Granular Complex Compound Fertiliser (CCF) is a manufactured product which has all the nutrients in one granule of fertiliser. So if you have purchased a 23.4.13 + 7SO3 CCF, and having opened the bag you pick out one granule, that granule will have all four nutrients inside.
Left: Representation of a granular complex compound fertilizer. Right: How the finished product may look
Blended compound fertiliser, or blend, is not a manufactured product in the same way as a CCF. A blend is a mix of the nutrients; having opened a bag of 23.4.13 + 7SO3 and you pick out one granule, that granule will be either Nitrogen (N), or Phosphate (P), or Potash (K) or Sulphur (S).
Left: Representation of a blended compound fertilizer. Right: How the finished product may look
In one hectare of newly sown ley there could be as many as 6.5 million individual grass plants. To ensure maximum performance over the lifetime of the ley, it is essential that each plant is given the right balance of nutrients, every year, to ensure healthy growth and optimum survival. The analysis required will vary with the way the ley is to be used.
To understand why true granular compounds are so effective it helps to compare the number of individual granules of fertiliser in a compound, with the number an composition of granules in a blend. At a rate of 250kg/ha (2 bags per acre) a true granular 25.5.5 compound delivers about 10 million granules per hectare. Always remembering each granule contains N, P and K.
Using a blend to achieve the same analysis and depending on the raw materials used, there may only be 500,000 – 1 million individual granules per hectare of P and K. In other words, on average only 1 in 10 grass plants will receive P or K in close proximity.
Some plant nutrients move slowly through the soil and limiting Phosphate availability will result in lower yields for first cut silage and early grazing. Potash availability can also be affected, particularly if the soil is dry. Combining N, P, K and Sulphur in one granule gives every plant a chance.
In the examples below, spreading tests undertaken by Kverneland show that the nutrient analysis delivered to a given point by a blended fertiliser varies, depending on the quality of the blend, calibration of the spreader and the bout width.
The overwhelming conclusion from the Kverneland tests are you can set a well maintained spreader to spread most products accurately in terms of physical spread but a CCF always delivers nutrients more accurately and uniformly than a blend.
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