On an island in the Mediterranean, little green vines appear to erupt from black obsidian. 

As opposed to the vines growing on the Italian mainland a few hundred miles away, these vines will produce small berries concentrated with minerals and flavor. 

The resulting wines will be more savory than fruity – pepper in the nose, mineral notes, and a dash of salt.

These are volcanic wines, born of volcanic eruptions within written history (as opposed to geological history, a category that includes both Napa and Oregon’s Willamette Valley, neither of which produce wines that can be credibly compared to truly volcanic wines). 

But first, how many grapes are in a glass of wine? This week, resident expert Julien shares his favorite weird wine facts… like why we “toast”… what our Founding Fathers were drinking (and how you can get some)... why wine isn’t always vegan… and much more…

There are three predominant soil types in the vinicultural trades. If you enjoyed our Faugères rosé from last year’s French collection, you were tasting the fruits of a metamorphic “schist” soil. Our extreme-altitude malbecs, on the other hand, tend to come from a more sedimentary soil – with thin layers of clay over sand and chalk.

The third type is volcanic. It’s a wide category. Napa soils, as we mentioned earlier, are technically volcanic. Yet, the volcanos that formed them have long since died out. More recently formed are those of Santorini (from the caldera explosion that created the Atlantis myth about 3,800 years ago). More recent still are those of Sicily, where eruptions deposit a fresh layer of ash, obsidian, and rock every few decades.

Volcanic soils are a paradox. On the one hand, they appear to protect vines from pests and other threats (organic vineyards over 70 years old are common on Santorini, whereas vines on Europe’s mainland tend not to live past 25 years). On the other hand, they make it exceedingly difficult to survive. Volcanic soils retain little water, forcing vines to dig deep to find moisture and nutrients. They have so little organic content, they are, for all intents and purposes, barren.

Accordingly, volcanic soil vines produce small berries that ripen exceedingly slowly, sometimes only just getting there by harvest time (thus the savory rather than fruity notes). This is the opposite of what happens to extreme-altitude vines, where the berries are at peak ripeness by harvest time. 

Winemakers prize such a spartan upbringing because the resulting concentration boosts “aromatic depth.” There’s a lot to find in these wines, from the notes of flint and the salty finish common to most volcanic wines, to a whole slew of other aromas – peach, chamomile, tobacco, cherry – depending on what was present in the soil before the last eruption. Igneous (volcanic) rock is highly porous and will contain pockets of limestone and other minerals that got trapped in the lava flow or buried under the volcanic ash.

Volcanic soil also acts as a time capsule, preserving ancient varietals long since extinct in other areas. 

As long-time readers will know, most European vines are, in fact, American. After the phylloxera outbreak in the 19th century destroyed vast tracts of vines, European vignerons ripped out what remained and replanted with vines grafted onto American rootstocks, creating a new hybrid immune to the bug. 

The original European breeds survive only in a few isolated pockets of the world – most notably, the CalchaquíValley in Argentina, where old French vines produce extreme-altitude malbec at heights of 8,000 feet and more. 

In mainland Europe, so-called “ungrafted” or “pre-phylloxera” vines are rare. Yet, on Europe’s volcanic islands, small vineyards with thousand-year-old varietals still thrive. 

The indigenous assyrtiko grape of Santorini, for instance, which produces award-winning wines with 90+ ratings from Robert Parker, is said to be immune to phylloxera. Yet, this immunity has likely less to do with the plant itself and more to do with the soil. A combination of volcanic minerals and infertility makes it virtually impossible for bugs to gain a foothold (thus the predominance of organic wines from volcanic regions).   

The soil there comes from a 3,800-year-old explosion so extreme it may have both destroyed the nearby Minoan civilization (on the island of Crete) and created the legend of Atlantis (after vast tracts of Santorini sank into the sea).

More on that fascinating story in a future missive...

Until next time...

The Wine Explorer

Bonner Private Wine Partnership