When is the best time to fertilize our vineyard with nitrogen

 

 

 

 

Knowledge of intake periods is particularly useful, but the movement and distribution of added nitrogen in both periods is of particular interest.

 

 

It was found that during the veraison period only 22% of the nitrogen content in the plant corresponded to the amount added in early summer (after flowering). Of this, most of it is found (52%) in growing vegetation and the rest in grapes (28%) and permanent parts of the plant (20%).

From the harvest period until lethargy, the distribution of nitrogen within the plant is differentiated and shifted to its permanent parts. During this period only 6% of the total nitrogen in the plant corresponds to what was added in early summer, and is found 78% in the roots and 22% in the remaining permanent parts.

The addition of nitrogen after the previous season’s harvest was also investigated. It was found that 60% of the nitrogen reserves of the plant at the beginning of bud growth come from the nitrogen absorbed during the post-harvest period and that 1/4 of the nitrogen reserves of the plant are used until the end of flowering, while by the end of the harvest 50% of the nitrogen reserves available during bud development,  were used (Conradie 1980,1991,1992c).

In general, three main periods of time during which nitrogen is added are used in production:

When expanding the eyes ,

after flowering and

after harvest.

Data collected during experimental work on the effect of application time and the amount of nitrogen added support the correctness of the above nitrogen addition times.

The determination of the amount of nitrogen to be added to each application is a more complex matter, but the finding that 60% of the nitrogen reserves of the plant during the bud growth period comes from what is added after harvest highlights the importance of the applied nitrogen fertilization program after harvest.