Controlled release fertilizers

Controlled Release Fertilizers (CRF) such as ICL’s Agroblen and Agromaster are fertilizers in which the nutrient release is controlled, meeting the stated release rate of nutrient and the stated release time at a specified temperature. CRF plays a key role in improving yield, reducing nutrient losses and simplifying fertilizer applications. 

What distinguishes Controlled Release from Conventional Fertilizers? 

CRF is considered the fertilizer technology with the highest nutrient use efficiency. It is widely recognized that mineral fertilizers, including CRF, are responsible for feeding about half of the world’s population. Conventional fertilizers dissolve in the soil immediately after application, only providing nutrition for a short period of time. Multiple fertilizer applications are necessary to ensure that your crop gets the nutrition it needs. Multiple applications can also be practically complex for big farms, costly, and, as we know from recent studies, increase problems with soil compaction. Based on independent research with ICL CRF technologies, and depending on circumstances in cultivation, CRFs such as Agroblen and Agromaster can significantly reduce:  

  • Total fertilizer use 
  • Leaching 
  • Denitrification 
  • Volatilization 

What differentiates Slow and Controlled Release Fertilizers? 

It is important to note that not all CRF are the same, and often the term CRF is – incorrectly – used when one means Slow Release Fertilizers (SRF). Let’s look at the official definitions of these two types of fertilizers: CRF: “A fertilizer in which nutrient release is controlled, meeting the stated release rate of nutrient and the stated release time at a specified temperature.” (ISO 8157:2015) SRF: “A fertilizer of which, by hydrolysis and/or by biodegradation and/or by limited solubility, the nutrients available to plants is spread over a period of time, when compared to a ‘reference soluble’ product e.g. ammonium sulphate, ammonium nitrate and urea.” (ISO 8517:2015). So, the nutrient release mechanism for the two fertilizers is completely different. SRFs are minerals that take a certain time to dissolve or to release their nutrients. CRF require a good quality coating and a consistent manufacturing process. While SRFs nutrient release is influenced by temperature, water, soil pH, and microorganisms, CRF are only influenced by temperature and water. 

How long do Controlled Release Fertilizers continue to release nutrients? 

Thanks to their special coatings, CRF granules release their nutrients gradually over an extended time. Depending on a CRF product’s longevity, nutrient release takes several weeks up to many months. Some of the key benefits of ICL’s Agroblen and Agromaster are: 

  • Higher nutrient efficiency through reduced losses 
  • Higher or equal yield with less mineral input due to continual feeding 
  • Less applications = less costs 
  • Better for the environment due to reduced leaching 
  • Enhanced crop uniformity thanks to controlled nutrition 
  • Greater protection against early season “salt stress” 
  • Enhanced crop uniformity thanks to controlled nutrition 


Agroblen is the top brand in ICL's controlled release fertilizer portfolio. Agroblen contains a 100% coated NPK granule and is available in various longevities.

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Your fertilizer program must be superior to maintain a secure and profitable business. For this reason, ICL created Agromaster - a product that is superior in performance, but simple to use.

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