Syrah: Origin, taste and characteristics
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4 Feb 2023
The term planting density defines the number of vines per hectare present in the vineyards. This parameter is the result of two variables that depend on two distances: the one between the rows and the one between the logs (called planting spacing).
Indicatively, depending on the planting spacing, a vineyard can be defined:
The density of a plant determines a precise breeding system, almost definitive once chosen, which is why over the years it has always been a factor at the center of studies and research.
Since the 1990s, inspired by the French model, numerous experiments have been carried out, leading to a trend towards thickening the systems. The reason is simple: planting density causes greater competition between plants in the vineyards to search for the nutrients present in the soil. This competitiveness inevitably reduces the development of the vegetative part (leaves and fruits), leading to smaller bunches and berries.
Considering that the reduction in the size of the berries involves an increase in the ratio between the surface and volume of the berry, this would result in a higher quality production. The roots also have a tendency to prefer developing in depth, rather than laterally, thanks to this propensity they explore the soil more in search of water and fundamental minerals that give quality to the grapes and therefore to the wine. Not only that, a less lush plant will also be less exposed to diseases and parasites such as fungi, bacteria and viruses.
Over the years, the trend of densification has been questioned, and it has in fact been understood that the choice of density for a system cannot be reduced to these parameters. Other variables must be taken into consideration such as: the soil, the climate, the oenological and qualitative purposes, the rootstock and the vine, the training method and the ease of cultivation operations.
The climate has a significant impact on the choice of planting density
The choice of planting density in a farm must be made according to the pedoclimatic environment, i.e. the soil and climate, the vine itself, the type of production you want to obtain, and the vineyard management techniques (mechanisation). An aspect of fundamental importance, especially in recent years, is the climate, which plays an important role in the choice of the farming method. When dealing with low temperatures it is advisable to choose low density cultivation, to allow the grapes to ripen, running the risk of the buds freezing in spring, due to their proximity to the ground. To overcome this problem in hilly areas, north-south exposure is recommended, which favors photosynthetic yield and reduces the risk of spring frosts.
Differently in warmer areas, higher density farming methods allow the achievement of greater quantities of sugar. In the hottest areas, the east-west exposure avoids direct sunlight in the central hours of the day. With climate change and increasing desertification it is necessary to better manage the water stress of the vine, which is a determining factor for obtaining quality grapes. From this perspective, it is essential to guarantee greater development of the root system, and this can be done by increasing the inter-row space.
In the case of the Alessandro estates, explanting was necessary given the high longevity of the vines.
The plants carried out since the 2000s, being high density, have aged prematurely.
Furthermore, the high planting density associated with the varied climatic conditions of the last decade has led to obtaining grapes with a high sugar content and consequent high alcohol content, with all that entails.
The change in the climatic environment, therefore increasingly heavy and intense rainfall events even in short periods, and very high temperatures in summer have naturally led to a different management of the land.
In high-density systems it is possible to work with specific machines known as over-riding machines suitable for loose soil and almost always in tempering. In recent years the land is increasingly found in non-optimal working conditions, and over-riding machines are not capable of carrying out the works, this is why it is necessary to have less dense systems so that we can enter and carry out the work with normal tractors.
It can therefore be concluded that the variation in planting density comes from high density vineyards, in the specific case of Tenimenti d Alessandro with 8,000 vines per hectare, it brings numerous benefits, including better land management and better management of the vegetative wall. Furthermore, another aspect not to be underestimated is the better airing of the leaves which determines less humidity, fewer phytosanitary attacks and allows us to reduce the quantities of copper and sulfur in the fight against phytophytry.