“Grape fruits are borne on one-year-old vines,” he noted.
It has been observed that canes growing outside the canopy are more fruitful because the buds have full exposure to sunlight, he added.
“Select one-year-old canes with darker colors and pencil-thick diameter as fruiting arms,” he said. “The number of buds or nodes retained on such canes depends on the vine size and vigor, but it is generally between 10 to 15. It is advisable to leave short renewal spurs with about three nodes closer to the trunk to produce replacement arms for the following year.
“Remove all the suckers arising from the ground around the trunk, and other canes except the selected arms and renewal spurs. Cut the selected vine to a desired length, and tie it on a wire trellis.”