Olive Grove Fertilization
The ability of the olive, not only to survive, but also to produce normally in sloping, barren and marginal soils very often leads us to underestimate the nutritional requirements and degrade the importance of fertilization in this crop. The very irregular production (parenchyma) makes us think that in this species there are “maintenance” mechanisms that prevent the plants from normally differentiating the flowering buds when the possibilities are limited. Low nutritional rates cause at the same time, stop and block the mechanisms of differentiation of the newly formed eyes, resulting in the postponement of development for the next year. In order for a plant to produce at a normal rate, it must grow, maintain at the proper level the stored substances and at the same time ripen the fruits, therefore its energy requirements are quite high. This leads to the conclusion that the olive, in order to produce normally, should be considered in terms of nutritional requirements, a plant with the same nutritional requirements as the other fruiting ones. Various analyzes are used to determine the applied fertilization elements and the productive margins of the variety in the specific area should be known.The analyzes that are usually needed to determine the nutritional requirements are the soil and the leaf diagnostics. Soil analysis is necessary to identify any limiting factors (pH, salinity, IAC) or percentages of available elements (usually cations), while it is of little use in designing and planning a fertilization plan, because available percentages are affected. by exogenous factors (temperature, available water percentages, etc.). The analysis of the percentages of some inorganic elements in the leaves (N, P, K, Ca, Mg) offers indications of greater agronomic utility. The biggest caveat in this method is that the specific relationships between the composition of the leaves at a given time and the condition of the whole plant are not known, while even further is the relationship between the nutritional status of the leaves and the yield. Indeed, the leaves represent a small percentage of about 3% of the total dry matter of a plant, while the large amount of stored substances is located and managed in the trunk, arms and main roots and another significant amount is transported by the buds and the smaller growing production control processes can be considered only the “second component” of development.