One of the main objectives of the LIFE Steppes of La Mancha project is to optimize fertilizing in cultivated lands in the SPAs where the project takes place. This is conducive not only to an improvement in the environment which stops the loss of steppe birds, but also to savings to the farmers’ investment costs. For this reason, it’s important to know the nutrient content of the soil and how each element that fertilizes the crops works.

To choose the right manure and different fertilization products in a constantly evolving and vast market, it’s best to first talk about the elements and the role they play in our crops.

We need to understand the differences between some simple but very important terms:

  • MACRO ELEMENT: Every plant in its vegetative cycle requires nutritional elements for a favorable development and good production.
    • Macro elements are considered essential elements, and are divided into primary (nitrogen, phosphorus, and potassium) and secondary (sulphur, calcium, and magnesium)
  • MICRO ELEMENT: also known as minor elements, we can mention: boron, zinc, copper, manganese, iron, molybdenum, etc.

Throughout the next few weeks, we’ll briefly explain the way in which these elements affect our crops, the most important elements, as well as their presence and deficiency.



Nitrogen Cycle. Modified from Johann Dréo / CC BY SA 3.0 (Wikipedia)


  • Fundamental constituent of nucleic acids, proteins, enzymes, coenzymes, and chlorophyll.
  • Responsible for plants’ green color
  • Being a plastic element, nitrogen favors cellular multiplication and the photosynthesis of chlorophyll, resulting in the formation of sugars and plant growth.
  • Regulates the use of carbohydrates and controls cell turgor.
  • Increases protein content in vegetables, fruits, and fodder crops.

Nitrogen deficiencies exhibit easily-detectable acropetal symptoms, which means the development of this deficiency goes from the base to the apex of the plant, such as limited growth of the plant and its roots, small and discolored leaves (chlorosis usually begins in the oldest). If the deficiency is very strong, fruits fall, ovaries become sterile, and production decreases.

This deficiency can happen due to excessively alkaline, acid, saline, and sandy soils, low organic matter, or leaching.

Excessive amounts of nitrogen can also lead to problems, such as toxicity in leafy vegetables. The vegetative cycle lengthens, triggering increased leaf development which will logically increase water consumption. This decreases resistance to disease and atmospheric agents, worsening the quality of our fruits.



Phosphorus cycle. Modified from Bonniemf / CC BY SA 3.0 (Wikipedia)


  • Constituent of nucleic acids, phospholipids, ATP, coenzymes, and molecules used for the transfer and accumulation of chemical energy.

  • Takes part in the synthesis of amino acids and proteins as well as in the metabolism of carbohydrates.

  • Gives rise to a sudden and vigorous vegetative beginning

  • Stimulates flowering and seed formation

  • Anticipates the ripening of crops

  • Favors the development and growth of the roots

  • Increases resistance to illness

  • Activates the Rhizobium, which facilitates atmospheric nitrogen fixation 

  • Favors lignification

  • It’s necessary for translating energy to the interior of the plants

With phosphorus deficiencies, the symptomatology is acropetal, with limited development of vegetation with thin tissues, not very consistent and lignifies, few and small flowers. The coloration of the leaves becomes green-blue, dark with limited root growth.

This deficiency can happen due to excess Ca, Fe, or Al, as well as soils that are too alkaline, acid, clayey, or saline, and the lack of organic matter.

The excess of phosphorus doesn’t produce toxicities, but it induces the plant’s pollination process and early ripening, as well as producing Fe and Zn deficiencies and reducing production.


… shortly, we’ll discuss more elements!!!


Want to learn about other actions of the LIFE project? Visit Actions LIFE Steppes of La Mancha

Download the dissemination material of LIFE Steppes of La Mancha

Learn about the farmers who work in favor of steppe bird populations.