Viticulture in Jerez 2. The work in the vineyard

According to the old saying "Las Ninas y las vinas dificiles son de guardar" or girls and vineyards are difficult to look after. Let's just stick to the vineyards! In order to get the best grapes and therefore the best wine, the vineyards must be tended with unceasing care. Over many centuries the vines have been selected as the most suitable for the prevailing soils and climate and have adapted to it. People have learned how to get the best from the vines and developed the wines accordingly and in concert with nature.

Traditional "bienteveo" to keep a watch on the vines

There are three varieties of vine used in Jerez:

Palomino Fino

The most widely planted, as it is responsible for all styles of dry Sherry, Pale Cream and a few light table wines. Yields of about 80 hectolitres per hectare (Hl/Ha) are normal. The grapes are quite low in sugars and acidity, which is a problem for the table wines but fine for Sherry. Its must has a tendency to oxidise, but that isn't a problem either. It also makes a delicious table grape.

Pedro Ximenez (PX)

This variety is responsible for the great sweet Sherries and for sweetening blends. It is the second most widely planted and only a short distance behind Palomino. The skins are thinner making it more disease prone, but it produces higher levels of sugar and acid and yields well. Nearly all PX grapes are dried in the sun (asoleo) into dark raisins which produce tiny amounts of intensely sweet must. The wine sold as PX, especially when old, is a fantastic experience.

Moscatel

The least extensively grown variety, and also used for sweet wines. Moscatel grows on the lesser soils, clay and particularly sand, much of it around Chipiona on the coast. The grapes also undergo asoleo and make lovely sweet wines which are sold as such or also used in blending. As a dry wine, it is often blended with Palomino to produce more interesting table wines.

In 1894 the dreaded Phylloxera louse reached Jerez, and as it had already done in most of viticultural Europe, destroyed the vines by attacking their roots. As the louse came from America, and american rootstocks were resistant to it, Jerez was replanted on american roots with the Vitis Vinifera (the European vine genus responsible for wine grapes) scions grafted on top. To this day all vines are grafted.

The vines here have a useful commercial life of about 30 years. Throughout the life of a vine the quality gets better, but as it ages, the yields can drop to unsustainable levels and it will be replaced. Vine planting is normally done by the system known as "Marco Real", where plants are spaced along the rows at 1.5 metre  intervals, and the rows are 1.5 metres apart. This most traditional system allows good passage of air, workers and machines and is used generally. The other system, known  as "Tresbolillo" allows a few more plants per hectare, but is otherwise less practical. Most vines are trained along a wire cordon.

Once the vines are established, they must be pruned. Pruning in its various forms is important; to set the shape of the vine for production; to keep the vine healthy; to maximise quality, and sometimes to allow best access for harvesting machines. Normally pruning is carried out in late autumn after the harvest, and the system most widely used is called "vara y pulgar" which resembles your forearm (as the vinestock) with extended thumb and forefinger. The forefinger is allowed about 8 buds which will produce fruiting canes in one year, and the thumb 1 or 2,which will produce a vara for the next year, the previous vara being pruned back to 1 or 2 buds. So the pruning alternates annually. In spring, a "green" harvest takes place with the removal of excess buds to avoid overproduction. If you overproduce, you end up with lots of thin wine, so the idea is to produce less but better wine. Pruning is also applied to remove excess foliage which might hinder the access of sunlight and fresh breezes, or retain humidity with the attendant risk of moulds or rot.

Traditionally the harvest ("Vendimia") starts on the 8th September, the birthday of Our Lady, and this is the start of the Fiesta de la Vendimia (the harvest festival). The weather being what it is, however, the date is decided by the ripeness of the grapes. Palomino is picked at about 11 degrees Beaume (a scale of sugar content) and PX at about 12.8. Global warming has now advanced the date to late August. In the run up to the harvest, the bodegas are all busy checking the grapes' sugar levels, cleaning their equipment and organising pickers - where there are no mechanical harvesters.

If picked by hand, the bunches of Palomino grapes are put into plastic crates to avoid them being squashed and quickly sent to the "lagar" (press house). The PX grapes follow a different path. Out in the fields huge lines of esparto grass mats are laid out where solar exposure is best. Every few metres curved rods are fixed over them. Millions of bunches of PX grapes are then laid out on the mats to dry out in the sun. At night, to avoid humidity from the dew, sheets of plastic are draped over the rods, and next morning the sheets are removed and the grape bunches turned over. This process called "asoleo" or sunning, which lasts up to two weeks, results in bunches of raisins which will make the sweet wines. During the asoleo the grapes lose 70% of their weight due to water evporation, so the sugar content is less diluted and doubles from about 13 to about 25 degrees Beaume. Obviously the amount of juice available on pressing is minute, which explains the extent of vineyard needed for PX cultivation.

This process is used widely in Andalucia, and in Chipiona, one of the Sherry towns specialising in Moscatel, they call the process "Pasil". The only difference being that the rough sandy soils absorb more heat which is radiated back at night through the loose-knit sheets of plastic on which the bunches are laid.