We consider the the growth cycle of the vine to start after harvest.
The vines shed their leaves, and the trunks are sometimes covered up with earth to protect them from the cold winter. During the winter, each vine is pruned - all extra branches are cut off and then cuttings are burned in the vineyards. Normally, one long branch with 5 to 6 buds plus a spur with 2 buds are left for the following year's shoots. Pruning is a process requiring a great deal of care and is all done manually. This is just one of the many authorised pruning methods used in Bordeaux.
Support For The Vines
All pruning should be completed by the end of March, which is when the new growing season begins. With the warm weather, the sap starts to rise in the vines and then the buds burst. The shoots start to grow and the vines become green. When the new shoots are long enough, wires are lifted from each side of the row to hold the shoots in a vertical position. Another aim is to spread the bunches of grapes out as evenly as possible. If the bunches are packed too close together there is an increased risk of rot as the air circulation decreases. Exposing the bunches of grapes to just the right amount of sun is also very important.
The vine can grow several metres during a growing season if left untouched. The tops of the vines are trimmed with a tractor-propelled cutter several times during the summer. This keeps the vine in a manageable shape enabling good aeration and exposure.
Flowering
The vines usually flower in mid-June. The rule of thumb in Bordeaux is that harvesting should begin a little bit more than 100 days later. This varies according to the grape variety and the aspect of the vineyard. Flowering is a crucial time for the following year's harvest, since the next year's crop level is set during this time. If flowering takes place under favourable conditions (good sunlight as well as warmth), it is more likely that the following year's crop will be good, too.
