Many muscadine grape vines in our county are in need of pruning. Unpruned vines do not bear well and also are more susceptible to pest attacks because of poor air circulation within the canopy.
The daunting task of pruning may be a bit easier when you understand that the fruit is produced on new growth. Pruning encourages the new growth.
Muscadine flowers are produced on new shoots that grow from last year’s growth. Only a small portion of the previous season’s growth needs to be left for a crop to be formed. On young vines, the spurs (fruiting units that grow from last year’s wood) need to be shaped 4 to 6 inches apart.
Caswell Research Farm has a good example of young muscadine vines to help teach pruning and explore varieties. On the farm you will see basic muscadine plants that consist of a trunk and cordons (arms on the wire). It is on the cordons that the fruiting units (spurs) develop.
A workshop at 2 p.m. Friday will demonstrate the basic pruning recommendations: Cut back the growth from last year to spurs with two to four buds; remove canes entirely if they are not needed for fruit production or are in a poor position on the vine to produce high quality fruit.
All wood arising from the trunk will be removed to help maintain the vigor at the end of the cordons. While pruning, we will inspect the cordons to look for tendrils that may wrap around the cordon, and girdle (squeeze until it cuts off life) it.
This is a good time of year to prune muscadine vines because winter weather is about over. Some bleeding of the vines may occur at this time of the year, but research says it does not harm the plants.
Overgrown vines can be initially pruned with gasoline-powered hedgers or electric powered hedgers. This type of pruning is much faster than hand pruning. Additional hand pruning is needed for thinning overcrowded spurs and removing tendrils tightly wrapping around the cordon.
If vines have been neglected for several years, several strategies are available. One is to completely remove the old cordons except for a six-inch renewal spur at the head of each cordon. Allow new shoots to grow down the wire to form the new cordon. Prune the tips back when they reach the desired length.
The second option is to cut the growth on one side of the vine (left side) back to two to four buds of the previous season’s growth. On the other side, cut off all the lateral growth, leaving just a naked cordon. This will allow the left side of the vine to produce fruit.
Wait for the next season, bring the right side of the vine into production and cut the left side back to a naked cordon. In the third season, the vine will be completely rejuvenated and back to near full production.
Join us in the Muscadine Pruning Workshop at 2 p.m. Friday at the Caswell Research Farm Office. From Hull Road turn onto Goodson Boulevard and turn left onto Farm Lane. Look for the signs for parking. Dress for the weather and do not forget gloves and hand pruning equipment.
Peg Godwin is horticulture agent, Lenoir County Cooperative Extension Center. Reach her at Peg_Godwin@ncsu.edu or 252-527-2191.