The cost of a Bordeaux hail storm

Vineyards all over the world can fall prey to the ravages of the elements. In the New World, the main problem is drought; in the Old World, it's frost and hail. 

I owned a vineyard in Bordeaux from 1990 to 2005. In my second year (not my first, luckily), a frost driven by cold north winds from Russia hit the area in late April and destroyed 70-80 per cent of everyone's crop in just 15 minutes. The rich and famous (notably Chateau Petrus) had helicopters to help the air circulate - all that happened was that more cold air was driven onto the vines, causing even more damage. 

To make matters worse the tiny crop that did survive was terrible. Several struggling vignerons actually shot themselves in the weeks following the frost.

Wine-growers can insure themselves against these climatic extremes, but with a premium of about 3 per cent of the insured value for each wine category, very few can afford it.

The most severe threat of all is hail. Not the hail that we are used to, but hail the size of golf balls, even tennis balls. A few years ago, a resident of Bergerac had his brand new Bentley completely written off by hail, so it's not hard to imagine the damage it can do to vines.

Bordeaux was hit again earlier this month with its worst hailstorm for 10 years. In St Emilion alone, 3,000 hectares of vines were affected and there was also widespread damage in Margaux - their loss of crop could amount to anything from 20-60 per cent, depending on the intensity and size of the hailstones and the area of the storm itself (within 5m of a hailstorm's edge, there is no trace of damage - it literally cuts a swathe through a vineyard).

The only known preventative measure against hail is to fire rockets into the storm clouds to try and disperse them - and this is just what these famous Bordeaux appellations did. It may have mitigated the damage slightly but, as with using helicopters to combat frost, it is a very expensive solution with absolutely no guarantee of success.

But it just goes to show how much money is at stake here. Chateau Latour's harvest is worth £40-50 million in an average year, so the odd rocket is probably covered by the petty cash! ·