April pruning is called Foundation Pruning because the foundation of the next crop is laid during this period by developing fruitful canes and food storage in the vine. After a period of rest, the vines are pruned to a single bud, helping in vegetative growth.
Potential yield in a harvest year is determined during April pruning and is influenced by nutrient levels at the time of fruit bud initiation and differentiation.
The post-harvest period is an important time for restoration of carbohydrate and mineral nutrient reserves. Nutrient and carbohydrate reserves for grape vines are essential for vine health and performance. Post-harvest nutrient application increases the stored nutrient status of vines, reducing potential deficiencies from bud break up to the end of flowering.
April pruning is a critical period to apply soil based and foliar fertilisers as the vines are actively translocating nutrients from the leaves to the canes and the trunk of the vines to store these elements as a carbohydrate source. This is also a period of active root growth and is important to apply fertilisers into the soil.
Balanced nutrition with all essential nutrients is beneficial as it will supply the vines will all elements required for carbohydrate assimilation and metabolic reactions which occur when the vines are in the carbohydrate storing mode.
Storage of nutrients during the post-harvest period is due to both re-translocation from the leaves, particularly for N and P, and further root uptake from the soil.
Yara Crop Nutrition Program for April pruning gives complete and balanced nutrition to lay a strong foundation for your main crop.