Guideline Index

# Chapter 14: Calculating Rates and Costs

The financial benefit of applying the correct blend of fertiliser can be substantial. For example, a cost comparison of three options (each supplying 35 kg P/ha) is summarised in Table 14.3. This comparison clearly demonstrates the importance of the following:

1. Calculate nutrient requirements first – see Chapter 15.
2. Select fertiliser/s that supply the closest match of required nutrients, at the lowest cost. Table 14.3 Effect of fertiliser choice on total fertiliser cost when applying 35 kg P / ha over a 200 ha farm

This table highlights the potential savings (or potential extra cost) when working out a farm nutrient application strategy based on the P requirements. The cost of option 3 is \$14,807 less than option 1.

Options 1 and 2 would be more favourable if K and S were required in larger quantities. Option 1 applies P, K and S; option 2 applies less K than option 1; and option 3 applies less K and less S than option 1.

It is worth taking the time to do the calculations when deciding the fertiliser program on your farm.