The role of fertilizers is undeniable in the response of the plant, and even more so when it comes to crops intended for production and from which an economic return is obtained.
Today, the list of raw materials to be used is very long, and we can initially classify them as fertilizer for conventional farming and also for ecological agriculture.
To dive a little deeper into this world, it is interesting to know the types of fertilizer depending on the stage of cultivation. We will mainly differentiate the following stages of a plant:
- grafting/rooting
- vegetative development
- Flowering and fruit set (not in leafy crops)
- fruit fattening
- Maturation and pre-harvest
Contents
List of fertilizers according to the stage of your crop
Transplantation and root development
The transplanting phase is distinguished by having a small plant that is quite sensitive to atmospheric phenomena and the salinity of fertilizers.
As the root system is very small, the fertilizer input must be very low, giving priority to elements such as nitrogen and phosphorus.
We recommend that you do not add fertilizers with a high salt content (of inorganic origin) until 7-15 days after transplant.
Recommended inorganic fertilizers
- NPK 13-40-13 or similar, with high phosphorus content.
- Ammonium nitrate (N 34.5%).
Organic fertilizers and biostimulants
We can stimulate root development with the following fertilizers of organic origin, applied in irrigation.
- Amino acids (3-5 ml/L of water)
- Humic and fulvic acids (2-3 ml/L of water)
- Seaweed extracts (2-3 ml/L of water) as Ecklonia Maxima.
Growth and development of shoots and leaves
At this stage, rapid development of the plant is sought, especially of the aerial part. We seek to generate new shoots and leaves to build good plant architecture, before the emergence of buds and flowers. Therefore, it is recommended to use so-called growth fertilizers.
Recommended inorganic fertilizers
- NPK 15-5-5 or similar, high in nitrogen.
- Calcium nitrate, to provide calcium.
- Micronutrients, especially iron (in chelate form).
Organic fertilizers and biostimulants
We can stimulate root development with the following fertilizers of organic origin, applied by leaf.
- Amino acids (2-3 ml/L of water)
- Seaweed extracts (2 ml/L of water)
In fertigation, we can continue to add organic matter to promote greater development of roots and microorganisms.
Bloom

For flowering to occur, the plant must synthesize more carbon compounds (such as sugars and amino acids). For this reason, nitrogen tends to be reduced to prevent the plant from continuing to have a vegetative attitude.
Elements like phosphorus, potassium, and boron can help promote the production and transport of these produced sugars or photoassimilates. Therefore, flowering fertilizers generally contain more carbon-rich organic elements.
Recommended inorganic fertilizers
- NPK 5-10-10 or similar, with higher phosphorus and potassium content
- Micronutrient complexes, with a particular focus on boron and molybdenum.
Organic fertilizers and biostimulants
Natural seaweed complexes (with sugars, vitamins and natural phytohormones) or amino acids, usually applied in foliar application
- Seaweed extracts (2 ml/L of water) as Ecklonia Maxima.
- Amino acids (2-3 ml/L of water)
Fruit fattening or leaf development
In fruit fattening or when we are looking for a higher concentration of sugars or oil yield, potassium has a particular impact at this stage.
Root development should also be monitored, as fruits consume many resources and roots can be compromised by not receiving enough photoassimilates or sugars produced by the leaves.
Recommended inorganic fertilizers
- NPK 15-5-20 or similar ratio.
- Micronutrient complexes
- calcium nitrate
Organic fertilizers and biostimulants
Stimulants can be used for cell fattening or to lengthen the volume of the leaves and start the production of essential or fatty oils.
- Seaweed extracts (2 ml/L of water) as Gnarled Ascophyllum.
- Amino acids (2-3 ml/L of water)
Maturation
In this phase, the supply of nitrogen is considerably reduced, with a particular incidence of potassium as a final element. It is also advisable to add a little phosphorus, because it participates in the energy supply of the plant.
Recommended inorganic fertilizers
Organic fertilizers and biostimulants
Certain extracts of seaweed and microalgae provide components from the coloring of fruits or make it possible to acquire sugars and the optimal final oil for the harvest.