Early yields & dollars from a simple "V" the perpendicular-V training system for peach

Dr. Stephen C. Myers
Head, Department of Horticulture / University of Arkansas
Reprinted by permission of "American Fruit Grower"

Planting new peach orchards provides the opportunity to correct some of the limitations of traditional production systems. Orchard establishment is an opportune time to test new ideas.

Many issues revolve around the fact that production costs have risen faster than revenues. Peach growers are feeling pressure to lower production costs.

Low Yield With Open Center

In many types of production systems, yield increases have been a way to lower the per-unit cost. Yields for open-center peach trees are still relatively low.

Unlike many other tree fruits, however, peach culture has not benefitted from breakthroughs that provide dramatic increases in marketable yield. In particular, peach growers have not had the benefits of size controlling rootstocks to permit them to quickly fill the orchard space with a tree that is more efficient at converting light into fruit. Early yields per acre are an indicator of how fast allotted space is filled with a tree that is carrying fruit.

So how can we improve yields at the present? With open center trees, the most common method to increase yields is to simply let the trees get taller. This strategy still does not address the relatively long period of time it takes to develop such a tree (and yields) from the initial wide spacings traditionally used in this system.

V System More Efficient

A more efficient use of space is to modify the open center shape to an open V shape, often called the Perpendicular-V. In terms of shape, one can think of the open center as a circle and the Perpendicular-V as a straight line. It is easier to stack "lines" down the row than circles. With the Perpendicular-V system, row space is filled more quickly and efficiently compared to the traditional open center.

If you have not already established plantings of these systems, it is a simple matter to incorporate them into a new planting, as the between-row-spacing for the Perpendicular-V is the same as for the open center. The modification for Perpendicular-V comes from the closing down the in-row spacing to 5 ro 6 feet and limiting tree development to two scaffolds.

In addition to increasing early yields per acre, the system is also more efficient to manage because it is easier to develop more uniform trees. Being limited to two scaffolds per tree makes tree development simple and easy. Thus, tree to tree uniformity is enhanced, making it much easier to manage practices such as pruning and thinning. Each year, branches are pruned back close to the two scaffolds. Annual fruiting shoots start close to one of the two scaffolds, and have more than ample space to produce quality fruit as well as new shoot growth for the following season.

Plan Ultimate Tree Shape

5 ft.Photo compliments of Bennett Saunders, Piney River, VA.

In developing the Perpendicular-V, having a clear mental picture of the ultimate tree structure you want will help in choosing the correct training strategy.

A useful technique is to draw out the tree shape to scale on graph paper, using a protractor for scaffold orientation. This will help in establishing certain benchmarks for tree development.

For the open center system as well as for any other V-shaped systems, start scaffolds as close to the ground as possible. Doing so maximizes the use of an orchard's potential fruiting area and can lessen the need for severe bench cutting later.

Check it out on the graph paper. If you start a tree high, it will require more severe benching and a flatter limb angle to reach the desired tree height. Flat scaffolds and bench cuts will develop waterspouts and more upright scaffolds develop top dominance, both problems in tree development and light management.

Ideally, scaffolds should be developed at approximately a 55º angle. This development of scaffold orientation should minimize the use of bench cuts. Otherwise, such areas will be an annual source of watersprouts and shading.

Summer Training Management

During the summer, go through the orchard several times to ensure continued development of permanent scaffolds. This includes suppressing vigorous, upright shoots. In first-leaf trees, early selection of the desired number of scaffolds results in larger scaffold diameters by the season's end, in comparison to trees in which large numbers of scaffolds develop. In addition, excessive scaffold numbers mean that growth was wasted and corrective pruning will be required.

Throughout the first growing season, summer pinching can be used to direct growth into the permanent scaffolds and to develop the desired scaffold orientation. A few trips through the orchard over the summer will help to ensure that undesirable growth is checked early and will decrease the severity of dormant pruning required. Further, summer training will ensure that the permanent scaffolds develop size as rapidly as possible.

Additional training may be necessary where scaffolds start to bend over due to excessive weight. Also, tree limbs can be tied up to ensure a more ideal angel.

In Japan, Perpendicular-V trees are trained with bamboo stakes to avoid the need for bench cuts. Other training techniques used to help develop scaffold orientation include use of weights, rubberbands, rubber-tipped spreaders, and tie-downs. Keep in mind, however, that all these training techniques can require significant labor costs.

Dormant Season Management

Continued terminal development of the primary scaffolds should be ensured, in part, by removal of stronger upright shoots which will compete with the upward and outward development of the scaffold terminal. Any unwanted shoots on the trunk and at the crotch should also be removed.

If well-conceived and effective summer training practices have been used, heavy pruning will not be necessary in the following dormant seasons. Continue to develop scaffolds up and out toward the desired point of ultimate tree height based on the original design. Remove excessively vigorous shoots that threaten to dominate in the tree center and at the ends of the scaffold limbs.

Thin the ends of the scaffolds to single leaders. Remove hangers that are underneath the scaffolds in the lower half of the tree, and shorten those higher up if excessively long. Of course, pruning is often required to clean out the shoots that typically develop along the trunk and at the crotch area. This is ideally done in summer, when such shoots are not well-developed.

Certainly, many trees simply won't fit in with the "plan." Corrective measures will be required for such trees. But a clearly-defined plan for tree development will go a long way toward forming very uniform trees in as little time as possible, with permanent structural limbs properly positioned to support fruiting wood from the base to top of the tree. Maximum uniformity should be your goal, for such trees will be easier to manage and maintain with more uniform shoots, light environment, crop load, and fruit quality.

Growers should seriously consider the "Perpendicular-V" because of the system's potential for boosting early yields and increasing efficiency of cultural practices . Visit some folks who have tried the system to find out the pros and cons. But remember the only way to know if the Perpendicular- V will work for you is to try it.