SommDomm on how geology shapes taste

Alongside this article, I’ve written a tribute to the late Peter Hall of Breaky Bottom, the artisan whose South Downs vineyard, grown on chalky soil, helped define the English style of flinty, orchard-fresh sparkling wines, echoing those from Champagne across the Channel.

Yet parts of Southeast England arguably share more geological kinship with Burgundy, thanks to the interplay of clay and sandstone with calcareous soils. The less-discussed Wealden Dome occupies a larger swathe of Sussex and Kent than the chalky South Downs.

So how do these varied geological zones influence the taste and character of wines made from key grape varieties – Chardonnay and Pinot Noir?

Geological soil differences

The Downland vineyards of Sussex – and neighbouring Hampshire and Kent – sit on top of an ancient seabed of chalk (calcium carbonate), layered with flint from decomposed sponges and topped by thin loam. These free-draining, alkaline subsoils retain and release water as needed, making them ideal for premium sparkling and still wines. Chardonnay, in particular, thrives here – on more fertile soils it tends to favour vegetative growth over fruit concentration.

Chardonnay grown on chalk typically yields precise, tight wines with citrus and stony flavours, good mid-palate tension, and purity. Pinot Noir from chalk shows freshness and clarity of red fruit, though often with less body and weight than its clay-grown counterparts.

Wine writers often romanticise a ‘chalky’ or ‘mineral’ taste in Chardonnay. But scientifically, such flavours cannot be directly imparted by rocks in the soil – these are insoluble and cannot be absorbed by vines through transpiration, which involves the movement of compounds in liquid from roots to fruit or leaves. Nor can they volatilise into aromas detectable in the finished wine.

The Weald of Sussex and Kent – edged by the Tunbridge Wells sandstone ridge – comprises heavier clay soils, often mixed with sand, sandstone, and ironstone. These soils retain more nutrients and moisture, with potential for producing wines with greater body, richer texture, and fuller mid-palate weight. Vines here experience less stress, allowing for fuller berry development and softer acidity compared to those grown on chalk.

Wealden District, named after its geological bedrock, hosts around 20 vineyards, mostly smallholdings and diversified farms that have changed hands between yeomen farmers and newcomers. These contrast with the more static aristocratic estates – Firle, Wiston, Goodwood – that line the South Downs.

Burgundy comparisons

Wine styles here invite comparison with Burgundy. The limestone slopes of the Côte d’Or favour linear, pure expressions of still Chardonnay – think Puligny-Montrachet or Saint-Aubin. Meanwhile, the heavier iron-rich marl soils of Pommard and Gevrey-Chambertin yield muscular, full-bodied, meaty wines.

Sussex has no legally designated premier or grand cru vineyards (Burgundy has 33), but it does have a Protected Designation of Origin (PDO) covering the entire county. This broad classification has sparked debate among aficionados, who argue that too many distinct terroirs are being shoehorned into a single PDO, diluting typicity. Kent has yet to declare a PDO, though rumours suggest plans to distinguish chalk and clay sub-regions.

What to expect from different soils

From Sussex or Kent Downland chalk-grown Chardonnay, expect a fresh, lithe wine with citrus, white-flower, and hedgerow notes. Wines from the Weald may offer more generosity – orchard or stone fruit, a hint of richness, and a fuller mid-palate.

For Pinot Noir, chalk sites tend to yield fine-boned wines with red-berry fruit, bright acidity, lighter colour, and delicate tannins. Clay-grown examples lean darker – richer fruit, firmer tannins, and more structure.

Take Gusbourne in Kent, for example – with vineyards on both Wealden clay/sandstone and Sussex chalk/flint. Recent vintages have begun to demonstrate how these soil types behave, supporting the theory: chalk downland equals finesse, Wealden clay/sand equals fullness.

Artelium’s ‘Artefact’ range showcases this contrast. The 2020 Chardonnay ‘Artefact #2’, from their home vineyard on clay, won multiple medals and was described by judges as having a ‘creamy oatmeal palate’ with ‘depth and texture.’ Their Madehurst site, on South Downs chalk, recently released ‘Maiden Harvest Chardonnay 2024 – Artefact #12’. In contrast to #2, this wine shows chalk’s finesse – precise citrus and floral aromas, with a concentrated palate of golden delicious, apricot, and brioche.

Mount Harry vineyard near Lewes, planted and operated by Dermot Sugrue (formerly of Wiston), also sits on pure chalk. His most expensive cuvée, ‘Boz’ (named after his brother), is what he considers a ‘grand cru’. His latest release from Sugrue South Downs is a Pinot Noir from Crouch Valley in Essex – grown on London clay – showing light body, bramble, violets, and herbaceous notes that evolve into chocolate as the wine opens. Essex, at least in still wine, is beginning to challenge Sussex’s supremacy.

Mereworth in Kent, between Tonbridge and Maidstone, is planted on greensand. Founded in 2017 by William Boscawen on the family farm, it produces an exceptional sparkling rosé exclusively from Pinot Noir.

Bolney, also on greensand, was planted by chance according to former owner – and now head of Plumpton College’s Wine Department – Sam Linter (see ROSA #8 and #14). Their Chardonnay shows more body and warmth than some chalk grown examples, while their Pinot Noir leans toward generous red-berry fruit with greater amplitude.

All things being equal

The geology of Sussex and its neighbouring counties offers a vivid illustration of how soil type shapes the expression of Chardonnay and Pinot Noir – in both sparkling and still wines. For those seeking a deeper understanding of English wine, identifying whether a vineyard lies on chalk, clay, or sandstone can be a useful indicator of style. However, winemaking choices are equally influential. Some larger, long-established producers – such as Chapel Down in Kent, Ridgeview in Sussex, and Camel Valley in Cornwall – source grapes from multiple regions, so what’s in your glass may not reflect the soil of their home county.

It’s said that great wines are made in the vineyard – and the starting point is the soil. All things being equal, Chardonnay or Pinot Noir from clay or sandstone may offer earlier enjoyment, while chalk-grown wines invite contemplation, subtlety, and longer ageing.