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Slurry King’s Top 10 slurry tips - Tip No 4: Understand the science of slurry


Some farmers have an easier time of it than others when it comes to slurry management. We believe that slurry should be a valuable asset for all farmers.
Here is our fourth tip on how to take the hassle and smell out of slurry and turn it into a valuable asset.


Unless you are a chemistry geek the science behind slurry can be more than a little confusing.  Slurry contains several chemicals which not only have long names but are often referred to by more than one name.  Then there are the symbols for each chemical which bear no resemblance to the chemical name.

Despite this complexity it is important for a farmer to understand the science of slurry.  By understanding the science a farmer can make sure that they are making the best use of the nutrients in their slurry and not paying more for fertiliser than they need to. 

Most farmers are familiar with the term NPK but perhaps not all fully understand how to make NPK work best for them.

In simple terms NPK is a combination of

N for Nitrogen

P for Phosphorous

K for Potassium (also known as Potash)

NPK are the main nutrients of slurry and when used correctly, can fertilise crops and reduce (or even eradicate) the requirement for costly artificial fertiliser.

The main challenge stopping NPK reaching crops through slurry spreading is that NPK is not nicely mixed up in liquid slurry ready for farmers to spread and is not in a form that can be readily taken up by the plants.  As all livestock farmers know, slurry quickly separates into liquids (water & urine) and solid (faeces).   Unfortunately a large part of NPK (particularly the highly nutrient Nitrogen) is held in the solids part of slurry which is often wasted. 

The solids part of slurry can be wasted for many reasons.  It can be left behind in the slurry store (if slurry is not mixed properly before spreading) or it may not be digested in the soil for many reasons including not being washed or ploughed in, being washed away, being spread in the wrong weather or being spread at the wrong time of year.

The amount of NPK wasted in slurry solids is really high.  55% of nitrogen and 100% of Phosphorous are held in slurry solids.  (K or Potassium is largely unaffected as most is held in the liquid part).

Products like Slurry King are available to make more Nitrogen and Phosphorous available in  the form required by plants but a farmer needs to start by understanding the science of slurry.  Only when a farmer understands the science can they make the best, most cost effective, decisions for their farm. 

To find out more about how to turn your slurry into a valuable asset contact Sylgen Animal Health on 01559 370 222 email