Grafting

The grafting is an operation done in the vines resistant to phylloxera. This operation, which allows the preservation of European viticulture, consists in making the union of a vine already with roots with the vegetative material of a selected grape variety.

Nowadays, only certified rootstocks are used in the new vineyards, being the most common the SO4, the 196-17 and the 161-49. The rootstocks used have to consider two factors:

• the type of soil where it is going to be planted
• the characteristics of the grape variety where it is going to be grafted

The most common grafting method in this region is the scion. During the vegetative resting period the vine's trunk is cut and, according to the root's diameter, one or two incisions are made. A two or three bud's scion with one wedge-shaped end is put in the open incision. The graft is then tight with raffia and covered with earth.

Pruning

Pruning is an operation done every year during the vegetative resting period. Due to the great profusion of this region's vines and due to the natural mechanisation difficulties this operation presents, pruning is a hard operation that requires much manual work.

What makes pruning a demanding operation is the fact of being necessary to balance the potential crop left in each vine. And here is where the main problem to mechanisation lies, as each vine has to be treated individually. From that correct balance will depend the regular development of the plant and the relation between quantity and quality of the grapes.

A pruning operation allowing an excessive development of the plant during the following vegetative cycle will give origin to a high production of low quality grapes. On the contrary, a too severe pruning will cause a too intense growing of the leaves affecting the grape's quality.

Bending the cane

The bending of the cane is done at the same time as the pruning and consists in bending a cane and tying it to a wire to encourage the buds to burst.

In this region, the bending of the cane was only used with trellised vines, as this is not possible to do in the "enforcados" and stakes guiding systems. Nowadays, only the vines set up in the sylvoz system require this operation.

The advantage of bending the cane for the productive process is that it allows the control of the bud burst. Nevertheless it needs more manual work, consequently affecting the production costs.

Irrigation

The vine needs water in three moments of its annual cycle:

• in the beginning of the vegetative growing, early Spring;
• after the end of the flowering, when the berry starts growing;
• in the maturation phase, to allow the acids to change into sugar.

Due to the climatic conditions of the Vinho Verde region, usually it is not necessary to irrigate, except in the third case.

In the months of July and August, considered as dry, as the medium precipitation is under 30 mm, it is common to have at least two or three rainy days. This is, in general, enough for the vine. However, when the year is extremely dry, the bunch veraison is hardly achieved without irrigation.

In the years with much rain the balance between quality and quantity is usually affected and the quantity prevails (the people say that a good wine has to go hungry and thirsty). In dry years the quality may sink with the quantity, if corrective measures aren't taken.

Irrigation, regarded as a measure with the aim of correcting the climate unbalances and not as a technique to artificially increase the production in prejudice of quality is something that the winemakers of the Vinho Verde region can not give up.

Portugal assumed the compromise of forbidding the vine's irrigation in the European Community Treaty Agreement. However and as the Vinho Verde wines have to benefit of special conditions from the Communities Council before the transition period, it is expected that this matter will receive a special handling.