54663 853 Road
Pierce NE 68767
402-329-6774
Hours:
January-April
Friday, Saturday and Sunday 1:00 pm-5:00 pm
May-December
Wednesday-Saturday
11:00 am-6:00 pm,
Sunday 1:00 pm-6:00 pm
Closed Easter Sunday, Thanksgiving Day, Christmas Eve Day, Christmas Day, New Year's Eve Day, New Year's Day, Super Bowl Sunday
Vertical Shoot Positioning for Nebraska - A quick overview of Pruning and Training
Training - puts the crop in an economical and convenient position.
In order for a training system to be economical it must also be sustainable
Pruning - controls the size of crop.
What are the criteria for choosing a VSP system?
Situations that have medium to medium+ vigor.
Cultivars that have an upright to semi-upright growth habit.
Cultivars of questionable cold hardiness.
What are the advantages of VSP?
Good cross ventilation through vines and underneath vine rows. With proper shoot positioning all shoots area kept from between the cordon and the vineyard floor, increasing air movement and thus causing less problems with disease. Also increased air movement in the canopy helps vines to dry more quickly after wet periods.
Exposing area in leaf axil between June & July for optimum fruit bud initiation for next years crop.
Good fruit exposure. Exposing fruit earlier in the season actually reduces risk of sunburn and lets grapes ripen more evenly. Cluster thinning is accomplished easier, picking grapes is easier (fruiting zone is between 40" and 50" from vineyard floor) and spray coverage is much more efficient with only a single narrow curtain of foliage.
Ease of establishing and re-establishing trunks and cordons. Because length of trunk and cordon is less than in high cordon systems, most cultivars can have established trunk and cordons in the first year. Also when replacing trunks because of cold damage this is done quickly.
What cultivars currently being raised in Nebraska are adaptable?
LaCrosse - has semi-upright growth. Medium+ vigor on most soil types.
Vignoles - has upright growth habit, could use VSP with low bilateral cordon in mid to southern Nebraska and possible head trained with fan and VSP in other locations with burying in the winter.
Frontenac - has been suggested for this cultivar only on medium vigor sites.
deChaunac - could be adapted to VSP only in medium vigor situations, deChaunac tends to be bushy in low to medium situations. This cultivar must be cluster thinned.
Chancellor - fairly upright growth, medium vigor works well on VSP.
Chamboucin - fairly upright growth, probably southern Nebraska only.
Prairie Star - semi-upright growth, low to medium vigor even on fertile sights.
Vidal - upright growth, might require much summer pruning because of excessive vigor.
Seyval - semi-upright, medium to medium+ vigor southern Nebraska only.
What are the components of a VSP?
Cordon Wire - depending on what level you choose for your cordons, this will be your first wire and should be no less than 12.5 gauge high tensile.
Height - 36" - 42" from vineyard floor
Fruit Zone Wire - This wire is not absolutely necessary, but is sometimes utilized because the spurs for short canes are not positioned vertically and need to be pulled into the fruiting zone. This problem is seen more in climates with severe cold damage, where viable buds are sometimes of a premium. 12.5 gauge high tensile wire should be used, height - 10" - 12" from cordon wire.
Catch wires - These are the wires that set the VSP system apart from most others. These wires are in sets with one wire having another wire parallel to it in a horizontal plane, usually only 3" - 4" apart, depending on what type of holding system is used on what type of line post. There are also manufacturers of line posts with built in clips or catches that are specifically made for VSP. There may be 2, 3 or more sets of catch wires depending on each specific cultivars and how difficult it is to retain within the wires. Smaller 14 gauge high tensile wire may be used here. Height - 1 set at top of trellis and others divided between there and fruit zone wire.
End Structures - There are many different end structures available, and some choices are determined by soil type or simply a growers preference for a system. Also if you are wishing to have a moveable set of wires (this is discussed in "how to manage you VSP") you might want to choose the H brace system or have some way to easily loosen the wires to move them.
How to manage your VSP
When to tuck or lift shoots - Early positioning before bloom may help some, but most bud initiation for fruitfulness occurs later in June or early July. Tucking and lifting very early may cause excessive shoot breakage especially on susceptible cultivars. With this in mind first tucking or lifting should be done shortly after fruit set and depending on cultivar and particular growing year, this may need to be done at least one more time.
Summer pruning or hedging - Depending on cultivar (inherent vigor and upright growth habit) and particular growing seasons, summer pruning and/or hedging may be required. The most inexpensive way to hedge or summer prune is with a machete (with a leg guard!) or with a hand operated manual type of hedger. These types of control are very labor intensive. A gas powered hand held hedger could increase productivity immensely with only a few hundred dollars in investment and can also be used for pre-pruning during dormant pruning. With highly vigorous cultivars and extremely vigorous growing conditions not only will it be necessary to trim off green shoots coming out of the top of the canopy, it might also be necessary to trim laterals that will encroach to the inside between the rows, if these are not removed you will negate the positive effects that you are trying to achieve with VSP. The most efficient method would be to use one of the automated type hedging and trimming devices available, some of these are available as multi-function machines, combining many vine operations from one machine.
Dormant Pruning - Dormant pruning can be done of course with only a single person, but much efficiency can be achieved with breaking up this project. By using inexperienced labor to pre-prune with a hedger and pull brush before final pruning, a 20% savings in man hours was achieved on four year old LaCrosse on a VSP.