It is important to finish your grazing season off on a high, and spreading the right fertiliser will help you get the most out of your grass.
As we come to the latter end of the grazing season, the first thing that has to be assessed is the amount of phosphorus (P) and nitrogen (N) that farmers are allowed to spread during the last couple of weeks.
Farmers are obliged to operate within fertiliser N and P allowances in line with the nitrates regulations.
There are no changes to the N and P allowances for 2024, as announced by the Minister for Agriculture, Food and Marine, Charlie McConalogue.
This gives farmers a chance to bridge the gap for fodder deficits and get the most out of their grazing season for the rest of the year.
N and P allowance
P allowance is dependent on soil test results and the amount of concentrates the farmer feeds. It should be calculated to see how much more they can spread for the remainder of the year.
N allowances are somewhat more straight forward to calculate on most farms, as they are based on the stocking rate on the grassland area.
The N allowances per/ha based on grassland stocking rate are as follows:
Grassland stocking rate (kg/ha of org N) N fertiliser allowed (kg/ha) <130 114 131 – 170 185 171 – 210 254 >211 225
To calculate the amount of fertiliser you are allowed on your farm, multiply the amount of N allowed by the area of grassland to get your total fertiliser N allowed.
Autumn fertiliser
A fertiliser plan should be put in place to get accurate applications out on the grazing and silage ground in order to get the best out of the grass growth conditions over the coming weeks.
This year, it is particularly important to get out the maximum N and P you are permitted to spread, while also getting out an appropriate amount of potassium (K) and sulphur (S) where required.
K works very well at this time of the year, so there is an opportunity to apply K with fertiliser N for the next seven weeks. If you don’t have a P allowance, there are zero P products with N, K and sulphur (S) in them.
K should not only be used to boost your third cut silage, but used for the grazing block as well and products like 29-0-14 can help to replace K on paddocks that have been cut for silage or surplus bales.
For third cut silage, you should aim to apply at least 75kg/ha of N and keep it topped up with P, K, S through slurry or chemical fertiliser.
For your grazing ground, the aim should be to apply around 56kg N/ha from now to the middle of September as per Teagasc.
Front load N in August and target paddocks that have good soil fertility or that were recently reseeded to get the best response from your fertiliser, and the rate of spreading should be reduced for your swards with good clover content.
Making sure to maximise the amount of fertiliser you’re allowed spread from here to the end of the grazing season is crucial in getting the best out of your cows and building up fodder supplies for the coming winter.
The potential fodder supplies this winter can be turned around in the coming weeks by utilising your grass as best as possible.