Blackwelder column: Now is the time to prune grapes

Published 12:00 am Friday, February 10, 2012

SALISBURY — Groundhog Day, Feb. 2, is generally considered by many as the time to prune grapes. However, grapes can be pruned later in the spring. Most grapes will benefit from judicial pruning now and throughout the growing season.
Pruning is a necessary maintenance chore that renews fruiting wood and prevents vines from becoming tangled masses of unproductive and often diseased wood. Pruning allows light necessary for fruit set. Air movement from annual pruning reduces the incidence of fungal disease problems.
Unfortunately, overgrown neglected vines cannot be miraculously cured with a single pruning. Overgrown vines often take years to recover from extreme pruning, so in most instances it is often easier to start over with new vines correctly pruned and trained from the initial planting.
Muscadine grapes or scuppernong type grapes are the most commonly grown grape in Rowan County. Most home gardeners like this type of grape because it is much easier to train and prune on an annual basis than bunch grapes. Indigenous to North Carolina, muscadine grapes have fewer disease and insect problems than bunch type grapes.
Muscadine grapes are often initially trained on a single wire trellis. Some homeowners use a double wire or clothes-line type for two rows. A single wire trellis requires less labor in pruning and is generally easier to pick.
Lateral canes trained along the wire trellis remain as a permanent cane or structure of the vine. This permanent lateral may grow to be very large, up to 2 inches in diameter. Many shoots will develop along this lateral. Each cane or shoot is cut back annually, leaving two to three buds per spur. Approximately 20 spurs should be retained for each 10 foot permanent arm. The location of the spurs is not important in muscadine grapes. When the laterals are correctly pruned, the cut vines appear to have a hair brush effect, with spurs pointing up and down. These spurs will produce the fruit and new canes each season.
With the unseasonably warm weather we’ve been experiencing, vines will bleed as the weather warms before the leaves begin to sprout. This will not injure the plant; it’s a normal part of the pruning process.
This type of vine is very easy to prune and maintain once permanent laterals are established. It is imperative that muscadine grapes be severely pruned each year to control growth, increase fruit set and keep vines healthy. For more information go to http://www.ces.ncsu.edu/muscadines/muscadine/production.html for more in-depth muscadine grape production.
Darrell Blackwelder is the County Extension Director with horticulture responsibilities with the North Carolina Cooperative Extension Service in Rowan County. Learn more about Cooperative Extension events and activities by calling 704-216-8970 Facebook or online at www.rowanextension.com
www.rowanmastergardener.com
rowan.ces.ncsu.edu