At last we had some rain in Bordeaux. 20mm fell on evening 13th September in a grand storm where 20mm of water fell onto parched vines. It rattled windows and tripped electricity but fortunately no hail fell as predicted. A huge sigh of relief for wine makers here and a deep sleep followed. It just served as a drink for the thirsty vines. For the last few days since the same has fallen again and the temperatures have falled to early 20s more normal for this time of year, mid September. Autumn has arrives after this long, hot, dry ‘lizard’s’ summer.
So the vines who had slowed down have woken up, their metabolism had started working at 100% again and ripening is happening again under the autumn sunshine with harvest being expected some 2 to 3 weeks away. Due to the lack of rain since mid June, the veraison (changing of colour) was very slow and not completed in some bunches (which means some green berries in the bunches).
Although we are all so thankful to have this change we do not want this weather to stay now and would like to see bright sunny though cooler days until harvest which will be around 5th October, late due to the slow flowering, veraison and heat which slowed down the vine’s metabolism and ripening.
The young vines particularly appreciated the rain but mainy particularly in Pomerol and the Medoc suffered with many leaves turning brown and falling. They do not have the deep roots to reach the water table yet.
I was surprised given the dryness of this 2016 ‘lizard’s’ summer, that the majority of the vines remained green and stress free particularly in St Emilion where the limestone and clay act like a sponge giving water when it is needed even in this dry conditions.
The berries still remain small and concentrated but at least now the vines are able to finish ripening. What happens when a grape ripens? Two separate phenomena happen. Inside the grape the juice becomes sweeter (more and more sugar present) and the acidity drops. This is called technological ripeness. There is another action that happens that is unrelated with this and it involves the ripening of the skins, physiologocal ripeness or phenological (phenolics) that of the tannins, colours (anthocyanins) and aromas. As the grape ripens the skins get thinner and their aromas (roses, violets, blackcurrant, cherry, raspberry, cinnamon) are able to come to the fore and really released during fermentation into the wine. (Merlot below at Larcis Ducasse St Emilion 14 September 2016).