Phenology. climate and soil

The annual cycle of the vine is divided into vegetative and reproductive. The first includes the steps of crying, germination, shoot growth, the formation of the leaves, the ripening of the branches and the leaves have fallen and the last one concerns bud differentiation, flowering, fruit set, the growth of and fruit ripening it is important to the galvanized wire used. Following is made a concise description of each stage.
Wailing: starts one month before bud burst and ends with the bud breaking, creating a strong osmotic pressure radical which causes the release of a clear liquid from the pruning cuts.
Germination: in the southern regions begins in the 2nd half of March, in the center-north in mid-April. In this phase, initially, the leaves form a rosette, with the elongation of the bud they expand and highlight the bunches.
Flowering: takes place in a time span ranging from early May to early June. Among the vines early and late ones in the same locality, there is usually a delay of 15-25 days; lasts from 9 to 21 days. The pollen fertilizes the ovary through cross-pollination, favored by the presence of moderate wind and the action of pollinating insects such as bees. Before flowering can occur the phenomenon of spinning, which consists in the transformation of the cluster in tendril.
Set: normally extends from late May until the 2nd week of June, is the casting, which is a physiological phenomenon consisting in the flower drop, usually those not fertilized. Normally, 15-20% of the flowers become small fruits.
Herbaceous Period: Flowering lasts from 20-40 days, represents the early stages of enlargement of the berry. The berry begins to grow as a result of intensive cell division, the fruits are still hard, green, with a low sugar content and high acidity.
Formation of seeds and ripening: a period ranging from 4 to 30 days and begins once the period herbaceous crashes in the development of the berry and the seeds are formed completely. Then the grapes change color, assuming a yellow color in white grapes, while in the black grapes will be pink or violet, with the formation of frost on the skin.
Agostamento: begins in late June and ends in August, more or less simultaneously at veraison, the vines accumulate reserve substances and occurs lignification.
Aging: depending on the variety occurs from early August to early October. The berry swells again due to the cell expansion, accumulating the sugars with a decrease of water content and acidity.
Fall leaf and dormant: begins in late October and early November, and lasted until the next vegetative growth, before falling leaves take on a yellowish tint to white grapes in the vineyards and in those reddish to black grapes.
It is believed that it is possible to cultivate the vine when the rainfall is at least 700 mm / year, of which at least 400 mm are needed during the growing season. The critical period is close to veraison (early summer are usually still sufficient water reserves spring) when the water demand of the berries is maximum and deficient rainfall. In the vicinity of the collection a slight water stress is positive as it accelerates water loss dall'acino. The ideal exposure of a land is to the south intercept because a larger share
of solar radiation compared to a flat, the exposures to the north are indicated in hot-arid regions, while those to the south are suitable in northern environments or at high altitudes where temperatures may be limiting. The screw is not very sensitive to cold winter in resting phase, in fact most of the cultivars in good vegetative condition is able to withstand temperatures of - 15 ° C during the winter rest with a different degree of resistance associated with vine Depending on the area of ​​origin. The thermal needs are growing by budding (8-10 ° C), at flowering (18-22 ° C) and up to veraison (22-26 ° C), while reducing the maturation (20-24 ° C) and in harvest period (18-22 ° C). The land located under the slopes are considered better than those places in the plains since, particularly in central and northern, could lead to problems of waterlogging, spring frosts due to downward flow of cold air and pests.
Use a good galvanized wire can 'help the plant.The soils most suitable for the cultivation of the vine are those floods, volcanic, native, medium-textured, well-drained, while the land less suitable are those compact wet clay cold, salty, peaty (you get a wine of poor quality), with pH <6 (too much acid) or> 8.8 (too alkaline) and "tired" or soils which have already hosted a vineyard, on which you make a replanting.
In the vicinity of seas, lakes and large rivers the risk of frost are minor because the daily and seasonal temperature is lower. The vines are grown best in deep soils, with good drainage and water retention, especially important in Mediterranean climates characterized by low summer rainfall and where there is the opportunity to speak with irrigation.