Turns out, it’s a pretty niche subject, and not a huge amount is readily available online. However, thanks to Margaret Rand’s 2015 piece in the World of Fine Wine Magazine, entitled “Chalk Talk; The Geology of English Sparkling Wine”, I was able to get a light schooling on what one of Rathfinny’s most prized assets brings to the table.
Full disclosure, I am about to massively precis, and possibly butcher, one or two elements of Margaret’s well-researched and vibrantly-written piece, an exhaustive article which explores whether the parts of England that share the same chalk as Champagne have just cause to celebrate the fact. Interestingly, it also covers the wider question of whether geology has an impact on a wine’s flavour.
Diving right in, one of chalk’s key super-powers, as Margaret Points out, is how it handles water, with one cubic meter holding 660 litres of water. My simple brain then asked the question, what’s the use of retaining water in a country that’s not short of moisture? Well, It’s the slow-draining property of chalk that’s the clincher, along with its strong ‘capillary action’. Obviously. ‘Capillary Action’ is the force that allows soil to retain moisture and regulate its movement, in the same way porous materials like sponges soak up and hold liquid. It’s a phenomenon that allows water to move upwards or sideways within chalk’s micropores, against the force of gravity.
So, chalk does its best to hang onto water, forcing the vine to fight for it, which in turn develops a strong capillary action of its own. This push-pull situation going on at 500mm below the ground means that the vine is effectively getting a work-out, so you are allegedly left with fitter vines. Vines also love chalk because it’s rarely saturated and has good heat-storage properties, allowing it to absorb and store heat in the summer and restore it during the winter months. Genuinely fascinating stuff, but does chalk actually do anything to the flavour?
