Why Does Vineyard Site Location Matter?

At Philip Carter we have three vineyards; Bigfoot in Warrenton, Philip Carter Winery (PCW) in Hume, and Strother Family Vineyard (SFV) in Delaplane.   Each is situated at a unique location.  While you are all familiar with the vineyard at PCW, the strongest vineyard that we have is our youngest, SFV.  It exemplifies some aspects of site location that I am about to go over.  When you see Tony or me in the Tasting Room, feel free to ask us about this great site and what exciting developments it is bringing to Philip Carter Winery.

Let me preface this by saying that site location is a complex topic with myriad factors going in to having the right location for a vineyard, but in a perfect world, we would take all of these elements into account when selecting a site.  Vineyard site selection is probably the most important decision in the life of a vineyard. It takes several years to develop a vineyard and produce a regular crop of grapes.  A vineyard will remain productive for decades.  Although grapevines can grow in many places, successful cultivation for quality wine production is limited to sites where specific conditions are met and rigorous management practices conducted. Some of the primary factors affecting vines are as follows:

  • Physical Environment (e.g., elevation, latitude, slope, aspect, soil type);
  • Natural Phenomena (e.g., climate, seasonal variations, weather & hazards);
  • Viticulture and Vineyard Management (e.g., layout of vineyard, grape varieties and rootstocks, infrastructure (irrigation, wind machines)).

This is a lengthy topic and for today’s conversation I am going to address some of the physical aspects that you must evaluate when selecting a vineyard site.  Be warned, that this discussion is going to get a little technical.

Elevation

Elevation influences the minimum and maximum temperatures in a vineyard. Lower elevations are preferable at high latitudes, and higher elevations are more desirable at lower latitudes. On average, the temperature falls 1.1 degrees F per 330 feet (0.61°C/100 m) of elevation, which means the growing season will be shorter increasing the possibility of frost at higher elevations.

 

Relative Elevation

Poor relative elevation can significantly reduce the quality of an otherwise good site; such is the case with vineyards located within valleys.  Although the vineyard may fall within the acceptable absolute elevation range, because of its location at the lowest point at an otherwise good elevation, it may be prone to spring and fall frosts.  It is better if the vineyard is located at an elevation referred to as the “thermal belt.” The thermal belt is a mountainside zone where frost or freezing temperatures are less likely to occur than they are at either higher or lower elevations.

 

Latitude

Grapevines are temperate-climate plants; the major viticulture regions of the world are concentrated between the latitudes of 30 and 50 degrees.  In this zone the relatively large diurnal (daytime vs. nighttime) temperature range is optimal to produce the combination of sugar and acid levels that enable grapes to be made into quality wine.

 

Slope

The slope of a site refers to the degree of inclination of the land expressed as a percentage.  For example, a 5-foot fall over a 100-foot horizontal distance would be a 5 percent slope. The ideal site for grapevines is on gently sloping land that allows cold air to drain into lower areas.  This reduces the risk of frost injury and cold winter temperatures.  Further, good air drainage promotes faster drying canopies, which reduces the frequency of disease.

 

Aspect

A vineyard’s aspect refers to the direction that the slope faces (e.g., east, southeast, etc.). Aspect affects the angle that the sunlight hits the vineyard and heat balance.  Aspect is more important in higher latitudes where radiation is weaker, due to the angle of the sun, and light interception may be limiting to growth.

 

  • Southern-facing Aspects

Vineyards with southern aspects (for the Northern Hemisphere) warm earlier in the spring and the vines may undergo bud break earlier than vineyards with northern aspects. The early bud break is desirable in locations that do not have a danger of spring frost because it translates into earlier bloom and harvest of the fruit.

 

  • Western-facing Aspects

Western-facing slopes are a popular choice for late-maturing varieties, such as Cabernet Sauvignon, promoting fruit ripening in the waning heat and daylight of fall.

 

  • Eastern-facing Aspects

Eastern-facing aspects receive the first of the morning radiation, warming canopy and soil temperatures fastest when temperatures are generally at their lowest and most limiting.

 

  • Northern-facing Aspects

In cool climates where summers are cool and growing degree-days are low, northern slopes (for the Northern Hemisphere) should be avoided and southern aspects (S, SE, and SW) are preferred to allow maximum heat accumulation on that site to grow and ripen grapes.

Soil

Soil supports vine root structure and influences the amount of minerals and nutrients available to the vine.  The ideal soil condition is a layer of thin topsoil and subsoil that retains water but also has good drainage so that the roots do not become overly saturated.  The ability of the soil to retain heat and/or reflect it back up to the vine is also an important consideration that affects the ripening of the grapes.  Some of the more common soils that we see in Virginia are as follows:

  • Clay

Sedimentary rock based soil that has good water retention ability but poor drainage. The soil is often very cool and high in acidity. The Right Bank of Bordeaux is dominated by clay-based soils.

 

  • Granite

Composed of 40-60% quartz, 30-40% Orthoclase and various amounts of hornblende, mica, and other minerals. This soil warms quickly and retains heat well. The soil’s high level of acidity works to minimize the acid levels in the grapes.

 

  • Loam

Warm, soft, fertile soil composed of roughly equal amounts of silt, sand and clay. It is typically too fertile for high quality wines that need to limit yields in order to concentrate flavors.

 

  • Shale

Fine grain sedimentary based soil that can turn into slate when under pressure. The soil is moderately fertile and retains heat well.

I have just hit you with some very technical information, my suggestion is that the next time you are at a winery with an attendant vineyard, take some of these factors into account and evaluate the site.  Then ask questions during your tasting or with knowledgeable members of the winery staff.  You will learn more and it can be fun for the staff to have an in-depth conversation.   Personally, I love to geek about wine and have great conversations with others who are interested in our industry.

The History of Port

Port was developed in the early 1700s because of a trade agreement between England and Portugal.  England and France had been in a mercantile war that oftentimes broke into open warfare and of course, England is too far north to really grow and ripen grapes (though they’ve been exploring Sparkling wines of late).  Therefore, the English were looking for other places where they could possibly find wine, and one of those places was Portugal.  They concluded a treaty in 1703 that reduced the duties on English woolen goods, which would then be shipped to Portugal, and reduced the duty on Portuguese wine, which would then be brought back to England.

Well, this all sounded well and good except that the Portuguese wine didn’t taste the same as the French wine, and the English consumers didn’t accept it.  Therefore, the individuals who were involved in the trade had to come up with a new type of wine, and they were the ones who developed what we know today as Port.  They arrested fermentation when the wine was still quite sweet and added alcohol until the wine roughly reached 18% alcohol.

Philip Carter’s Port Style Wine – ‘1762’

In the spirit of this tradition, our port style wine is made from 100% Chambourcin grapes from the 2015 harvest.   It has been aged in Bourbon Whiskey barrels from the A. Smith Bowman distillery for 38 months.  The wine is fortified shortly after fermentation with high alcohol grape brandy and is both unfiltered and unfined.  This wine shows an intense deep red color with orange hues from longer barrel aging.  On the palate, it is full of ripe red fruit flavors, rich dark chocolate, and a touch of bourbon leading to a long-lasting finish.  It is 6.3% residual sugar and 18.8% alcohol.

Food Pairing Notes

This port pairs well with both mild goat cheese as well as aromatic blue cheese. A fine cigar is also a worthy companion for this wine.

Vineyard Activity during the Depths of Winter

At this time of year we are frequently asked, what if anything is going on at Philip Carter Winery? While the production work has slowed following the conclusion of harvest, it is one of the most important times of year for our vineyard management program.

The main purpose of vineyard management is to achieve a maximum yield of fruit, at the desired quality level. One of the greatest influences on both yield and quality is winter pruning. Winter pruning involves the removal of up to 90% of the previous season’s vine growth. The overall goal of winter pruning is to prepare the vines for the upcoming growing season. This pruning helps to construct the location and general development of the canopy. A properly constructed canopy has great influence on overall grape yield, health, and development.

This highly influential pruning is normally conducted during the winter months, while the vines are dormant. In the fall, the vines begin moving complex minerals and nutrients via the vascular system from the leaves, down into the permanent wood (roots, trunk, and cordons). Pruning too early in the season can disrupt this nutrient transfer, leaving the vines deficient for the upcoming growing season. Pruning too late can sometimes lead to a delayed bud-break, which in turn can affect the entire growing season. In addition, pruning while the vines are dormant and absent of foliage allows for easier wood selection and cane tying.

The first round of winter pruning removes the majority of the cane (the previous season’s growth) to allow for a more precise bud selection at the final pruning pass.

Pruning removes buds, via cane removal, that would otherwise become new shoots and bear fruit the following season. By removing buds, growth is concentrated into the remaining buds, and eventually, canopy and fruit development. Before winter pruning, a single vine can have well over 100 buds. On average, a single vine is pruned down to 30-36 buds per vine.

Pruning either too much or too little can lead to an unbalanced vine and grape development. Pruning the vines too much means more buds were removed than necessary and the growth from those remaining buds might not provide enough nutrients and minerals to fully ripen the fruit. During dormancy, precious nutrients and minerals are stored in all woody parts of the vines, and the more woody material removed, the fewer nutrients and minerals available for the upcoming growing season. Not pruning the vines enough means too many buds were left on the spurs, which will result in an excess of vegetative growth, leading to uneven fruit development.

Selecting how many buds to leave per spur depends on many different factors. Usually, the younger a vine the fewer buds left per spur. As the vine matures, more buds are left per spur until vine and grape development are at an achieved balanced state. If vines sustain cold damage over the winter, more buds may need to be left per spur to achieve proper vine and grape development.

Winter pruning should be seen as just the first step in a growing season towards achieving vine balance and optimum grape development. When properly pruned, shoot vigor can be controlled permitting the vine to fully ripen its fruit to the desired yield. Equally important to consistently ripening fruit from one year to the next is the overall long-term health of the vines.

At PCW, we have three distinct vineyard locations, Vineyards at Hume, Strother Family Vineyards in Delaplane, and Bigfoot Vineyards in Warrenton. Three unique vineyard sites across the northern Piedmont totaling 20 acres of vineyards.

Of our three locations, the Strother Family Vineyards offers one of the preeminent vineyard sites in the Mid-Atlantic region of the United States. Its southeast aspect and dramatic slopes are perfectly positioned at a 1,050’ altitude. The soils are a silty clay loam with a complex residuum mix of weathered granite and gneiss, and are classified by the U.S. Department of Agriculture as being of statewide importance. There is a sense of place to SFV and its terroir produces exceptionally delicate wines with beautiful minerality that are both expressive and reflective of the Piedmont of Virginia region. At this site, we grow Chardonnay, Cabernet Franc, and Petit Manseng.

Definitions
Buds – One or more embryonic shoots protected in a series of modified leaves called bud scales.
Bud Break – When buds begin to swell and grow.
Cane – The vine shoot from the period it matures and lignifies (turns brown and woody) until the end of the second year of growth.
Canopy – The foliage cover of the vine.
Compound-bud – The mature axillary bud that survives the winter; typically possessing three immature buds in differing states of development.
Cordon – An arm or trunk extension positioned horizontally or at an angle to the axis of the trunk.
Spur – A short cane possessing the desired bud count.
Trunk – The vertical wood stem of a vine up to the origin of the branches.
Vitis vinifera – The primary grape species cultivated and used as a source of wine, table grapes, and raisin grapes.
Yield – The fruit crop per area planted.