Calcareous soil is a soil type defined by Dr Ian D’Agata (2019, p.337 as any soil with high calcium and magnesium carbonate concentrations, adding that such soils are usually alkaline with very good drainage (unless the clay content is high), and may be low in phosphorus.

Tom Stevenson (2011) defines calcareous soil as ‘any soil, or mixture of soils, with an accumulation of calcium and magnesium carbonates. Essentially alkaline, it promotes the production of acidity in grapes, although the pH of each soil will vary according to its level of “active” lime. Calcareous soils are cool, with good water retention. With the exception of calcareous clays, they allow the vine’s root system to penetrate deeply and provide excellent drainage. Carbonaceous soil Soil that is derived from rotting vegetation under anaerobic conditions. The most common carbonaceous soils are peat, lignite, coal, and anthracite.’

Bibliography

Dr Ian d’Agata, Native Wine Grapes of Italy (University of California Press, 2014).

Dr Ian d’Agata, Native Wine Grape Terroirs of Italy (University of California Press, 2019), p.337.

Tom Stevenson (2011) The Sotheby’s Wine Encyclopedia 5th Edition by Tom Stevenson (Dorling Kindersley, 2011), p17.