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Post-harvest fertilization in super-intensive crops such as olive trees, fruit trees or almond trees, as well as grapes (table and wine grapes) is a necessary process at the end of a campaign. Once harvesting is over trees are left “exhausted”, having put all their nutritional resources into producing their fruit. It is important to bear in mind that in the months prior, the plant has gone through phases with high energy demands, especially during flowering, fruit set and fruit development. 

Once harvesting is over there is a hiatus in the tree’s activity while it prepares to mobilise nutrients for bud burst and producing leaves that will enable it to start the following campaign. Between harvesting and leaf fall or vegetative dormancy, the plant must accumulate the necessary reserves to initiate the next cycle. It is at this point where Radisei, a Seipasa root biostimulant with microorganisms, fulfils all of these requirements and is also a product that is registered with the Ministry of Agriculture.

Although the application of post-harvest nutrients is a determining factor, it is not always taken into account by farmers.  Harvesting is the climax of a year of intensive work and once it is over the tree enters into a period relaxation, of vegetative dormancy. 

Post-harvest fertilization in fruit trees

In the specific case of fruit trees, they build up their reserves between the end of the summer and the beginning of the autumn season. During this period trees accumulate nitrogen and other nutrients such as phosphorus or potassium that will serve as reserves for the following biological cycle. Soil nutrients must be available, and the plant must be able to absorb them over this period, and this is the function that Radisei performs in just one application via fertigation. 

Post-harvest fertilization in fruit trees functions the same way as it does for vines, almond trees and olive trees: the tree stores nitrogen in the plant which is conveyed via the leaves to the woody part, as “petrol” to start future budding, flowering and fruit set. Most of the nutrients that the tree uses during its development are obtained at this prior stage, which means that optimising this process as much as possible is very important.

At the onset of bud burst the tree depends on the reserves it has built up. If the tree has few or insufficient reserves it will not stop growing but it will direct its energies mainly towards essential processes and this can affect the development of the rest of its organs. 

In order to generate and guarantee reserves after harvesting in vines and super-intensive crops such as olive trees, almond trees or fruit trees, application of Radisei is recommended as it encourages the absorption and rapid availability of key nutrients. Radisei generates a more extensive, more efficient root structure with more absorbent hairs, ready for the next campaign, which guarantees a robust start for trees in their next biological cycle.  

Radisei: release of essential micronutrients

Radisei is developed from Seipasa’s exclusive SEIBS23 Bacillus subtilis that acts on the soil’s biological processes and on the plant’s root system to release essential micro and macronutrients and ensure a high-quality final production.

The differentiating action of the exclusive SEIBS23 strain of Bacillus subtilis means that Radisei carries out high metabolic activity and it engages perfectly with roots which increases solubilisation of potassium and iron as well as encouraging the fixation of atmospheric nitrogen. These are elements that, as we have seen, play a fundamental role in generating post-harvest reserves in grapes, fruit trees and in super-intensive crops such as olive and almond trees. All of this enables soil activation and makes the nutrients that are crucial in this process of building up reserves available to plants.

Radisei is a product registered with the Spanish Ministry of Agriculture, Fisheries and Food. Recommended post-harvest use: a single application of 2.5 to 5 kg/ha, applied just after harvest end, when the plant has active leaves.