Born of fire: Terlano’s vineyards nestle like sun terraces in red porphyry rock of volcanic origins. A type of Bolzano quartz-porphyry, it comprises a sequence of acidic lavas and volcanic eruption products with intermediate sediment layers. The mainly quartz-rich rocks are composed of minerals like quartz and feldspar embedded in a fine-grained to glassy matrix.
In Terlano the near-vertical rock face consists of various formations such as ignimbrites (rhyolites and glowing avalanche deposits), tuff, conglomerates and lava flows. As a result of repeated mudflows along the Rio San Pietro, the erosion products of this geological succession were transported down to the valley, forming a debris fan that now constitutes the subsoil for the Terlano vines.
The topsoil in Terlano contains a high proportion of coarse grains of siliceous stone and sand. With its skeletal character, the soil quickly warms up. The relatively limited fine-grain fraction is mainly sandy to sandy loam.
pH: neutral to slightly acidic
Carbonate content: low to moderate
Soil type: mainly sandy to sandy loam
Soil depth: high (>2 m)
Skeleton fraction: very high
Rock: predominantly siliceous (porphyry)
Field capacity: minimal to low