Superior Performance with Controlled Release Fertilisers

Controlled Release Fertilisers – superior proven performance for a sustainable future

February 28, 2024
2 mins
Ronald Clemens
CRF Marketing & Portfolio Manager

Fertilisers are a crucial part of modern agriculture. In the same way that we need nutrients to grow, plants also have nutritional needs – typically requiring more than 14 essential nutrients for healthy crop growth. But it is not just a case of selecting the right nutrient combination, it’s also important to consider the type of fertiliser. Controlled-release fertilisers bring many benefits that make them ideal for ensuring crops have sufficient nutrient availability at the right time to produce the quantity and quality of harvests that we all rely on.

Comparing Fertiliser Types

While conventional fertilisers can supply the nutrients crops need, they often result in nutrients being lost to the environment through leaching, volatilisation, denitrification, runoff, and soil fixation, reducing the efficiency of the fertiliser application.

Enhanced-efficiency fertilisers are designed to specifically address the issue of nutrient loss.

There are three types of enhanced-efficiency fertilisers in use today: slow-release fertilisers, stabilized nitrogen fertilisers, and controlled-release fertilisers.

Slow Release Fertilisers

Slow-release fertilisers provide nutrient availability over a prolonged period, generally up to 6 weeks. This availability depends on many factors, including the temperature of the soil, the moisture, the soil pH, and microbial activity in the soil.

Slow-release technology can prevent nutrient losses and is successfully used for professional turf, lawns, gardens, and landscaping. But, when dealing with crops with longer growth cycles or specific nutrient requirements, the number of factors influencing the nutrient release and the period of availability means that the effectiveness of slow-release fertilisers is debatable.

Stabilised Nitrogen Fertilisers

Stabilised nitrogen fertilisers are designed with the specific goal of preventing nitrogen losses caused by volatilisation and leaching. As the name suggests, these stabilised nitrogen fertilisers keep the nitrogen in its original chemical form for a longer period of time.

This technology can mitigate N losses, but the effectiveness of stabilised nitrogen fertilisers is influenced by soil type, pH, and temperature. This means that high temperatures and high or low pH soils can reduce the effectiveness of these fertilisers. Sorption to clay particles and organic matter or immobilisation by non-target microorganisms can also decrease their efficiency. Furthermore, blending stabilised nitrogen with phosphate fertilisers may result in chemical interactions that reduce the stability of these nitrogen fertilisers.

Controlled Release Fertilisers

Controlled Release Fertilisers are more versatile and provide optimum nutrient levels throughout the crops’ entire growing cycle, with a wide range of longevities, from 1 month up to 1.5 years. These are the most versatile fertilisers to nourish soil-grown crops.

ICL’s coated CRFs consist of a nutrient core protected by two layers of fully biodegradable coatings. The nutrients inside are dissolved by soil moisture and released into the root zone.

What makes CRFs stand out from the other types of enhanced-efficiency fertilisers is the release process which is steered by soil temperature alone and is totally independent of soil type, pH, or other factors. This means the release rate is more predictable and better matched to the needs of the growing crop.

Compared to conventional urea, controlled-release fertilisers reduce all types of nitrogen losses and improve the crop’s nutrient use efficiency. CRFs reduce N losses from leaching and volatilisation by up to 60% and reduce losses from denitrification by over 10%.

An 80% increase in Nutrient Use Efficiency means application rates can be reduced by up to 30%, and farmers can reduce the number of applications, saving on labour and resources.

These benefits, demonstrated by independent research, clearly show why controlled-release fertilisers set the standard among enhanced-efficiency fertilisers, serving as a superior and essential tool for modern agriculture.