Assyrtiko Santorini: Volcanic Vines, Basket Training and Island Wine

Assyrtiko is the white grape at the heart of Santorini’s wine: a variety native to the island that keeps its sharp, fresh acidity even in a hot, dry climate, and that grows in volcanic soil so poor and sandy that the vine pest phylloxera has never been able to take hold. On Santorini it is traditionally trained low to the ground, its shoots woven into round baskets called kouloura that protect the grapes from the wind and sun. The result is one of the most distinctive farming landscapes in the Mediterranean, and a wine that tells you a great deal about the island it comes from. On our Santorini, Crete, Rhodes and Cyprus tour we visit a winery and its basket-trained vineyards on the afternoon of Day 4.

Volcanic soil, wind and very little rain

Santorini is a difficult place to grow anything. Its soil, known locally as aspa, is a mix of volcanic ash, pumice, sand and fragments of lava, with almost no clay and very little organic matter. Rain is scarce: summers are long and dry, and in recent years some growers have recorded less than 200 millimetres of rain in a year. And for much of the summer the island is swept by strong northerly winds, the meltemi, which can strip leaves and damage young shoots and fruit.

What makes viticulture possible is moisture from the air. Mists form over the sea and the caldera and drift across the island in the early morning, and humidity rises at night. The porous pumice in the soil absorbs that moisture and releases it slowly to the roots. Vines on Santorini survive less on rainfall than on dew, and on root systems that reach deep into the volcanic ground.

The soil has another, more unusual consequence. The root louse phylloxera, which devastated Europe’s vineyards in the nineteenth century and forced almost every grower to replant on resistant American rootstocks, cannot survive in sandy soil with so little clay. Santorini’s vineyards were never affected, and many of its vines still grow on their own roots. Growers renew the plants above ground every few generations while keeping the old root systems, some of which are said to be around three centuries old.

What makes Assyrtiko from Santorini distinctive?

Its acidity, above all. Most white grapes lose freshness as they ripen in a hot climate; Assyrtiko holds on to it, even when fully ripe. On Santorini, where yields are tiny and the vines are old, it produces concentrated dry white wines with a firm, steely structure, citrus flavours and the savoury, faintly salty character that wine writers often describe as minerality. Many writers also note their ability to age.

Santorini’s wines carry a protected designation of origin, recognised in 1971 and covering Santorini and the neighbouring island of Thirasia. The dry wines are made mostly from Assyrtiko, with smaller amounts of the local white grapes Athiri and Aidani allowed. The island also has two traditional styles worth knowing by name. Nykteri, whose name refers to working through the night, was originally made from grapes picked before dawn to avoid the heat and pressed the same day; today it is a fuller dry wine aged in oak. Vinsanto is a sweet wine made from grapes dried in the sun for around two weeks and then aged in oak for at least two years, turning amber with flavours of dried apricot and raisin.

Basket training as an agricultural adaptation

The kouloura is the most striking sight in a Santorini vineyard. Instead of tying vines to wires and posts, growers coil the long shoots round and round on the ground into a low, circular basket, with the grapes growing on the inside. From a distance a vineyard looks like a field of scattered wreaths, or of rough wild bushes.

The shape is a practical answer to the island’s conditions. The coiled shoots and leaves shelter the fruit from the meltemi and from the strong summer sun, and the low basket traps some of the night-time humidity close to the ground. A study comparing kouloura with conventional trellising found the basket-trained vines less water-stressed and better protected during heatwaves and high winds. It is also labour-intensive: everything, from pruning to picking, is done by hand, often bent double over the baskets.

Wine, landscape and continuity

Vines have been cultivated on Santorini for a very long time; the island’s wine producers point to archaeological evidence for some 3,500 years of viticulture, reaching back to the Bronze Age town at Akrotiri. In later centuries the island’s wines became a trade good. Under Venetian rule they were shipped across the Mediterranean, their sweetness and strength helping them survive long sea voyages, and the trade continued after the Ottoman conquest of 1579. Santorini’s sweet wine was also adopted by the Russian Orthodox Church for the Eucharist, and the island kept trading with Russia even in periods of war.

That long continuity is now under pressure. Historical estimates suggest the island once had several thousand hectares of vines; today about a thousand remain, often in small family holdings. Land has been lost to hotels and villas, labour is scarce, and successive dry years have cut harvests sharply. Some producers have added irrigation to parts of their vineyards while working to keep the old kouloura vineyards alive. The protected designation of Santorini’s wine has also been recognised as part of Greece’s intangible cultural heritage, a sign of how much the practice matters to the island’s identity. The broader history of the island, from first settlement to modern tourism, is told in our history of Santorini.

How to taste Assyrtiko on a winery visit

A winery visit on Santorini is most rewarding as a lesson in place rather than a tasting checklist. Start in the vineyard: look at the soil, how loose and pale it is, how little grows in it, and how low the vines sit. In the cellar or tasting room, ask how old the vines are and where the grapes were grown, since the position and age of a vineyard can shape the wine. When you taste, notice the acidity first, the sense of freshness on the sides of the tongue, and then whether there is a salty, savoury edge. If there is a Vinsanto to finish, it shows what the same grape becomes when the fruit is dried in the sun and the wine is aged for years.

There is no need to be an expert, or to drink much: a small taste of each wine is enough to see how the island’s conditions shape its character. For those who prefer not to drink, the vineyard itself, with its baskets of vines on volcanic ground, is the real subject of the visit.

What will the vineyards look like when the tour visits?

It depends on the departure. The tour runs in April and October. In April the vines are just coming into leaf, so the coiled shape of the baskets is easy to see on the bare volcanic ground. The harvest on Santorini usually begins in August, so by October it is over, and the vineyards are quiet, with the leaves beginning to change colour. Either way, the coiled shape of the kouloura is clear to see.

Why is Santorini wine relatively expensive?

Because it is so hard to make. Yields from old, unirrigated, basket-trained vines in poor volcanic soil are very low, all the work is done by hand, and the vineyard area has shrunk under pressure from development and drought, with some producers reporting harvests a fraction of what they were twenty years ago. Each bottle represents a great deal of labour from a small and shrinking piece of land.

From the vineyard to the rest of the journey

The winery visit comes on the same day as our excursion to Nea Kameni, the volcanic island at the heart of the caldera, and the two belong together: one shows the volcano that made Santorini’s soil, the other shows how people have learned to farm it. The next morning we fly to Crete, where the tour visits Knossos palace and, a day later, stops for a wine tasting on the way to the Minoan palace of Malia. How these stops fit together across Crete, Rhodes and Cyprus is explained in our Eastern Mediterranean islands itinerary.

A glass of Assyrtiko from Santorini is a small thing, but it holds a whole landscape: ash and pumice, a dry wind off the sea, old roots reaching down for moisture, and generations of growers bent over their baskets of vines. To see it at its source, in a small group of 6 to 14 travellers, explore the Santorini, Crete, Rhodes and Cyprus small group tour.