AND CLIMATIC FRAMEWORK
Geological substrate: DIANO SANDSTONE in transition to SANT’AGATA FOSSIL MARL; 9 million years old (TORTONIAN STAGE).
The vineyard stands on the area of contact between two geological formations, Diano Sandstone and Sant’Agata Fossil Marl, so predominantly sandy strata alternate with layers of marl.
These deposits are of marine origin. The sandy layers were generated by submarine landslides which transported coarse sediments to the beds from coastal areas; as a matter of fact, it is not unusual to find fossils of molluscs which are typical of shallow waters (e.g. scallops). The marly strata, on the other hand, indicate conditions of calm on the sea beds that allowed fine sediments such as silt and clay to settle and accumulate.
Soil: BROWN, LOAM, MEDIUM CALCAREOUS, MATURE.
The soil that developed above the geological substrate inherited the characteristics of the formations below: a good percentage of sand (from the sandstone), and a medium quantity of silt and clay (from the marl) and of calcium carbonate (due to the sand, which is not rich in calcium carbonate). The percentages in which these components are found in the soil on Rocche represents one of the typical features which are important in understanding the cru. The good quantity of organic material and certain degree of evolution shown place it midway between white and red soils. The importance of this aspect is considerably significant: being fairly old – several thousands of years in fact – the soil has had time to transform part of its mineral components, which have dissolved to release nutritional elements and produce newly-formed clays. By combining with the clays inherited from the geological formations beneath, these newly-formed clays have great significance as they mediate the nutrition of the vine, enabling a regular, measured development through the vegetative season. The good sand content, on the other hand, means that the water retention capacity is lower than in more marly soils; this allows the plant to limit its vigour, and in fact at the beginning of the summer the vegetation on Rocche is already slowing down.
Climate and topographical framework: SOUTH-EASTERLY aspect; 340 m a.s.l. (1115 ft a.s.l.); gradient of c.10%.
The location of the vineyard sets it apart climatically from the rest of the Barolo growing area. Indeed, both the low winter and high summer temperatures are very subdued, generating a decidedly temperate microclimate. This is caused by its topographical position on a crest at medium altitude with no strong prevailing winds. Here it is possible to observe all the vegetative phases of the vine earlier: the bud break, flowering and ripening take place more than a week in advance. The olive trees and agaves that flourish in the gardens of the houses here testify to Rocche’s special conditions.
By Edmondo Bonelli, naturalist