Pruning and growing grapes
January 19, 2006
JAMES E. DENMAN - Victoria County Master Gardener
During the late '40s, I went to visit my grandparents who lived a mile north of Cheapside where they had a farm and did some ranching. In July that summer, I was coming from San Antonio by steam engine on the Southern Pacific Line and Grandfather picked me up in Westhoff. We returned to the farm and got the horses and wagon and headed out to pick Mustang grapes. They grew wild in the pastures and on the fence lines.
My grandparents made grape jelly, grape juice and wine. My grandmother could make the best green grape pies you would ever want to eat. This is a large part of why I am planting grapes on my farm, along with pecan and citrus trees.
I have recently researched the grapes to plant in Victoria and surrounding areas. The best performing varieties are the Black Spanish (Lenoir), Blanc Du Bois, Lomanto and Favorite. These are all red grapes except the Blanc Du Bois, which is white. There are many more, but these were recommended to me by Joe Janak, Victoria County Extension Agent, and local vineyard owners Friench and Martha Tarkington who live south of Victoria on Highway 77.

The Tarkingtons are a wealth of knowledge and information on growing grapes. In making your selections, be sure to check with your County Extension Agent and local nurseries as well.

Grapes are typically grown on an arbor or trellis to aid in air circulation, disease prevention and ease of picking. Growing grapes on an 8-foot-by-8-foot arbor that is also 8 feet tall can be interesting and productive in the landscape. A wooden arbor is best, whereas use of mesh wire for an arbor complicates pruning. Natural or unpruned vines on an arbor or trellis, while productive, will oftentimes produce fewer grapes than a pruned vine. An excellent Web site for how to design and build an arbor and prune grapes on an arbor is located at http://aggie-horticulture.tamu.edu/extension/homefruit/grapearbors/grape.html.

Grapes also can be grown on a trellis or fence using 8-foot end posts and 7-foot posts or tee posts for wire and vine support at each grape vine trunk. A 9-gauge galvanized wire set at 42, 52 and 66 inches from the ground will provide vine support. When planting grapevines on a trellis, the rows should run east to west for the best sun utilization.

Once the arbor or trellis is built, the grapes can be planted. When you get your plants, they will need to be planted right away so the roots don't dry out. Cut back the roots to 4 inches, and separate the roots as they should not be in a bunch. Dig your hole and only use the soil taken out of the hole to replant. During the first year of growth, a soil test should be performed for future fertility recommendations with no fertilizer used the first year. Grapes should be planted 8 feet apart.

Being knowledgeable of the makeup of a grape vine is important as well as helpful if you want to properly prune and train your grapes. Terms used in vine training include the trunk, which is the main base of the vine. The horizontal growth from the trunk growing in either direction on a trellis is called the cordon. The present season's growth and fruit clusters are called the shoots. A dormant 1-year-old shoot that has grown to 2-4 feet long and without leaves at pruning time in February is called a cane. This cane, annually cut back to have only two or three buds, is then referred to as a spur. Suckers or waterspouts are shoots that often develop at or just above ground level and they should be removed as soon as they develop.

The reason pruning at planting is important is to establish a sound, hearty root system providing healthy vines. According to Larry Stein, extension horticulturist from Uvalde, immediately at planting, cut the top back to only two buds on the strongest cane. Remove all other canes. The second year, just prior to bud break, the vine should be pruned gain to only two buds on the strongest cane. All other canes and buds are removed. This combination of root development for one full year and heavy pruning forces very rapid and strong growth the second year. As a result, training is very easy. When all of the shoots are more than 18 inches long, select the strongest and very carefully tie it to the stake, removing all other shoots.

In pruning a grapevine growing on an arbor after the first two years, essentially a single trunk grows to the top of the arbor and then it is pruned annually to a single cordon on top of the arbor with about 30 two-bud spurs left throughout the length of the cordon.

For trellised grapes, once the trunk is formed it can be trained and pruned to a number of systems, the most common being the bilateral cordon, which has two cordons growing horizontally off the trunk at the 42-inch wire. Each cordon is pruned in February to have seven spurs with two buds each. Stated in the most simple of terms, grapes are pruned by removing 95 percent of the canes in late winter just before bud break. If too much wood is removed, the vine will be excessively vigorous. On the other hand, if too little wood is removed, the vine will overbear. It is better to remove too much wood than not enough, because overbearing will weaken the vine as well as produce lower quality fruit.

Table grapes should always be over-pruned to increase the fruit size.

While pruning may sound complicated and is somewhat hard to explain, it really is not difficult and seeing the end result on someone else's vine is a big help.

Other grape-growing tips


Keep the area clean of grass and weeds, putting out a thin ground cover of mulch, irrigating your grapes as needed and fertilize from the second year and beyond.

Know and understand the basic steps of preparing your grapevines to have a successful and productive crop of grapes whether pruned on an arbor or on a trellis. Hopefully you, too, can enjoy some green-grape pie.