Custom blending for better fertiliser decisions
Blended fertilisers are the most popular type of fertiliser being used in production as they meet all the crops nutritional requirements in a one-pass application.
Incitec Pivot offers more than 900 standard blends, with a further 3,600 custom blends generated after requests from Nutrient Advantage® Advice accredited advisers or from Incitec Pivot distributors.
This range of blends allows for almost any crop nutritional requirement to be met, with new custom blends continually being created to match nutritional needs of crops and avoid the under or over application of nutrients.
Access to custom blending and to a comprehensive range of fertiliser blends allows the nutrients in your fertiliser investment to match crop requirements.
Follow this link to view the full Blending Guidelines.
Choosing the right fertiliser
Most individual fertilisers contain only a specified limited number of essential nutrients and are known as ‘straights’. As an example, Urea contains nitrogen with an analysis of 46 per cent and Muriate of Potash contains potassium with an analysis of 50 per cent.
There are only a select number of straights available. They must typically have several characteristics, including water solubility and plant availability as well as their cost effectiveness when compared to other fertilisers.
For instance, to meet a combined nutrient requirement like that of nitrogen, phosphorus, potassium, sulphur, magnesium and a trace element requirement, fertiliser ‘straights’ have to be 'mixed' or 'blended' to match these multiple plant nutritional demands in one fertiliser product often referred to as “one-shot” blends.
This allows for the efficiency, cost benefits, timeliness, reduced trafficking and convenience of a single-pass application.
To apply a dollar value to such blend scenarios, let’s look at a hypothetical situation for a crop by assuming a soil test shows a requirement for 160 kg/ha of nitrogen, 15 kg/ha of phosphorus and 100 kg/ha of potassium.
If only a limited number of fertiliser blends were available in a supplier’s range, a blend with an analysis of 25 per cent nitrogen, 3 per cent phosphorus and 18 per cent potassium applied at 640 kg/ha would most closely match the nitrogen requirement, as mentioned above. However it would over apply both phosphorus and potassium.
Using fertiliser costings* this equates to, on a per unit of nutrient basis:
- $1.50 per unit of nitrogen as urea
- $4.70 per unit of phosphorus as DAP
- $2.40 per unit of potassium as muriate of potash
Applying the above fertiliser blend at 640 kg/ha, would lead to an over-application of phosphorus and potassium by 4 and 15 kg/ha respectively This alone equates to an additional fertiliser cost of over $54/ha, compared to using a custom blend to precisely match the soil test determined nutrient requirement of 160 kg/ha nitrogen, 15 kg/ha phosphorus and 100 kg/ha potassium.
It is easy to focus on the price of a tonne bag of fertiliser but as this example shows significant financial gains are to be made by applying only the required nutrients and hence making better fertiliser decisions.
Speciality products like compound fertilisers can also be used. Compound fertilisers differ from blends as there are multiple nutrients contained within every granule. Examples of compound fertilisers include Nitrophoska® Special fertiliser and the range of Incitec Pivot's Granulock® fertilisers. Compound fertilisers also give the potential for a more uniform nutrient application.
Custom blends and compound fertilisers can be sourced through an Incitec Pivot Fertilisers distributor and delivered on-farm, generally within 24 hours of ordering.
Blends are available in a wide number of straight fertiliser combinations, however guidelines do exist as to which ingredients can or can not be blended together based on their physical and chemical compatibilities and also agronomic considerations.
Not all fertilisers are compatible with each other. For example, Urea and Cal-Am® are incompatible in dry blends, and if blended will rapidly absorb moisture from the air.
There are also minimum and maximum limits to the quantities of some ingredients in blends. At very low addition rates, blend uniformity is compromised, and upper limits are placed on some ingredients due to operational constraints that relate to compliance with Dangerous Goods, Hazardous Substances or Poisons legislation.
Also, be aware that uniformity of blend quality is best achieved when all of the ingredients are closely matched in size, to minimise segregation during handling.
Once agronomic and blend compatibility requirements are fulfilled, custom blends are as easily accessible as conventional blends and comparably priced on a per unit basis to other Incitec Pivot Fertilisers products.
Making the right choice
Before choosing the ‘right’ fertiliser, growers should perform a soil analysis, look at the nutrients required and consider the various nutrient forms, convenience, application method, availability, nutrient use efficiency and price when making a fertiliser decision.
Nutrient Advantage accredited agronomists can help growers with this decision by using a combination of local knowledge and recommendations through the Nutrient Advantage Advice (NAA) software system.
NAA allows agronomists to provide recommendations based on current and previous soil test results, local conditions and varying farm management practices.
Incitec Pivot’s Nutrient Advantage® Laboratory can help growers to cost-effectively manage their fertiliser requirements with comprehensive testing for all essential nutrients, plus other soil chemical and physical properties.
All testing services provided by the Nutrient Advantage laboratory include the added benefits of reliability and credibility derived from the independent National Association of Testing Authorities (NATA) accreditation and Australasian Soil and Plant Analysis Council (ASPAC) certification.
To arrange a soil test to determine crop nutritional requirements or create a custom blend, contact your local Nutrient Advantage Advice accredited adviser or your nearest Incitec Pivot Distributor.
* Figures based on mid-May 2009 prices. RRP $/t bags, ex GST and excluding freight delivery costs to farm.