One of the biggest pruning chores for many during this time of the year is pruning grapevines. Due to the popularity of muscadines in this area many have vines in their home gardens.
Muscadine grapes are native to the Southeastern United States and are a popular fruit throughout Eastern North Carolina. Muscadines are easier to grow than many other plants because they have a high tolerance to pests and diseases.
A common question during this time of the year is “when and how to prune muscadine grapevines.” Mature vines left un-pruned can become a tangled mess of non-productive wood. Pruning is the key to maintaining healthy wood that will produce fruit.
Mature vines should be pruned during the dormant season. In the past, there was concern about the vines “bleeding” if pruned too late during the dormant season, but it has been found that the vines “bleeding” or dripping sap after pruning cuts does not have a negative effect on vines. For those that do or have seen grapevines pruned properly realize that you are cutting a lot of growth off the vines. Cutting this much of the vine away can scare some people who are pruning vines for the first time. Grapevines produce a lot of new growth each year, so you need to cut away a large portion of last year’s growth to allow room for new growth next season.
The shoots or canes of new growth, which is where the grapes are produced, come from the buds set on the last year’s growth. During the dormant season, shoots from last year’s growth should be cut back to 2 to 3 buds. Shoots that arise from older wood usually do not produce fruit. The one-year-old wood is the only source of fruitful shoots on the vine. So, it is important to leave enough of last year’s growth to get grapes on the vines. You want shoots to be spaced out evenly across the arms, so you may completely take out some shoots that are too close to other shoots. Be sure to check the vines and remove any wood that is dead or damaged.
If you recently planted vines, you will want to train the vines to grow on the trellis. The first couple of seasons after planting, you should focus more on training the main trunk and arms of the vine on the trellis and not worry about getting fruit. You may have some fruit the first few years but training the vine first will be beneficial in fruit production in future years. After planting, prune to one stem and cut the stem back to 2 to 3 buds. As new growth begins, select the most vigorous shoot to be your main trunk and cut away the others. You can stake this shoot to encourage it to grow upright towards your trellis. When tying up the shoot, remember that whatever you use to tie the shoot avoid tying it too tight to prevent girdling the vine. Continue tying the shoot upright as it grows, while removing any side shoots. When the single shoot is just below the wire of your trellis cut the top of the shoot off. By cutting the shoot tip off you are causing the vine to produce side shoots at that cut. As the side shoots grow, select the most vigorous ones and train them down the wire, which will form your main “arms” or “cordons” on the wires. After the cordons have developed to full length, side shoots can be allowed to develop. Then let the side shoots grow and prune them back to 2 or 3 buds every year during the dormant season. Sampson County Extension Center installed a muscadine trellis system several years ago. Stop by if you are interested in seeing our trellis system and the way our vines are being trained.
Reminder: A new program for 2012 is the “Sampson County Friends of Horticulture.” This program offers monthly “How To” Horticultural Seminars. Please call (910) 592-7161 for more information. Please turn your radio to WCLN 1170AM every Monday, Wednesday, and Friday at 12-noon (that’s lunch time) and listen to the Sampson County Ag Minute segment, which is brought to you by the Sampson County Extension Agricultural Agents. Please call the Sampson County Cooperative Extension Center at (910) 592-7161 with your horticultural questions and to register for any upcoming events. Be sure to check out the Ask An Expert Widget at sampson.ces.ncsu.edu for any questions you may have.