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WineEast Commercial Establishment of High Tunnels Part II in a series about the usefulness of hoop houses in eastern North America By Richard Carey I n the previous article about growing highquality grapes in a covered environment (see "Beating Mother Nature at her Own Game" in the March 2013 issue of Wines & Vines), I presented evidence that winegrape quality was more than sufficient to examine the business/financial and physical aspects of growing grapes in a three-season tunnel. Can a high tunnel pay for itself? The simple answer to whether a high tunnel can pay for itself is that, in many environments, it may take up to three years—or it might take one day. Most growers use tunnels to mitigate or lessen some form of environmental upset that occurs at a vineyard location on too regular a basis, such as early or late frosts or too much rain. Grapegrowers should assess their vineyards from a financial standpoint: How often is there a spring frost event at the wrong time? How often is there a vineyard loss of 50% of the fruit for the year? If a grower is harvesting high-value crops with an average price of $2,000 or more per ton, the annual return per acre is $8,000 or more. A 50% loss means the grower turned over cash but did not make any money, with the intangible loss of a year of his or her life working to produce high-quality fruit. With grapes, a grower can't make up the difference the next year by increasing the vineyard's yield. There is also the possibility that the grower will lose not only the current year's profit but also have additional costs for rebuilding the vineyard for several years after the event. If a spring frost wipes out a season of production, averting one catastrophic loss could potentially pay for the tunnel. However, if the business includes both a vineyard and a winery, then the loss is magnified by the value these crops provide to the winery's bottom line. To the farmer the loss is $4,000 per acre, but for the winery side of the business, that loss represents about 100 cases of wine, or the equivalent of least a $24,000 drop in revenue. The more important that particular wine is to the WineEast HIGHLIGHTS: • unnels should be used for high-value T winegrapes to maximize their economic impact. Vines planted in a tunnel at Cramer Nursery in 2010 filled out the trellis by June 2012. The row on the left is Cabernet Sauvignon; Petit Verdot is on the right. winery's bottom line, the more significantly that number can increase. Another major benefit of the tunnel is an increased yield of equal or better quality fruit. In the previous article, I explained there was nearly a doubling of the yield for grapes grown in the tunnel as opposed to those grown outside. With little increase in farming cost, the per-acre yield should easily double to $16,000 per acre. The tunnel environment has several other advantages. For example, we all know the soil is a fundamental factor in the growing of high-quality grapes. One of the major issues in all commercial farming is soil compaction due to heavy equipment accessing the fields. The tunnel structure provides an excellent opportunity to modify farming practices to mitigate compaction to nearly negligible levels. In addition, the tunnel can be viewed as a containment vessel. If your vineyard is in a location where surrounding property owners are worried about spray drift, the tunnel can • t may take up to four years to pay for I the cost of a tunnel—or one day. • grapegrower can double the yield of A equal or better quality fruit. provide an excellent physical barrier. Just roll down the sides, shut the door and spray. Other secondary reasons for purchasing tunnels will become evident as we look at the various aspects of designing and installing a tunnel system. Tunnel design factors Several considerations must be evaluated when choosing a tunnel type. Existing terrain is certainly important, but the most important consideration is working height. It is possible to work inside a tunnel with mechanized equipment, and with the exception of the largest pieces of equipment, just about all types of grapegrowing devices can be used in a tunnel. The most important limitation is how to work the rows next to the pole-line. The solution is to leave more row edge to get vertical height (see "Basic Hoop Layout" on page 90.) Win es & Vi n es A PRI L 20 13 87