What is Fertigation?

Fertigation is the technique of supplying dissolved fertilizer to crops through an (micro-) irrigation system by the use of T-tape, drippers, micro-jet or sprinklers. When combined with an efficient irrigation system both nutrients and water can be managed to obtain the maximum possible yield of marketable production from a given quantity of these inputs. Therefore fertilization (fertigation) is an added benefit of irrigation. Today, fertilizer solutions and suspensions are routinely injected into irrigation systems via calibrated injection pumps that insure precision over both space and time. The availability of high quality water is necessary for successful fertigation in order to avoid any problems with clogging of orifices due to precipitation of fertilizers.

Sprinkler system

Fertigation has increased dramatically in recent times, particularly for sprinkler, center pivot and drip systems. For drip systems, the expansion is mostly in horticultural and high value crops. In agricultural areas with declining water supplies, drip systems have also increased. Fertigation has a key role in high quality, high value, economic crop production. Fertigation will continue to grow since such systems result in less water consumption and better uniformity of distribution.

Fertigation, particularly with drip irrigation, restricts the development of the root system in comparison to conventional broadcast fertilizer application. In order to encourage root growth or to maintain better root volume, the addition of BIOSTIMULANTS like WUXAL Aminoplant, WUXAL Ascofol, WUXAL Terradrin can be beneficial.

Agriculture

Benefits to Crop and Environment

By changing the nutrient ratio of the fertilizer solution fertigation can be perfectly matched to the nutrient demand of specific crop stages of the crop. This is an excellent prerequisite for yield increase and quality improvement, particularly of cash crops. As fertigation, particularly with drip irrigation, involves the frequent or continuous application of small nutrient amounts directly into the root system, the risk of nutrient leaching, even in sandy soils, is very low in comparison to standard soil fertilization systems. Soil compaction is avoided due to the fact that equipment never enters the field. Fertigation is particularly efficient in dry areas or such with less frequent rains. In comparison, in rainy areas or seasons, slow and controlled release fertilizers (AZOLON, PLANTACOTE) are definitely the most efficient products or should be at least applied in combination with fertigation.

FERTISAL – Product Quality Requirements

Fertilizers for fertigation, particularly water-soluble compound fertilizers, must meet specific quality requirements. The nutrients should be pure and fully available for plant absorption and the product fully water-soluble in order to avoid any problems of clogging of orifices. The micronutrients should be chelated (EDTA / EDDHA). The nutrient ratio, particularly the NPK-ratio should meet the specific requirements of crops and growth periods.

The product should be safe, the pH optimal for the soil conditions (i.e. acid for application in alkaline soils) and compatible with other fertilizers. High-guality FERTISAL fertilizers all meet such physical, chemical and agronomical requirements.

Soil Chelates

Benefits of Soil Chelates

Soil-applied or fertigated metal-chelates are reaction products of micronutrients like copper, iron, zinc and manganese with strong chelating agent molecules like EDDHA, DTPA or EDTA. The word "chelate" is from the greek "chele" and means crab claw. This means that a chelate keeps a micronutrient tightly in its grib. The micronutrient metal remains stable and soluble and cannot react with anions like phosphate to unsoluble compounds.

Generally, chelates maintain soil micronutrient availability for root absorption. Particularly in alkaline-carbonate soils, chelated micronutrients are the only way to supply sufficient micronutrients to the crop via the root system.

Metal chelates derived from EDTA (Fe, Mn, Zn and Cu) and from EDDHA in relation to Fe in alkaline soils are the products of choice under soil conditions limiting micronutrient availability. There are no stable chelates of B and Mo.

Root absorption

Quality Requirements

As to zinc, manganese and copper, EDTA-chelates are among the most stable chelates for alkaline soils where micronutrients with the exception of molybdenum are easily fixed to unsoluble forms not available to the plant (CRESCAL Zn, CRESCAL Polymicro).
In relation to iron, EDDHA is the strongest and most efficient chelate for application to alkaline soils (CRESCAL Fe, CRESCAL Polymicro). CRESCAL chelates evidence a very high solubility and stability under high soil pH conditions. The micronutrients contained in CRESCAL chelates are protected from adsorption to soil particles (inactivation) and from too rapid microbial degradation.
CRESCAL chelates are rapidly available to the plant and have a remarkable residual effect during the growing season as well.
CRESCAL chelates are excellent materials for being applied in modern fertigation and hydroponic systems.