🪨 Albariza

Albariza (also the white soil of Jerez) is a soft white soil in southern Spain, where the vineyards for sherry grow around Jerez de la Frontera in Andalusia. The name comes from the Latin alba, white: in the dry months the fields dazzle the eye. It gives the area's vineyards their familiar look.

The protected-name specification (Consejo Regulador) calls it a soft white marl. It usually holds 25 to 40 % calcium carbonate, plus clay and silica from the shells of diatoms and radiolarians that lived in the sea covering the area in the Oligocene. The finest albariza, with the most lime and silica, gives the most select sherries.

Its main talent is holding water. In the rainy season its leafy structure opens up like a sponge and soaks in huge amounts. In summer the upper layer bakes hard and slows evaporation. About 600 litres of rain fall per square metre a year, mostly in November, December and March, against some 300 sunny days. Roots up to 12 metres long have been found at depths of up to 6 metres.

The soil is poor in organic matter, so growers plough 60 centimetres deep and manure it, and graft vines onto lime-tolerant rootstocks. In winter they pile ridges between the rows to catch rain. Palomino grows best here. The wine from these vineyards is sherry, amontillado among its styles.

Other soils sit nearby: barros (clays in the low ground) and arenas (sands near the coast), but they cover less. Chalk, a similar white soil, has its own page, though by the specification albariza is a marl.