Assyrtiko is the white grape variety primarily grown on the island of Santorini.
The grape is indigenous to Santorini and is the island’s flagship variety. It thrives in exceptionally dry, windy conditions and in porous volcanic-ash soils. Because rainfall is scarce, many vines rely on nighttime humidity and dew for moisture rather than conventional irrigation.
Santorini growers traditionally train the vines into low, circular baskets called kouloura. The grapes grow inside these baskets, protected from the island’s strong winds and intense sunlight. Many vineyards also contain very old, ungrafted vines because Santorini has largely avoided phylloxera damage.
Assyrtiko is prized for retaining strong acidity even when fully ripe. Wines made from it are commonly dry, citrusy, mineral-scented and sometimes notably saline. Athiri and Aidani are also traditional Santorini grapes, which can cause confusion, especially because they may be blended with Assyrtiko in wines such as Vinsanto. However, Assyrtiko remains the island’s defining white grape.