Fruit and Vegetables

Spring fertilization


Question: spring fertilization


I have various fruit trees from the cherry trees, apple trees, pears, plums, apricots, noses, I would like to know if in this period that the flowers are blossoming what kind of fertilizer should be used to improve the quality of the fruits, I await your answer thanks.

Answer: spring fertilization


Dear Alberigo,
the fertilizers that we find on the market contain different mineral salts, which are necessary for the plants for a correct, harmonious and healthy development; in the fertilizer in general there are three macroelements, or three minerals that are used by plants in large quantities, and therefore are contained in large quantities even in the fertilizer.
The three elements are Nitrogen (N = Natrium), Phosphorus (P = Phosphorum), and Potassium (K = Kalium); on fertilizer bottles of any kind, you can find the quantity of these minerals contained in the fertilizer itself, in particular you can find the concentration, expressed in three numbers; for example on the bottle of a universal fertilizer you will find something like: NPK 15:15:15, or even 15-15-15; this means that 15% of the fertilizer consists of nitrogen, 15% phosphorus and 15% potassium. Later you will also see other symbols, such as B (Boro), Mg (Magnesium), Fe (Iron), these are microelements, the plant needs them, but to a much lesser degree.
Nitrogen, contained in large quantities also in manure, is the macro-fertilizer useful especially at the end of winter, because it is used by plants to produce new tissues and sprouts; Phosphorus, on the other hand, is the most useful element to improve the development of the root system, and therefore it should be used in particular in late summer and autumn.
The most useful mineral for flowers and fruits is potassium (K), and in fact a good fertilizer for fruit or flowering plants should carry an inscription of this type: NPK 15-20-30, or should contain about twice as much potassium compared to the amount of nitrogen.
I therefore advise you to look for a fertilizer that contains a good amount of potassium, avoiding universal fertilizers, because during flowering and fruiting the plants do not need as much nitrogen, so this would remain in the soil, later washed away by rain and watering, would continue towards the aquifers, rivers and the sea, becoming a strong source of pollution (we all remember, to give just one example, the problems of mucilage present in the Po delta, caused largely by the nitrogen of the crops, used in excessive quantity, its function of fertilizer that stimulates the shoots and the production of leaves also works for algae).
In addition to potassium, very useful for fruit ripening, therefore to be used in the orchard and in the vegetable garden, a fertilizer rich in Magnesium (Mg), which works in conjunction with potassium, also improving flavor, color and size of the fruit; I assure you that in the nursery you can find a fertilizer based on potassium and magnesium, to be used about a couple of times, during the fruiting period.