PLANNING AHEAD Planning ahead should help lessen the impact of the hike in fertiliser prices in both the short- and long-term. Dairy Farmer reports.
Options to reduce fertiliser costs
F
armers are going to have to accept a growing season with significantly higher fertiliser prices, but there are ways to reduce fertiliser usage to bring down costs without necessarily reducing performance, according to Promar International. Promar consultant Caroline Groves says: “We have seen a perfect storm for fertiliser prices with a number of factors combining globally to push them higher. “Ammonium nitrate [AN] prices are now £1.38/kg compared to £0.63/kg last year. Urea prices have also risen significantly at close to £1.17/kg. Phosphate has increased from £0.54/kg to £1.02/kg, while potash is running at £0.65/kg, up from £0.41/kg.” Ms Groves says the consequences at farm level could be marked. For the average dairy herd recorded through Promar’s Farm Business Accounts service, the spend on fertiliser last year was £17,600, but next year this will be £36,800 if usage rates remain unchanged. “To put this in context, these
herds have 240 cows with an average 9,000 litres/cow. This increase works out at £80 per cow. “Assuming no change in milk price, they will need to produce 64,000 litres more, 266 litres/cow. Alternatively, they will need to carry an additional 7.2 cows, just to cover the increase in fertiliser costs. “This is why it is important for businesses to review their fertiliser policy now and to identify any economies and efficiencies which can be made.” Analysis She advises that the starting point is getting soil analysed and recalculating fertiliser requirements based on soil indices. She says it is important to pay attention to pH, as correcting this is a cheap way to make better use of applied fertilisers. She says: “Many farms could take a P and K holiday on some fields, particularly those which have previously had high applications of slurry or muck. If indices are high, savings can be made. “Do not buy your usual compound
It is important for businesses to review their fertiliser policy now and to identify any economies and efficiencies CAROLINE GROVES
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just because this is what you always do. You might be able to replace it with a difference formulation or straight nitrogen [N]. Look at exactly what is needed and build a purchasing plan around this rather just buying the same as last year.” She advises looking at which source of N is the most cost-effective, but to take account of wastage. At £1.17/kg N, urea looks a good buy, but she says a considerable proportion will be hydrolysed and lost. When this is taken into account, the cost per kg actually available to the plant will be very similar to AN. “One option is to move to a form of urea which includes a urease inhibitor to give more time for the N to diffuse into the soil. Inhibitors provide emission reductions of 40% for liquid urea AN and 70% for solid urea. Although more expensive than straight urea, it will work out the best price per kg applied.” Relative value The relative value of slurries and manures will increase this year too, making it vital that the nutrients they supply are fully accounted for in any plans. Covering field heaps and slurry lagoons will reduce losses, leaving more nutrients to be spread. Simply allowing a crust to develop will also reduce wastage in lagoons. “When spreading slurry in spring, use a trailing shoe or shallow injection to increase nutrient retention. This could save the equivalent of 20kg N/hectare compared to a splash plate and reduce purchased N costs by £27.60/ha at current prices. “Look to spread manures under cool conditions with low wind, possibly spreading in the evening.
Plough any manures in as quickly as possible, as reductions of 60-90% in ammonia emissions and lost nutrient value can be achieved when manures are incorporated rapidly.” Ms Groves says there is still time to plant green crops into maize and cereal stubbles. Cereals, grasses, legumes and brassicas can all be used and will reduce nutrient leaching and increase retention with the nutrients available when the crop is ploughed in. She advises precision of fertiliser application will be key, particularly recommending getting fertiliser spreaders calibrated to make sure all fertiliser is spread where it needs to be. Assess fields carefully, as many will have less productive areas where fertiliser could be reduced. GPS yield data systems can give valuable information on how fields yield, which can be used to inform fertiliser application decisions. Challenge the rate to be applied on all swards, particularly older, less productive swards and make sure the N applied will deliver the best return. “Finally, in the long-term, review the productivity of every field over the first half of the season and consider reseeding or sward improvement through slot seeding.
NOVEMBER 2021 15/10/2021 09:25
