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W i n e s & V i n e s A U G U s T 2 0 1 4 79 B e it too hot, too cold, too wet or too dry, many locations are not ideal for growing grapes and making wine. Yet people are growing grapes and making wine in all 50 states, whether they face difficult environments or not. Of course, even the best places to grow grapes have years that are challenging. On June 27, the final sym- posium at the 65th national conference of the American Society for Enology and Viti- culture in Austin, Texas, examined different aspects of growing grapes and making wine in challenging environments. Sara Spayd, professor in the Department of Horticultural Science at North Carolina State University, introduced the symposium by saying, "We are not talking about challenging environments within the winery, so the program's focus will be on some of the viticultural and enological issues arising from environmental challenges." In the vineyard The major problems with growing grapes are related to sunlight, temperature and water. Growers can use various management op- tions to address those problems, including site selection, vineyard design and viticul- tural practices within a growing season. Ed Hellman, a professor of viticulture at Texas Tech University who has a joint appoint- ment with Texas Cooperative Extension, examined the different challenges facing growers in detail. If the problem is insuf- ficient sunlight, for example, the grower will need to take that into consideration when planning the design of the vineyard. Slopes should be south-facing, rows planted in a north-south orientation, and the vine spacing and training system both should be appro- priate for the anticipated vigor of the vines to be planted on the site. The fruit zone may need to be up high and ex- posed, and in-season viticultural practices may include shoot po- sitioning, basal leaf removal, hedging and reflective mulches. On the other hand, if the challenge is excessive sunlight (leading to excessive heat), or a heat wave with temperatures at 104° F or higher for an extended period, the grapes may have a lower anthocyanin concentration, reduced malate and total phenolics, "cooked fruit" flavors and sun- burn due to excess light and heat. If the potential for excessive heat or sunlight is known before the vineyard is planted, the grower can find a site with an east or north slope aspect, plant cultivars that are more tolerant of heat, orient rows in a northeast- southwest direction to reduce solar heating, use a trellis system with wider cross-arms on VSP catch wires to encourage partial shading of the fruit zone, and consider using sprawl or high-cordon train- ing with no shoot positioning. During the grow- ing season, grow- ers can prune to a higher shoot den- sity (five shoots per foot), shoot position only on the shaded side, use a modified VSP system with wider cross-arms, and plant a cover crop, stubble or mulch to avoid the re-radiation of solar heat. Other within-season practices may include delaying véraison so the fruit will mature when the temperatures are cooler as well as increasing the crop load. Cooler climates with insufficient heat can lead to grapes with incomplete fruit matu- rity. Consequently, it's important for grow- ers to select cultivars that mature early and require fewer heat units to ripen. Vineyards should be south-facing with north-south row orientation (similar to the insufficient sunlight vineyards) and situated at lower el- evations. Training systems can have narrow canopies, a high fruit zone (such as sprawl or GDC), or a low VSP can be used to take advantage of reflected ground heat while recognizing that there will be more risk of frost. Within-season practices may include shoot positioning and basal leaf removal to increase cluster light exposure, and the vineyard floor may be clean cultivated. Regions with excessive cold weather pres- ent challenges for vines in the dormant sea- son as well as the growing season. Very low temperatures can lead to trunk, cordon and bud damage resulting in reduced, inconsis- tent yield and asynchronous fruit ripening. Growers should avoid south- and southwest- facing slopes, as they often warm earlier in the spring and may be more prone to WineEast Wine East HIGHLIGHTS • The Association for enology and Viticulture held a Winemaking for Challenging environments symposium during its 2014 national meeting in June. • speakers discussed vineyard management techniques to compensate for less than ideal grapegrowing conditions including temperature, precipitation and vineyard orientation. • A follow-up article will discuss cellar techniques intended to improve wine quality for grapes grown in challenging vintages and environments. Surviving Challenging Environments ASEV conference addresses vineyard management tactics for difficult locations By Linda Jones McKee Basal leaf removal can increase cluster light exposure in cooler climates with insufficient heat. ED HELLMAN