The vignerons of France coined the term ‘Terroir’ for the complex interaction between land, soil and microclimate that influences a vine’s grapes.
Gardeners intrinsically understand this fancy concept: which plants grow in acidic or alkaline soils; those best suited to sandy soils; or which can support heavy clay; they know which plants suffer from frost, wind or sea-salt. They don’t call it terroir, though. They call it gardening. Farmers call it farming.
Like any other plant, barley (a grass) has roots nourished by minerals in the soil, originating from the bedrock itself after millennia of erosion. Different soil types, from sandy loam to peaty histosols, and their associated minerals and consistencies influence the grain as they do the grape. Minerals enter plants mostly through the root hairs so the composition and texture of the soil is influential. Stony soils radiate extra heat and barley ripens sooner.
Terroir is not the soil alone, but the lay of land too. In the barren days of winter, dark patches of soil in a ploughed field give away the pockets where excess moisture collects – a risk of rotting the roots of any crop. Or frosty air concentrates on a still, spring night as deadly to any burgeoning crop as a fatal disease.
Farmers know a wind-breaking ridge of trees not only provides protection but reduces evapotranspiration, improving growth. Steeper slopes have thinner soils with better drainage as repetitive rains wash the soil down hill; conversely, flatter ground where that soil accumulates, is deeper and richer producing lusher plants.
Localised geographical anomalies create microclimates. The Combe Brûlée in Burgundy’s famous Vosne Romanée vineyard, earns its reputation as the Burnt Hollow, from the Pinot Noir grapes that ripen best in this geological sun trap. A vigneron is a farmer too. And they know their land as intimately, each dip and fold.
As a vineyard’s terroir allows different and distinct wines to be made – even from the same grape variety – likewise specific farms allow us to distill distinctive spirits even from the same variety of barley. There are two farms for each of the main 19 soil types of south eastern Ireland.
For much of the whiskey industry barley is a mere commodity purchased on global markets by price. The industrial constructs of continuity and conformity are key. Terroir is irrelevant. Barley is just barley.
Yet barley is the genesis of single malt. The entirety of a new spirits flavour is derived from flavour compounds that originate in the grain; that’s what makes single malt the most complex spirit in the world. And that grain starts in the field: influenced by landscapes, sustained by microclimates, nourished by soils. Terroir.