With fertiliser prices rising in excess of 30% compared to last year taking account of slurry and FYM applied to land is even more important to ensure that you do not use more purchase in-organic fertiliser than you need to. This should be coupled with up-to-date soil samples to ensure you target the slurry and FYM where it is most needed to reduce the requirement for purchased phosphate and potash.
The availability of the nutrients to the following crop from FYM applications does not vary that much regardless of the time of application. There is more variation however with slurry as the table below shows:
As the table shows the nitrogen available is highest from spring applications and lowest in summer and winter. The available phosphate and potash do not vary during the seasons.
To put this into more practical terms if you applied 2500 gallons per acre of slurry on grassland it would put on the following nutrients that are available to the crop:
On this basis in a normal grazing routine of applying 50 kgs / acre of 34.5%N fertiliser, which provides 17.25 kgsN per acre, you would be able to reduce this rate if slurry were applied to 21 kgs per acre in the spring and 30 kgs per acre in the summer. The potential saving on 100 acres equates to £770 per application of slurry, just for the Nitrogen, plus the benefits of P and K.
To discuss a fertiliser plan for your farm to ensure you maximise the use of nutrients from slurry, contact Phil Cooper who is FACTS qualified at firstname.lastname@example.org or your local FCG Office.