Fertigation: a technique with good advantages for the crop and the producer

Fertigation is a technique that consists of applying fertilizers together with irrigation water. Find out more about the advantages of this management for both the crop and the farmer.

Fertigation is a technique in which fertilizers are applied, which are nutrients for plants, together with the irrigation water, accelerating the cycle of nutrients used: they reach the soil in smaller and more frequent quantities, in addition to being already diluted in the irrigation water. This way, they are readily available for absorption by the plant.

Another important characteristic of fertigation is the possibility that the farmer has to correct the supply of nutrients to the plants throughout the growing season, since with this management it is possible to carry out a greater number of applications throughout the harvest. “It is a more balanced form of fertilization, which makes it possible to calculate and also adjust the nutrients needed for a given crop according to its phenological phase, which helps to obtain greater quality and productivity”, explains specialist Lucas Muraoka, from Yara Brazil. 

As there is no application of large doses of fertilizers at once, spikes in acidity or salinity in the soil are avoided. In this way, a better environment is created for the development of beneficial microorganisms in the soil. “As a rule, the fertigated cultivation system tends to result in greater productivity due to its benefits. With greater crop productivity, a smaller area is needed to produce the same amount of food compared to lower technology cultivation systems. In this way, fertigation contributes to a reduced need for land destined for agriculture”, explains the specialist.

The appropriate use of fertigation, therefore, is also very positive in terms of sustainability, as it considerably saves the use of natural resources. We can mention the greater efficiency in the use of water and nutrients by crops, the reduction of climate risk due to less dependence on rain, the provision of balanced nutrition in the correct quantities for plants due to the greater splitting of fertilization (which, in turn, it tends to result in greater productivity and crop quality), savings in labor, reduced operating costs and greater soil conservation by reducing the traffic of people and machinery in the area. 

Fertigation systems

In Brazil, there are four main irrigation systems: drip, micro sprinkler, central pivot and conventional sprinkler. 

The choice of technique must take into account several factors, such as the farmer's financial resources, physical properties of the soil, topography, area size, climate, crop management, water resources, among others. “Fertirrigation is a technique that brings many benefits, but knowledge is needed to get the best out of it.”

Fertigation for perennial crops

Much attention is needed when managing fertigation in perennial crops, such as coffee, to avoid severe impacts on the root environment and soil, which are accumulated over the years of cultivation. The main onesThe negative impacts are soil acidification and/or salinization and nutritional imbalances. “This damage can be quite significant, as it affects the absorption of water and nutrients by the plant, in addition to root development and, consequently, the development of the crop”, explains Muraoka.

Currently, the largest market for fertigated coffee is Conilon, grown mainly in the state of Espírito Santo and also in the southern region of Bahia. One of the region's biggest challenges is water availability, followed by the combination of rising production costs and stagnant coffee prices. “The state went through a severe water crisis from 2014 to 2016, bringing difficulties to several rural producers in the region. In view of this, the search for high-efficiency irrigation systems, especially drip, has increased and, even, with financial institutions prioritizing agricultural financing for crops with irrigation projects in this modality”, reveals Muraoka.

Other perennial crops, such as mango and citrus, can also achieve good results using fertigation. Mango, for example, is produced mainly in the states of Pernambuco and Bahia, regions that naturally have a semi-arid climate, with low rainfall. Therefore, water use efficiency is a premise for crops in these areas. 

Citrus, grown mainly in the state of São Paulo, is divided into two main production classes. Table citrus is for the end consumer and focuses on quality, beauty, flavor and durability, while the industry's main focus is on achieving high productivity. “Even so, the crop still has relatively low adherence to fertigation, due to the initial investments, which can be high, and also the knowledge necessary to carry out adequate management of the fertigated crop”, comments Muraoka.

Unlike perennial crops, crops with fast cycles, such as vegetables, have less room for error and the response time for rural producers is even shorter. 
“As crops with high costs and risks, adequate nutritional care at each phenological stage is essential for good results in productivity, quality and, consequently, profitability for rural producers”, he explains. 

With increasing production costs and difficulty in finding qualified labor, a correctly managed fertigation system meets the great demands of rural producers. Despite the relatively high initial investment, it reduces the need for labor and time used for fertilization, reducing operating costs. In the agronomic aspect, the benefits are many, with the main focus on nutritional balance and supply of nutrients according to the plant's demands, positively impacting productivity.