(News article for December 26, 2020; edited)
I often advise people to do winter pruning in the late January to early February period, while plants are dormant and shortly before they start actively growing again. Pruning can encourage a plant to start growing earlier than it otherwise would. If we get a warm period during the winter and the plant starts growing early, this puts it at risk for low temperature injury during late cold snaps.
However, as people who have pruned muscadines are likely aware, muscadines often “bleed” sap when pruned late in the dormant season. This bleeding is widely understood to not be harmful to plants, but if you want to avoid having vines bleed, you can prune earlier during the dormant season. Now-retired LSU fruit crops professor Dr. Charlie Johnson used to suggest pruning muscadines between Thanksgiving and Christmas.
Pruning well-maintained muscadine vines can be fairly simple: Cut back the previous season’s growth to “spurs” with 2 to 3 buds. Remove tendrils that are wrapping around the trunk or permanent arms (“cordons”) of the vine.
Muscadines fruit on shoots that come from the previous season’s growth. Even if muscadines are pruned each year, the wood from which the fruit-bearing shoots grow will generally get farther and farther from the cordons with each successive year. So, those spurs eventually form spur clusters, which look kind of like antlers. Once a vine is five years old or so, remove some of the spur clusters to encourage new growth to arise closer to the cordon.
In reality, many muscadine vines have not been pruned every year. If the vine is to the point that the fruiting wood is far from the permanent structure of the plant – whether the vine is on a trellis or an arbor – the vine can be renovated.
Renovating a muscadine vine involves cutting a “permanent” arm back to an approximately six-inch stub and, after growth resumes, selecting a shoot that grows from the stub to serve as the new permanent arm. During the summer, remove new shoots – among those coming from the stub – that you don’t plan to use as the permanent arm so that they don’t compete with it. This shoot will not produce fruit in the first growing season, but renovation allows you to re-train your vine for future productivity.
Let me know if you have questions.
Contact Mary Helen Ferguson.
The LSU AgCenter and the LSU College of Agriculture