Fertiliser prices jumped by almost £20/t last month, according to September results from the Farmers Weekly/NFU inputs price monitor.

The online survey, based on actual prices paid by farmers (excluding VAT), found ammonium nitrate averaged £230/t last month, up from £212/t in August. But, there was a clear split in prices, with the cheapest AN reported at £209-215/t and the most expensive at £245-253/t.

“It appears that the lower band of prices submitted relate to product delivered in the last month rather than that purchased,” NFU inputs adviser Peter Garbutt explained. “Unfortunately, it appears as though last month’s Inputs Price Monitor prediction for October will shortly be realised with prices of circa £250/t.”

Phosphate (TSP) prices were also up last month, by about £17/t, to £335/t on average. But potash (MOP) prices fell by around £5/t to £310/t in September, largely due to the top-end range falling, suggesting that deals were still out there.

Red diesel prices were largely unchanged at an average of 50p/litre in September, with white diesel up almost 2p/litre to almost 99p/litre. The 1p/litre fuel duty rise that came into effect on 1 October meant a further increase could be expected this month, Mr Garbutt said.

There was a fairly even spread of prices paid for glyphosate, with the average coming in at £2.13/litre, down 46p/litre from August.

The Inputs Price Monitor relies on farmers submitting their prices every month. It’s quick and anonymous to do and the more results we receive, the more accurate the data.

• To take part in October’s IPM survey and view previous results, go to www.fwi.co.uk/IPM