Pieces of the puzzle...

 

What makes a great Bordeaux vintage?

First of all a long, balanced growing season without any extremes, meaning storms, long and heavy rains in September, October or even a scorching dry summer. The vine does not like extreme swings in temperature during the growing season. Several other problems may occur as well, see: coulure, millerandage, rot, spring frosts, oidium, peronospera... The weather in August is key in the quality of the vintage. Long september rains dilute the must and may result in less intensive flavours as well as low alcohol content.

Spring frosts

This can kill the vines in extreme cases (like in 1991) and can reduce the fruit set as the new shoots freeze away. Thus can reduce the crop of the vintage. Can delay flowering and as a result shorten the growing season (thus increase the risk that the fruit might not be ripe when harvested).

Coulure

Abortive flowering, thanks to cold spring weather or strong winds. Small berries fall off. This has a detrimential effect on crop size. Merlot is especially sensitive to this. Late pruning may help to avoid this as it leads to late flowering.

Millerandage

The berries within the bunch ripen unevenly. This is often the result of coulure.

Rot

Happens when rainy weather is suddenly followed by a sunny hot weather. Merlot with it's thin skin is especially prone to rot.

Oidium

This is a fungal disease also known as powdery mildew. The berries will split open, therefore the juice will be oxidised even before it enters the vinery.

Peronospera

Also known as downy mildew, it severely reduces photosynthesis and as a result delays or curbs ripening. The leaves are affected.

Groving season

From flowering to harvest...ideally this is around 100 days in Bordeaux, but extremes can occur, like the 2008 year when this number was 140 days, an extremely elongated one.