The Most Common Grape Vine Growing Trellis Systems


Vineyards around the world utilize different types of trellis systems for growing grape vines. Although there are differences between each of them, they all have several things in common. First of all, one purpose for the trellis, regardless of style, is to support the weight of the vines and fruit, which will aid in the growing and harvesting processes, as well as helping to manage vines for pest and weed control. In addition, because the grapes that are being produced are affected by the amount of sunshine the vines receive, a trellis is important to maximize the exposure of the leaves. In this way, the ripeness, flavor, aroma and color of the grapes can be optimized by the grower. Throughout past generations, varied forms of trellis systems have been developed, customized, altered and used. Following are the most common types of trellises used today.



Guyot System

Named after Dr. Jules Guyot, the Guyot trellis is commonly used today, and is known for being a simple, easily managed system that produces smaller yields of very high quality grapes. Two canes are trained to grow in opposite directions from the trunk of the vine. These canes grow along wires running just above the trunk, and produce shoots that will then be trained to grow up to guide wires running above the canes. The benefits of this system are the ability to control the placement of the shoots for the best spacing and exposure for sunshine, and allowing the bunches of fruit to hang beneath the leaf canopy, where they receive good air circulation and controlled amounts of direct light.

Vertical Shoot Positioned System

Sometimes referred to as the VSP, the vertical shoot positioned system is similar to the Guyot system in the way it trains shoots to grow upwards towards guide wires. Four canes which will produce fruit are trained to grow in opposite directions on wires extending on two levels. The canes are sometimes sheared along the top, giving the vine a hedge-like look. This system calls for spur or cane pruning. The grapes will then be produced below the leaves, and several feet off the ground.

Gobelet Method

This very old system is found mostly in warm, nutrient poor soil areas, where the risk of rot, mold and other leaf diseases is lessened. One reason for this is that the bushy nature of this type of system doesn't allow for as much air circulation or sunlight exposure as typical trellised vines. Also, high quality soil would produce an abundance of foliage which would be forced to grow on the ground. The word gobelet translates to goblet, and comes from a description of the shape of the vine, which is trained without wires or other support systems. The trunk of the plant is very short, and is topped with a lump of knarled wood caused by years of pruning the few shoots at the head of the stump. This, called 'head training', produces a small shrub, which many call 'bush vines.'

Cordon System

In the cordon training system, the grape vines have a short trunk, as they do in the gobelet system. However, head training is not used, but rather a dominant branch, or cordon, is trained to grow on a wire along one side of the trunk. Some growers use one cordon, and others use two. From the cordon, which is not pruned, spurs grow which will require spur pruning. Many grape growers using this system prefer the uniform height of the spurs on the cordon, making mechanical pruning much easier.

Geneva Double Curtain System

In the 1960's, Dr. Nelson Shaulis developed this system with the intention of limiting the shade in the vine's canopy by splitting the foliage into two sections. Also called GDC, the process calls for a tall trunk which produces two cordons, which will be permanent. These cordons are trained to grow along guide wires about a yard apart. Spurs along these cordons will yield the canes that produce the grapes. These drape downward toward the ground, so that the canopy is now divided into two curtains of vine, increasing the sunlight exposure, and thus both the quality and quantity of the fruit. Because of this, Old World vineyards utilize this method less than the New, as the tight regulations in regard to yields restrict them.

Lyre Technique

Similar to the GDC, the lyre trellis system was developed in the 1980's. The advantages of this system are further improvements within the microclimate of the canopy, specifically the controlled amount of shade on the leaves and fruit. The trunk is divided into two parallel cordons again, but at a lower level, so that the canes that grow from the cordons are trained to grow upwards, instead of hanging down. These vines may be either spur or cane pruned.

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