Commonly used fertilizers are mainly composed of three main minerals: nitrogen (N), phosphorus (P) and potassium (K).
Each of these elements has a particular function for the development of the plant: nitrogen is useful for favoring the development of vegetation in general, and for the production of chlorophyll; phosphorus promotes the development of the root system and stimulates photosynthesis; potassium stimulates photosynthesis and sugar production, promotes the color of flowers and fruits and the taste of sugary fruits.
In every season of the year the plants need these three main elements, even if in every season they need these macroelements in a different way.
Generally during the spring months all the plants need nitrogen, to favor the development of new shoots and branches, stem and leaves; only succulent plants and cacti do not particularly like excess nitrogen, therefore it is advisable to always use low nitrogen fertilizer with these plants.
During the autumn months, starting from the end of the summer, it is advisable instead
use fertilizers with a higher phosphorus content, especially with regard to plants that have recently been planted or repotted, in order to favor the rapid and healthy development of the root system.
During the winter months it is generally advisable to avoid fertilizing, since most of the plants are in vegetative rest, and therefore the mineral salts deposited in the soil would accumulate, favoring the development of some pathologies.
Summer fertilizations: During the summer
In summer, when the sun is warmer and more scorching, it is good to avoid fertilizing, or in any case to reduce it; this is because when the heat is very intense and the climate is dry, most of the plants enter a vegetative semiriposo; in any case, during the flowering and fruit production periods, the plants need a good amount of potassium, which favors the coloring of the flowers and the taste of the fruits.
Generally the premixed fertilizers for flowering plants are particularly rich in potassium, so they are very suitable for use during the months of May / June and August, until September; during the month of July, and in the hottest weeks of August, it is better to avoid fertilizing.