Definition: Vineyard work

The aim of the annual wine-growing cycle is to preserve the life and health of the vine, and to control the development of the foliage, whose vitality enables the photosynthesis essential for the ripening of the grapes. The order in which these tasks are carried out is as follows:

Pruning takes place from November to March (approximately 200 hours per hectare). It is carried out according to very specific rules aimed at deliberately limiting the vine's yield by prohibiting Next come the "green tasks": tying, from February to April (90 hours per hectare), and attaching the vine's framework to the wires, which is done around mid-April. Vegetation begins to grow, which is known as "bud break". It is then necessary to control its development, as excessive growth would compromise the quality of the harvest. Lifting (120 hours of work per hectare) is carried out in two stages from mid-May to early July. The vegetation is directed upwards so that it benefits from the light. The operation is carried out before flowering using wire or other types of fasteners (straw, raffia, etc.). Placed above the vines, these wires allow the fruit-bearing shoots to be attached, preventing them from falling to the ground.

Trellising then involves placing clips after spreading the foliage evenly, to attach the vine shoots to the lifting wires in a raised position (the rows reach a height of around 1.20 m). The aim of lifting and trellising is to promote photosynthetic activity through good aeration of the foliage, which limits humidity around the bunches, thus combating the development of botrytis. The proper distribution of sugars (synthesised by the leaves) between the plant and the fruit is a major factor in the quality of the grapes. Debudding removes unnecessary young shoots and promotes fruit-bearing branches. Sometimes it is even necessary to remove excess buds (fruit debudding). Trimming and pruning (approximately 60 hours per hectare) is essential from July until the harvest, in order to cut away superfluous shoots that always seek to climb towards the light of the sky, risking depriving the bunches of vitality. The humus content of the vineyard soil is replenished by shredding the shoots and adding organic matter, such as compost made from plant matter. Additional mineral fertilisers are used to prevent any deficiencies. These are carefully balanced according to soil analysis. These additions also promote the essential microbiological activity of the soil. All vines can be attacked by cryptogamic diseases, some of which attack the foliage or bunches: mildew, parasitic red spot, powdery mildew, grey rot (botrytis chinera); others attack the vines themselves: esca, eutrophy and excoriose.

Other predators include insects such as mites, grape worms (especially cochylis), moths, etc. Appropriate treatments are carried out with the advice of specialists and the utmost concern for the environment. Advances in modelling have made it possible to limit the number of treatments in a rational manner.

Hail represents a very serious and unpredictable danger to the harvest. For example, on 2 July 2000 in Champagne, violent hailstorms struck the grapes of the future harvest. The hailstones, which were the size of pigeon eggs, corresponded to rainfall of 20 to 30 mm and devastated several thousand hectares. The Marne Valley, the Épernay area, the greater Marne Valley as far as Bouzy, the north of the Montagne de Reims, the Vitry-le-François region and, in some cases, Barbonne-Fayel were seriously affected. Of the nearly 4,000 hectares affected, the average rate of destruction of the grapes was around 50%. The estimated area destroyed at 100% is equivalent to 1,900 hectares. Large areas of terroir were affected by this catastrophic event, which left behind a scene of desolation. The harvest will be significantly reduced for many winegrowers in the most affected municipalities. Faced with this type of very late hail, there is unfortunately no hope of vegetation regrowth, which would allow a new generation of grapes from the year 2000 to reach maturity. Experiments conducted in recent years have also shown that specific green pruning is ineffective. All efforts have been focused on effective protection against mildew in order to preserve as much active foliage as possible for the accumulation of reserves essential for the preparation of the next harvest in 2001. The following winter pruning was made complex and tedious by the choice of damaged pruning wood, making it difficult. Large hailstones destroyed the bunches and damaged the shoots. Damaged wood also compromises the following year's harvest. Protection against spring frosts is sometimes necessary, given the northern location of certain vineyards, which are particularly vulnerable to frost, especially on young buds. Protection is provided by various methods: localised air heating systems at ground level using paraffin candles or oil heaters; systems that maintain a water-ice balance at 0°C by spraying water on the vegetation during periods of low temperature (night-time, dawn); air circulation systems (wind machines or propellers). See vegetative cycles.