Istria: Wine Across Borders

“My family has lived in the same house for over a century, yet the last four generations have had four different passports,” explains Croatian winemaker Ivica Matošević. He lives in the heart of Istria, the largest peninsula in the Adriatic and a region that has often been tied up in a political tug-of-war. Istria has been ruled by the Venetian Republic, the Habsburg monarchy, Napoleon, the Austrian empire, Italy, and Yugoslavia. Today, nearly 90% of the zone falls into Croatia (which itself joined the EU in 2013), while smaller parts of it lie in Slovenia, and there is a tiny portion in Italy close to Trieste. This may explain why people in this area see themselves as Istrian first and foremost, attached to fixed geography rather than changing political identity. Boštjan Zidar, the chief winemaker at Vinakoper in Slovenia, confirms this, saying, “Every Istrian feels first that Istria is home. Then you can talk about Croatian, Slovenian, and Italian people. Politicians make borders, which make barriers, but the people who live here—their friendships, love, and wine—can always win over these borders.” This also may be why Istrian identity allows better cooperation between winemakers across national borders than is common in this part of Europe. This regional update will focus on Istria’s geography, grapes, viticulture, and winemaking, considering what is shared between Croatia and Slovenia, and what is different.


Istria is a beautiful region of rolling hills, terraced vineyards, olive groves, and medieval hilltop villages. It’s surrounded by the Adriatic on three sides, with the Julian Alps to the north. The climate is sub-Mediterranean to Mediterranean, with warm summers and mild winters, so snow and winter frost damage are rare. The region tends to be breezy, with relatively low fungal pressure thanks to the winds. The cold dry bura wind (burja in Slovenian) from the north frequently reaches 120 kilometers per hour—and has been recorded at 200 kilometers per hour, blowing cars off the road. The coastal areas are also moderated by the mild maestral sea breeze in summer and by the jugo, which is a warm, moist wind from the sea that often brings rain. Rainfall can be as low as 600 millimeters, ranging up to around 1,300 millimeters, though drought is an increasing problem, and irrigation is still rare. Vineyard altitude ranges from around sea level to about 400 meters.

The peninsula is largely underlaid with karst bedrock, though topsoil varies. The Croatian part of Istria is divided into White Istria to the north and northeast, where the topsoil is thin and typically rocky, white, and carbonate rich. Further south and inland is the central zone of Gray Istria, where flysch with marl and sand appears, as well as humus-rich deposits of black soil. Flysch is also typical of the Slovenian part of Istria, where such soils are called opoka. Toward the coast and in lower-lying western areas, there are distinctive, rich, rusty red terra rossa (or crljenica) soils, giving this region the name of Red Istria.


Croatian wine law was recently rewritten to divide the country into four major wine regions, of which Istria and Kvarner together form one of the four (the others are Dalmatia, Croatian Uplands, and Slavonia and Croatian Danube). As of 2021, Croatia includes approximately 18,500 hectares of vineyards, and within that, the county of Istria has 2,900 hectares under vine (around 10% of its area pre-phylloxera). There are a further 200 hectares in the Kvarner county, which covers the islands in Kvarner Bay to the east of Istria itself. (Here, the lightly floral, mineral Žlahtina grape is most important, with a small movement to revive the rare local Sansigot, which yields light red wines.) Within Croatian Istria, there are around 250 producers, of which 111 are members of Vinistra, the regional organization representing winegrowers and producers. Vinistra is responsible for political lobbying on behalf of the industry as well as running a wine competition and annual wine fair. Around 10 million bottles of wine are produced annually in Istria; the largest producer, Vina Laguna, makes nearly half of this total, at 4.5 million bottles.

On the Slovenian side of the border, Slovenian Istria, or Slovenska Istra, is one of four wine districts in Slovenia’s western Primorska region (along with Brda, Vipava Valley, and Kras). It’s the most southerly part of Slovenia, the warmest zone, and the only area in Slovenia with sea access (Slovenia has a very short coastline, at just 47 kilometers, compared with Croatian Istria’s 539 kilometers). The region has 1,838 hectares of vines as of 2022, with 203 winemakers who bottle wine, including 11 companies and the rest as small producers. There’s one large private producer, Vinakoper, that owns 570 hectares. Producers and growers are represented by the Slovenian Istria Winegrowers’ Association (Društvo Vinogradnikov Slovenske Istre), headed by one of Slovenia’s most high-profile women winemakers, Ingrid Mahnič. She has organized a Malvasia festival in Portorož for 24 years.

The Slovenian Istria Winegrowers’ Association and Vinistra have a good relationship and invite each other to events. As Mahnič explains, “When presenting wines to foreigners, I always emphasize that I will talk about Istrian wines and Istria, even though we are in Slovenia.” Looking to Istria’s future, she says, “I believe that we are not going to increase the area of vineyards much, but we can do a lot to promote excellent Istrian wines and thus also contribute to the recognition of Istria as a wine destination.”


Malvazija in Croatian Istria

Croatian Istria is dominated by Malvasia Istriana, or Malvazija Istarska, which accounts for 1,583 hectares (55% of the region’s plantings in 2021). The grape is the second most planted variety in Croatia after Graševina, though fewer than six hectares planted are outside the Istrian region. There are many grapes in the wine world called Malvasia, but this one doesn’t appear to be closely related to any others. The local spelling of Malvazija Istarska, complete with the letter z, highlights its distinctiveness. The grape has a long history in its home region, and documentary evidence goes back to 1385, when a physician called Bartolo requested a permit to buy 5.5 liters of Malvasia wine. There’s a Greek theory of its origin linked to the port of Monemvasia, called Malvasia in Italian, where wine known as Malvasia was traded in the Venetian era. Genetic analysis, however, doesn’t support this theory and shows Malvazija Istarska as unrelated to Greek grapes.

Winemaking and Viticultural Approaches

Malvazija Istarska, like so many varieties in this part of the world, was treated as a volume workhorse in the previous era. According to Gianfranco Kozlović, “Originally, it was terrible wine.” Kozlović was arguably the winemaker who kick-started the new approach to quality with this grape in the early 1990s, when he was the first to introduce temperature control and to install a modern winery in Istria. Thanks to Kozlović and several other visionary winemakers, it has become clear that Malvazija Istarska is capable of producing high-quality, ageworthy wines and is able to reflect a place, or terroir. Most consumers, however, probably have no idea of this potential, as the vast majority of the wine is vinified in stainless steel at a controlled temperature for simple, fresh summer drinking. For most wineries, this is the core of their production, typically at least 70%. These wines are quick to make, quick to sell, and perfect for the many tourists enjoying the Adriatic coastline. Usually, these wines will be consumed within 12 to 18 months of harvest.

But Malvazija Istarska offers many options to the ambitious winemaker. It’s a grape suited to skin contact, more typically cold maceration before fermentation, but some producers also use extended maceration (weeks or even months) along with alcoholic fermentation to make genuinely orange wine styles, sometimes in amphora. These techniques can produce wines with wonderful texture and mouthfeel, and with layers of complexity. The grape can also work well with fermentation and aging in barrels. Options in use include large and small oak, acacia, and even mulberry. In fact, Malvazija often has a gently honeyed character that works particularly well with the fragrance of acacia barrels (though only four or five producers use acacia in practice). It’s also a grape that can work well in blends, and there are successful examples with Chardonnay in particular. In terms of terroir, the red soils give the most structured versions and the white soils the most fragrant, while black soils seem to emphasize the fruitiness of the grape, with gray soils somewhere in between. Finally, ageability can add to the picture of credibility for this grape—even if most consumers only age wines in the boot of the car. A recent vertical tasting of Matošević’s entry-point Alba Malvazija, which was made with the intention of selling it as a young wine, showed that the 2002 was still in very good shape at the two-decade mark.

Various factors have contributed to these changes in quality. Kozlović points to “better vineyard management, meticulous cellar techniques, better definition of the terroir, and most of all, better understanding of the . . . soul of Malvazija Istarska.” The consultant Milan Budinski, who works with Vina Laguna, Veralda, and Bastiàn, mentions that clonal selection has also improved; there are now around eight clones commercially available. He highlights VCR 4 as the first to be selected, in 2005, and the most common, but he thinks it is better for richer, more phenolic styles, and particularly for skin contact wines. He finds that FVG 121 produces finer, fresher styles, with good natural acidity—and acidity can be an issue with Malvazija. The grape is naturally moderate in total acidity, and wines are often acidified. Matošević adds that there’s a need to fine-tune the clonal offer to match clones more closely to the distinct soil types in Istria, and to consider drought tolerance, so this is still work that is in progress.

Malvazija in Slovenian Istria

In Slovenian Istria, Malvazija accounts for 622 hectares, which is 34% of plantings, second in the region after Refošk. Stylistically, it tends to produce wines that are firmer and less floral than those of Croatian Istria, though still with high quality potential. Rok Jamnik, the winemaker at Vinakoper, comments that the major differences, compared with Croatian examples, are probably the result of soils (this region is largely opoka). There may be clonal differences, too. Most clones grown on the Slovenian side are SI 37, VCR 4, VCR 26, VCR 113, VCR 114, and VCR 115. Jamnik notes that the latter three have been most planted recently. He explains, “[They] give more citrusy notes, good structure, and nice acidity, which is more and more important because of the climate.” There are also good Malvazija wines made in Slovenia outside Istria, as the grape has spread into the regions of Brda and Vipava Valley. These wines are often simply labeled Malvazija.

Teran and Refošk

Teran in Croatian Istria

The sometimes controversial grape now officially identified as Terrano but called Teran in Istria is probably Italian in origin. One parent has been identified: Refosco Nostrano. Just to confuse matters, there’s also a Refosco dal Peduncolo Rosso grown in the region, which does not appear to be directly related to Teran but is believed by producers to be close and certainly looks morphologically similar.

On the Slovenian side of the border, the main red grape is Refošk, and it seems some of this may be genetically identical to Teran—and, importantly, is not related to Refosco dal Peduncolo Rosso either. Controversy arose in 2016, as there is a wine called Kraški Teran produced in Slovenia from grapes known as Refošk. Slovenia protected this wine under EU law simply as Teran and insisted that Croatia could no longer use this grape name. Croatian producers objected, insisting that grape names cannot be protected under EU law, and that “their” grape, under that same name, had a long history, dating back to the 14th century and covering as much as 90% of Istrian vineyards in the 19th century. In the end, the court of arbitration in The Hague ruled that Croatian winemakers can use Teran if Croatian Istria or Hrvatska Istra also appears on the label.

Winemaking and Viticultural Approaches

Phrases like “wild beast,” “brutal tannins,” and “green acidity” are often used by winemakers to describe how hard it is to work with Teran and get it ripe. Its nature, says Marko Krstačić, winemaker at Medea Winery, is “high acid, low alcohol, and metallic earthiness, with notably tannic pips.”

Winemaker Moreno Coronica was a crucial figure in changing the fortunes of this grape. He has compared it with Nebbiolo in terms of cluster shape, size, and color; thin skin; and susceptibility to botrytis. He explained that his moment of revelation came when he saw green harvesting in Piedmont. His father didn’t speak to him for 10 days after he did the first green harvest back in Croatia. Teran is naturally a vigorous, high-yielding grape, and Coronica undertakes leaf removal, with grass in alternate rows to reduce vigor. He also likes to wait for 25% dehydrated grapes before picking.

Nikola Benvenuti of Benvenuti Winery agrees that low yields are essential. Some years, he drops as much as 70% of the Teran crop to get the remainder ripe and may even cut off part of the bunches. Gianfranco Kozlović agrees that working with Teran is complicated. He says, “We still have more to do on fine-tuning of the grape. . . . We are now only halfway.”

Winemaker Milan Budinski, however, is not keen on Teran. He says it’s fussy about site and has a very long flowering period with uneven budbreak, adding that Teran must be harvested under six tonnes to the hectare for quality. He feels this low yield does not play well in terms of the organic sustainability story, with Teran taking up more land to produce a commercial crop than other grapes. He prefers Refosco dal Peduncolo Rosso, which he insists is easier to grow and produces similar quality at 10 tonnes to the hectare.

Winemaking approaches for Teran are varied. Cold-soaking and removal of pips is preferred by wineries like Medea, which is attempting to make lighter, fruit-forward versions, while other winemakers go the opposite way, with very long skin contact, then oak aging to allow tannins to achieve greater complexity.

Refošk in Slovenian Istria

The grape grown as Refošk in Slovenia may or may not turn out to be genetically identical to Teran. It certainly is in some cases, though overall the picture is far from clear. Boštjan Zidar explains that he must order Teran from an Italian nursery to get the vines he wants to grow as Refošk, whereas Slovenian nurseries supply material under the name Refošk—the same Refošk that goes to Kras for Kraški Teran. Zidar adds that there are not significant differences between the two. Refošk accounts for 788 hectares of Slovenian Istria’s 1,838 hectares of plantings and is the most important grape in the region.

Stylistically, Refošk is distinctive in Slovenia, producing inky, purple-toned wines with firm acidity. The wines tend to be linear rather than broad in structure and may have tannins on the austere side, though there is good potential for longevity. As the biggest producer in the region, Vinakoper has been working hard to make the wine more drinkable and appealing to a wider audience. Winemaker Rok Jamnik says, “We are playing with oak that gives sweet flavors, which can balance acidity. At the same time, we are providing a lot of oxygen to remove reactive tannins. During maceration, we are removing seeds, because they can still be greenish and give harsh sensations in the mouth. For extraction from the skin, we are using cap wetting but are trying to introduce different maceration techniques to achieve [a] more fruity and softer character.” Full malolactic fermentation is essential in modern versions (this was not always used in the past), as the variety is typically high in malic acid.

Other Grapes and Styles of Note

Muškat Momjanski is a PDO for Muscat Blanc à Petits Grains grown around the small town of Momjan, in Croatia. These wines are usually aromatic and semidry to semisweet. Muškat Ruža is a tricky, pink-skinned Muscat with female flowers—it needs a cross-pollinator (the Poletti winery uses Teran) and is usually made as a rosé but sometimes as a light red. Sparkling wines are trendy, of course, here as everywhere. Both tank-fermented and traditional-method examples can be found, though so far it seems that using some Pinot Noir or Chardonnay is helpful, as Malvazija on its own lacks the acidity for top sparkling wine. There are also a handful of genuinely sweet wines made from passito Malvazija or Muscat (made from dried grapes, as this is not a region for noble rot).

On the red side, there’s something special about this Adriatic coastline for Merlot, which does especially well in Istria and northward as far as Slovenia’s Vipava Valley. According to Ivica Matošević, “We can play in the champion’s league with Merlot.” No one is totally sure why, but the combination of sunny Mediterranean climate and moderate nighttime temperatures, thanks to Alpine winds, seems to be important. This allows slow but full ripening while preserving freshness, as Merlot can so easily be heavy and flabby in a warm climate. Merlot works well both in varietal wines and in blends—for instance, to soften and fill out Teran. And, of course, there are examples of the main international reds and whites, though these are rarely a winery’s prime focus. Most prefer to talk about local grapes.

On the Slovenian side of the border, Istria is the only part of the country that can reliably ripen Cabernet Sauvignon, the region’s third most planted grape, at 90 hectares. There have recently been some impressive efforts with Syrah, and Rumeni Muškat (Yellow Muscat) and Merlot are also significant.

General Viticultural Issues

Global warming has clearly hit Istria, making hot summers and drought more frequent concerns. Thirty years ago, defoliation in red vines was essential for ripening, whereas now leaves are often left on to avoid sunburn. Winemakers including Matošević and Kozlović are working on an irrigation project with the local university as a model to improve Istrian wine quality in view of climate change. Drones are used to assess vines and help growers irrigate the minimum necessary to avoid excessive stress—treading the tightrope between just enough stress and not too much. Matošević says he can even opt to irrigate just the outer row on a terrace. Training in the region is typically Guyot on wires to manage vigor. Because the region is breezy, there is relatively low disease pressure, so many producers are moving toward sustainable or organic practices (though relatively few are certified organic). Esca and flavescence dorée, however, are present.

Labor challenges are a topic for many producers in Istria, as in much of the world. It used to be the case that people would work the tourism season and then switch to picking grapes. But the tourism season has extended later into the year, and the harvest has come earlier. Some producers reportedly bring in workers from Nepal, while others say they can manage with local workers by treating them well, involving them in projects, and paying them properly. Machine harvesting is becoming more common, though this is only an option for wineries with larger, flatter vineyards. Marko Rossi, the owner of Rossi Winery, explains that machine harvesting has the benefits of reducing the number of workers required and allowing them to pick during the cool nights.

The knock-on effects of fragmentation of land and difficulties with land restitution have continued. For instance, Ivan Damjanić, in Croatian Istria, points out that his family lost 40 out of 45 hectares through nationalization, and the remaining 5 hectares was divided between four brothers. This sort of fragmentation has made it hard for wineries to put together plots of a good commercial size. This applies in Slovenia, too, where there are 1,882 growers for 1,838 hectares of vines.


Tourism is a mixed blessing for Istria, with much of its wine—especially fresh Malvazija sold within 18 months of the harvest—sold to visitors, providing fast turnover and a quick cash return. Restaurants will even try and return unsold wine at the end of the season. During the Covid-19 pandemic, tourism has continued to be successful in Istria, because the region is near enough to Germany, Austria, and Poland that tourists can drive—unlike regions further south that traditionally rely on cruise ships and flights for tourism. This creates little incentive for most wineries to export, and those that do tend to export to neighbors in central Europe, where there’s a shared history and understanding of grapes and wine styles. As a result, there are few Istrian wines from either Slovenia or Croatia in Western markets.


In today’s thirst for authenticity in wine, there is plenty to explore in the region of Istria on both sides of the border, but, to get the full picture, a visit to the area is necessary. The industry has gone through several waves and continues to change and adapt. It has moved on from the volume era that spanned the 1950s to the 1980s, and today it is much more focused on quality. The first-generation private producers in the new era tended to learn on the job, whereas the next generation of young winemakers has often studied at university, many at Poreč, in Istria, bringing a new professional approach to winemaking and a better understanding of what this exciting region can offer.

Recent political developments will also help bring greater unity to the region of Istria, and the often-long queues at the Slovenia-Croatia border in Istria will soon disappear. In 2023, Croatia will become part of Europe’s Schengen zone, which allows passport-free travel across national borders. At the same time, it will adopt the euro as currency (Slovenia has used the euro since 2007), both big steps in helping Istria feel more like a single region.

Special thanks to Vinistra for the Croatia data and to Boštjan Zidar of Vinakoper for the Slovenia data.

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