Control Release Fertilizers

Control Release Fertilizer gradually releases nutrients into the soil within a given period, measured in months, in a controlled way.


Simonis Fertilizers B.V. also offers a range of controlled release fertilizers (CRFs).

The difference between the common mineral fertilizers and the Controlled Release Fertilizers, is mainly the coating. Due to a specific coating, CRFs release the nutrients to the plant more gradually than common mineral fertilizers. The positive effect is a better, more even, plant growth, and therefore less susceptible to damage or diseases and higher yields. Another advantage is less leaching of minerals.

With CFRs it is possible to fertilize during the whole growth season, from a cycle of six weeks till eighteen months, depending on the time it takes each CRF granule to release the nutrients inside, under the climatical circumstances. Each particular crop calls for a different kind of CFR, taking into thorough account, the climate and soil type.

CFRs are available with various types of coatings. From 100% coated NPK with trace elements, to partially coated ‘N and/or P and/or K’-blends, with or without trace elements. The different types ofcoating available are: resin, sulphate (with a higher initial release), or a polymer (polyethylene) coating. Each coating has its own characteristics. The type of coating determines the speed of the release of the various minerals. Besides the type of coating, other factors contribute to the release of fertilizers; the shape and size of the fertilizer, the moisture content and soil temperature, and its microbial activity.


The fertilizers can be packed in either standard neutral, or simple labelled WPP/PE or PE-bags of 25-Kg. It is also possible to get your own custom-made pre-printed PE, or WPP/PE (laminated) bag, at a minimum quantity of approx. 10,000 bags.

Please contact us for more information on our range of Controlled Release Fertilizers.