For the production of grafted plants, the starting point is the olive tree kernels, which represent the propagation material and from which the “seedlings” (olive trees commonly called “wild”) on which grafting will be practiced are obtained..
As regards the choice of olive tree varieties from which to take the stones, the nursery experience gives precise and detailed information, as well as the most appropriate criteria and precautions to be taken at this stage.
Using special stoning machines, the stones are separated from the pulp of the olives and then carefully washed and cleaned of oily residues. Carefully dried, they are kept lying down in perfectly dry, fresh and well ventilated rooms until the time of the pre-sowing treatments. At the end of July, about 3 weeks before sowing, the stones undergo a moisturising treatment that will promote germination in the seedbed.
The seeds are sown at the end of August in specially prepared areas, using suitable substrates.
For sowing, 1.5-2 kg of seed per square metre of seedbed is used in relation to the size of the kernel. The stones are spread evenly over the surface of the seedbed and covered with a uniform layer of soil. The seedbed is then darkened with felt sheets placed on special metal frames.
The care of the seedbed after sowing is simple but constant and cannot be neglected. The stones begin to germinate at the end of September – beginning of October. At the end of December an average of 75-80% of them have germinated, although the end of germination is considered in January.
In the nestaio plot, where the seedlings will grow, the soil is prepared appropriately. The transplanting of seedlings takes place in spring in the months of April-May.
The seedlings with 6-8 leaves (3-4 boxes) are gently removed from the seedbed.
The planting in the nestaium is carried out in regular rows, placing the plants in squares at a distance of about 8 – 10 centimetres; in this way a planting density of about 130 plants/sqm is achieved.
Once the transplanting operations have been completed, the seedlings need to receive adequate care, in order to obtain plants that are particularly developed and suitable for grafting.(photo C)