Caring for your grape vines and vineyard during the summer

The world would be a better place if every human had a grape vine. ~ Henry Mitchell Pruning your table grape vines in summer is a small price to pay for the timeless look and abundant production of healthy grapes in your home garden. The vines, leaves, and clusters of grapes are all so evocative of the ancient world. Whether you're admiring your table grapes across the yard, or sitting under a grape-covered arbor, you're enjoying one of the great plants of history.

Follow these quick and easy steps for summer table grape vine care, then you can go back to relaxing and waiting for the tempting crop. In our video Tricia points out the lush table grape vine growth brought on by the wet spring and summer of 2011. Did that happen in your garden too? Are the long and lively grape vines grabbing at you as you walk by? To keep the table grape vines in your home garden under control, and boost their health, watch our video and use the timetable below for summer "canopy management". The canopy is all of the above-ground growth of the grape vine.

Pruning and Shoot Thinning in May and June

• Prune the shoots on the vines, with shoots about 3 inches apart.
• Remove leaves if there are more than 3 layers of leaves blocking sunlight to the lower buds in the leaf axils (which will produce the next year's crop).
• Snip all the sucker growth off the grape vine trunks.

Cluster Thinning

• A mature table grape vine can support only 16 to 20 clusters. Pinch or cut off excess clusters before they bloom.

Pruning, Hedging and Leaf Removal in June and July

Keep an eye on your grape vines as they grow. If the leaves become dense they can give too much shade for the clusters of fruit. If your climate is hot and sunny, like California's, you will want the clusters shaded by leaves for about half the daylight hours.

If you need to remove leaves, do so on the east or north sides of the vines; keep leaves on the west or south sides of the vines to protect the fruit from intense sun. Lack of air circulation from too many leaves is a factor in the development of powdery mildew (which can also lead to bunch rot). For more on powdery mildew prevention and cure, see our video and blog post.

Aim for shoots that are 3 to 4 feet long, with 15 to 22 large leaves. You can do summer pruning on your grape vines with your favorite garden snips and pruners.

• Lift the shoots with fruit clusters and arrange them on your trellis or arbor for optimum air flow.
• Shoots that have tiny clusters of grape "berries" need 15 to 22 mature leaves to feed the developing fruit.
• If there is too much leaf cover for good air circulation and sunlight, trim off leaves, or remove other shoots if they do not have fruit clusters.
• If you have excess shoots leaning over the top of your trellis, cut them to be about 6 to 8 inches long.

Cluster Thinning

• If you still have more than one cluster per shoot, cut off the excess now.
• Snip off the bottom of each grape cluster to make it round. This will improve the size of the fruit.

Protecting your grapes from birds

When the fruit starts to ripen, drape protective bird netting over your grape vines. For more information Watch Chuck Ingels, Sacramento County Farm Advisor, in a short video on both summer and winter grape pruning.