Garden Guide

Grapevine pruning
Feb. 27, 2013 @ 11:16 PM

To those of you with grapevines, pruning can seem like a daunting task. There are lots of you out there with a grapevine or two in your backyard. Many of them need to be pruned.   

Why prune? What benefit will I get? Pruning removes old and unfruitful wood while allowing better airflow. This means that you will have healthier growth, less disease, and most importantly, more grapes!

Let’s start by explaining some terms. The trunk connects the upper parts of the vine to the ground and roots. Remove any suckers or watersprouts that may form off the trunk. The arms of the vine are either trained on a wire trellis or radiate on an arbor. If you have a double wire trellis, remove the lower arms. Research has shown that these arms do not bear as much fruit since they are shaded, plus they are a lot of work to harvest and prune. Canes are last year’s growth and can be identified by their lighter brown color and typically long length. Muscadines fruit on this wood (last year’s), so be careful not to remove too much!   

Unpruned, neglected grapevines look like a dense jungle of shoots. No wonder you are intimidated! The first thing to do when pruning is by working in small sections, to identify any dead, diseased or damaged canes. This year, we may see some cracked wood due to the cold temperatures Lee County has experienced. Freeze-damaged wood can be removed. Next, identify and remove any canes that originate on one side of the arm, but crossover to the other side.

Now that we’ve removed the easy stuff, it becomes a little more difficult. Choose from the canes left, ones with a pencil diameter to retain. Bigger is not better, but neither is twiggy. Ideally you would like to retain one spur per six inches. A spur is a shortened cane with 3-4 buds. You can identify buds by the slight swelling of the cane there. Buds will create this year’s shoots and fruit. Be sure to leave at least 300 buds per vine to ensure adequate fruit.

Another thing to keep in mind is the “bearer.” A funny word, yes, but there is no funny business here. Bearers are structures on the vine that have wood older than two years. Sometimes they resemble deer antlers. You want to decrease the amount of older wood on the vine since this wood is not fruitful. Remove bearers judiciously or leave a little stub in its place. Next year a bud will break closer to the arm and you will have younger wood.

The most important thing to keep in mind is that muscadines are quite resilient. If you make a mistake this year, they will rebound in greater splendor next year. Remember, 1) remove dead, diseased or damaged wood, 2) remove wood that crosses-over, 3) retain pencil-diameter wood from last year, and 4) decrease the amount of bearers. Don’t worry if your vine bleeds a little when you prune, this does not hurt the vine. The best way to prune is to learn. So go give your grapevine a haircut!

  

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