At the same time as the first side shoots appear, pruning should take place. This consists in the elimination of some of the aforementioned shoots which in turn will improve the ventilation of the plant. Due to the use of pruning techniques, the number of stems per plant will be determined. Between 1 or 2 stems are frequently left after pruning, although with respect to cherry tomato plants, 3 or even 4 stems may be left on the plant. With the incorporation of crop training the plant is kept upright which improves the general ventilation of the plant and provides optimum conditions for plant growth and the undertaking of cultivation procedures. Approximately 30 days after transplanting, flowering begins. The first flower cluster develops once the plant has three true leaves in the leaf axils. The rest of the inflorescents will be located every 2or 3 leaves up to the growing tip of the plant. Another important task is de-suckering, which consists in the elimination of axil shoots and is carried out weekly throughout summer and autumn, and every 10-15 days in winter. In order to gain optimum benefits from pollenization, a beehive of Bombus Terrestris should be placed inside the greenhouse, at the beginning of flowering. Approximately one and a half months after transplanting, ovary development commences which leads to fruit being formed. From this moment onwards and depending upon the stage of advancement of the crop, the water requirements of the plant will increase; therefore watering must be adjusted in line with the evapotranspiration of the crop. During the fruit development stage, brusque changes in humidity levels should be avoided as diseases could appear such as the splitting or cracking of the fruit, amongst others. The growth period of the fruit, from flowering to ripening, will depend upon crop conditions but will vary generally between 45 to 60 days. Under normal conditions, the main stems are trimmed once the plant has between 6 to 10 branches. In this way the plant will produce both larger and earlier fruit. With the view of facilitating ventilation and improving fruit colour, de-leafing is undertaken which consists in eliminating both the old and diseased leaves. This task should be carried out extremely carefully in order not to remove any of the leaves acting as a source of photoassimilates to the inflorescents and the fruit. With regard to vine tomatoes, the trimming of the inflorescents and the thinning out of the fruit is important. This takes place with a view to equalizing and increasing the size of the fruit, in order to improve quality. With respect to nutrition, the importance of Nitrogen/Potassium ratios varies throughout the growth cycle. These are a 1/1 ratio from transplanting to flowering and a 1/2 or even a 1/3 ratio during fruit picking. Phosphorous also plays an important role during the stages of root taking and flowering. This is due to the fact that is plays a vital part as regards root formation, flower size and the regulation of pH. Another fundamental element related to tomato nutrition is calcium, which facilitates the prevention of apical necrosis or peseta. Fruit picking may be carried out at different stages of ripening depending upon market requirements. It is advisable to pick fruit in the early morning, and then, if possible, to refrigerate the fruit.