As farmers are put under more pressure to work in a sustainable manner, those looking to improve their environmental credentials, while boosting yields, should visit Croptec or BP2017 to find out about Controlled Release Fertilizers (CRF).

Scott Garnett, from ICL Speciality Fertilizers, explains that the CRF technology is simple but highly effective. “The fertilizer granules have a special coating, which is essentially a semi-permeable layer that controls the release of fertilizer to the growing plant,” he says.

“This works in conjunction with the soil temperature, with more fertilizer made available as the soil warms up. If the temperature drops, the coating condenses and slows the flow of nutrients.

“As well as changing the way plants receive nutrients, CRFs can also help to provide a solution to issues that are often caused by improper management of traditional nitrogen programmes, such as leaching, volatilization and denitrification.”

Leaching

He explains that nitrates leaching into watercourses are a major concern for water companies. “They’re under pressure to meet the current drinking water standard for nitrates, of below 50g/l as NO3. Where this is exceeded, costly measures have to be implemented to ensure water is safe to drink,” says Scott.

So, in order reduce this issue, farmer collaboration with water companies, coupled with best practice and the use of technology such as CRFs, could provide the solution. This is because there will not be excess nitrogen in the soil, as it is only released when it is required by the plant.

Volatilization

Another problem often caused using conventional urea or ammonium fertilizers is volatilization of ammonia into the atmosphere, which not only leads to human health concerns, but can also be problematic for the environment.

However, Scott explains that CRFs can also minimise the occurrence of this. “Because of the unique coating on the granules, a greatly reduced volume of fertilizer is exposed to the air, for a considerably shorter time, reducing volatilization.”

Denitrification

Denitrification can also cause concern for farmers, because of the effect it has on the efficiency of the fertilizer in anaerobic conditions.

“Microorganisms in the soil strip any available oxygen from the nitrates, which are then lost as a gas into the atmosphere. This problem is heightened by wet conditions with compaction,” says Scott.

“Applying a CRF can alleviate this issue in two ways; because nitrogen is released slowly, there’s a decreased period in which the nutrient is in the soil before plant uptake, and as less applications are needed, compaction is reduced due to less machinery traffic on the field,” says Scott.

For more information please visit icl-sf.com/uk/explore/fruit-vegetables-arable-crops/ or visit the ICL stand at either Croptec or BP2017.