If you've been to a wine tasting, you've probably heard the word "Terroir" used. What exactly is terroir and how does it affect your wine? Read on to find out!  

Terr-what now? Though this term is widely used within the wine community, few know its actual meaning. Of French origin (with a literal meaning of Soil, Region, or Land), terroir has come to encompass the complete environmental surroundings of the vine. This includes the climate, the soil, and the terrain. What effect does this have on the wine and how does it differ from region to region? Let’s delve into one aspect of terroir to see its effect on our wine: Climate.

Climate. The climate of a region is one of the most influential aspects of terroir. Because of climate, two different regions growing the same varietal can produce different results. For instance, a chardonnay from California can have extremely different characteristics from a Chardonnay made in France, and we have climate to thank for this.

Most sources will tell you climate is made up of two categories: Warm Climate and Cool Climate. The answer is actually slightly more complicated. Climate can encompass temperature, but also exposure to the elements such as wind, rain, and sun.

Tricky Temperatures.  Grapes grown in warmer regions, such as California and South Africa, see a gradual drop in temperature from the summer to the fall. Thus they have the chance to fully ripen, allowing for more natural sugars but less natural acidity. This leads to a higher amount of sugar consumption during the fermentation process which in turn produces higher alcohol content. This climate tends to produce fuller bodied wines well (think Cabernet and Syrah).

Cooler climates, i.e. Oregon and Germany, have a rapid drop in temperature which can stunt the ripening process. This produces wines with a more tart and acidic nature that tends to be lighter bodied (think Pinot Noir and Riesling).  The key is to avoid extremes.  A great growing climate is long moderately warm days with slightly cooler nights. 

Seems simple, but wait there’s more. You also have to factor in Micro-Climates. Micro-climates are everywhere. San Francisco is considered a micro-climate. It’s surrounded by warmer pockets but due to the winds and the fog exposure from the bay keeps a cooler temperature and produces, among other varietals, an excellent pinot. 

Let’s complicate it a little further. Each year can see warmer or cooler temperatures depending on the weather patterns, changing a wine’s nature from vintage to vintage.  A good portion of that has to do with the temperature that year. It may also have something to do with rainfall.

The Right Amount of Rain. Rain makes a huge difference.  Not enough rain and the vines won’t survive. With rain also comes cloud cover, which helps to moderate the temperature and control sun exposure. But as with all things, balance is crucial. Too much rain, especially right before harvest, and the drops seep into the vines, diluting the sugar levels. It can also cause problems such as millerandage, or immature grapes. Too much rainfall can also cause excess nitrogen in the soil and produce more foliage than fruit on the vines. 

Forget “Earth Wind and Fire”; Give me “Sun, Wind and Fog”! 

Without enough sunlight, sugar levels cannot properly develop in the grape. Sunlight also increases the tannin content. Too much sunlight however, especially around harvest, can create an imbalance in the sugar levels.

The right amount of fog and wind exposure helps to moderate temperatures and slow the ripening process (some wineries even use wind machines). Too much wind, however, can be damaging. And don’t even get me started on Humidity! Humidity can cause diseases, but have you ever heard of botrytis cinerea? Or maybe you’ve heard it referred to as “Noble Rot.”

That covers climate! Check out our blog on soil to learn the rest of the story on terroir!

Our previous article on Terroir dicussed how the surrounding temperature, rainfall, sun exposure and humidity have an effect on wine. But now that we know how the air permeates into the vine, lets dig a little deeper and talk about the ground the vines spring from.

The Secrets in the Soil. If great wine truly starts from the ground up, what kind of soil grows a great wine? The answer varies on the type of wine you’d like to produce.  Soil has the ability to produce a nice stable home life for the vines, based on a variety of factors. First, it needs to be consistent. It’s not uncommon for vineyards to consult with analysts to lay out the soil patterns on their land before mapping out their vines. Next, consider granulometry. It’s a big word for what it’s describing. Basically it’s the study of grain sizes in sedimentary rock. And it’s a large factor in our soil. Soil texture effects water runoff and infiltration. And then you have the organic properties of the soil to consider. Its materials determines it irradiance, or how much sun and heat will be reflected.

Now factor in your soil PH levels. If the soil is too nutrient rich it will overproduce grapevine vegetation and put less effort into the production of quality grapes. But too little nutrients and you’ll have a lack of foliage, leading to the possibility of scorched grapes. Is your head spinning with soil specifics yet? You could devote a lifetime to the study of soil and its effects on wine, but since we all can’t quit our day jobs and start a life of farming, let’s break it down into some of your most common soil types: 

1.       Sandy: No were not talking about the character from Grease. This type of soil has larger particles which mean less water retention. Roots can easily dig deep between the larger particles, and the lack of organic material means less threat of disease from humidity. Sandy soils tend to produce lighter wines.

2.       Clay: Nutrient rich with high water retention, due to its small granular structure. Smaller particles make it difficult for the vines to dig deep and can be more susceptible to diseases due to the water retention, but there’s less worry during seasons of drought. Clay is famous for producing some bold wines.

3.       Silt: The particle size lies in between the texture of soil and clay, meaning excellent water and heat retention, with some root difficulty. Tends to produce highly aromatic, less acidic wines.  

4.       Loam: A mixture of the first three types of soil, loam is considered highly fertile. Often it contains just the right balance of water retention and drainage for excellent production. However, as we’ve learned too fertile of a soil produces low quality wines. This soil type requires rigorous pruning regimens for a better production of wines.

Limestone in the Limelight. If there is a rock star of the soil world it is limestone.  Limestone can be considered the calcium rich Marsha to our metaphorical Brady Bunch. Dry weather? Limestone will retain the moisture you need. Too much rainfall? Limestone has excellent drainage. But beware, this golden child can cause iron deficiencies and higher acidity levels. Guess every rose has its thorn.

A Stressful Slope

Vines, like people, can rise from adversity. A betterquality grape is produced from stressing the vines. Want a dark, rich zinfandel? Plant it on a hillside. The water runoff and lack of nutrients means a more concentrated flavor, ending in a better wine. Ever see a winery boast about their “Hillside Select”? Now you know why. Higher altitudes usually mean rockier soils (and thus less nutrient rich) and cooler climates which allow the grape to ripen slowly. A hillside will usually produce a much lower yield, but the flavor concentration is worth the effort.

In the end, all Terroir is telling us is that vines are like people. You’ve got some stress and trauma, mixed in with a well of inner nutrients, and some outside care along the way to produce something amazing.