Nitrogen in Vineyard. Effect on plants. Dosage and properties.

Nitrogen in vineyards: Nitrogen is the nutritive element that favors growth and vigor in the vine.

It is one of the fundamental elements (Macronutrients) in the constitution of vegetables, since it enters the composition of chlorophyll.

It is assimilated by the plant under the forms of ammonium nitrogen and nitric nitrogen, although its faster absorption is in the nitric form.

According to some tests, it has been shown that ammonia nitrogen has a greater influence than nitric on the growth of shoots and roots and nitric induces the growth of clusters due to its greater number of flowers and its concentration in the leaves.

For this reason, N is considered a quantity factor.

2- When is the N needed?

The vine has a continuous nitrogen absorption from sprouting to veraison with a maximum requirement in three moments:

1. The curdling or sifting, in such a way that it should be noted that the shift is often due to the lack of N at that time.
2. At the restart of active growth after sprouting.
3. A third moment, the rapid thickening of the fruit.

3- Effect of nitrogen in vineyard: 

Its effect is manifested by an intense green of the leaves, but you have to be very careful with nitrogen fertilization, since the vine is not very demanding on it and an excess of nitrogen gives rise to negative effects such as:

1. Excessive developments.
2. Poor fruit set, with the consequent loss of harvest, especially in vigorous varieties and with vigorous rootstocks.
3. Delay and incomplete maturation and makes it difficult for the wood to dry properly.
4. Greater sensitivity to cryptogamic diseases ( downy mildew and powdery mildew of the vine ).
5. Nutritional imbalances causing potassium deficiencies …

4- Nitrogen deficiency or deficiency in vineyards produces:

1. Poor development of the plant, reduces growth and production.
2. Pale green or even yellowish hue of the leaves, the vines have a green-yellowish appearance.
3. Poor fruit set.
4. Premature fall of the leaf in autumn.

5- Fertilization Plan of the vineyard, nitrogen in vineyard:

There are several authors who for years have calculated nitrogen extractions in vine cultivation and it is estimated that for a production between 40-120 Hectoliters of wine, the consumption of N ranges from 40 to 90 kg or UF.

Consumption of N has also been established for 1000 Kg of grapes produced and the values ​​of N consumed are around 7 Kg of N or 7 FU.

The fertilizer doses will be carried out based on the analysis of soils, rainfall, variety, rootstock and the amount to be produced, but average values ​​can be established, in rainfed cultivation and average rainfall, depending on the production :

The needs of the subscriber vary, in rainfed from 30 to 60 UF / ha.

– From 4 to 6,000 kg per Ha the contribution must be between 30 and 50 UF (Fertilizer units).

– From 6 to 8,000 kg per Ha the contribution must be between 40 to 60 UF.