Thousands of farmers across Britain fear that they could experience the worst harvest in years after this month's relentless rainfall.

Less than a quarter of the harvest is in, compared with 80 per cent at the same time last year. The South West, the West and the North are the areas worst affected, but even in the South of England the harvest is running at least two weeks late. It will be another ten to fourteen days before householders will learn if they face higher prices for bread, biscuits, cake and flour.

Growers face an anxious wait to find out how much of their crops can be salvaged and what price they can expect to earn for them. Many are predicting heavy financial losses and some have already decided to reduce their seed plantings for next year. Fuel and energy prices are on the rise and the cost of fertiliser, £150 a tonne last year, is expected to be at between £350 and £400 a tonne this autumn - which means that many farmers will leave land fallow next season rather than risk the expense.

The main problem is with wheat. The best prices are paid for grain used in the manufacture of bread, earning a farmer £140 a tonne this year - still down on last year's bumper prices of £170 to £180 a tonne - but the rains have left some crops so wet that they will never reach this standard. Many farmers will be forced to sell their wheat as animal feed, at about £110 a tonne. This is also down on last year's price of £140 a tonne. Their losses are compounded because it costs about £15 a tonne to dry wheat.

Gary Lee, who farms 1,700 acres (690 hectares) at Poynings on the South Downs in West Sussex, said: “If you do the sums now the prospects for next year look very tight. We might have to leave some land fallow. But we have got to get the wheat in; that is the priority. The crops are so wet they contain more than 21 per cent moisture. You have to get it down to below 14 per cent for a chance of a good price.”

Jim Meadows, who farms the same acreage near Stratford-upon-Avon, Warwickshire, has abandoned his winter barley because the ground is so wet that his combine harvester gets bogged down. He said: “About 1,200 acres of my crop is wheat but I can tell you now I will not be planting that amount next year. It is just not profitable. I will be lucky to get £110 a tonne and I need £120 to £130 to make a profit.”

Guy Gagen, chief arable adviser at the National Farmers' Union, said: “Like everyone else, farmers are feeling the effects of rising costs, especially the cost of inputs like fertiliser and fuel. Some fertiliser manufacturers have been forced to demand payment before crops are sold, which means many farmers will be looking at cropping patterns, use of fallow land, and cutting back on planting crops that use the most fertiliser.”

Despite the gloom, millers are confident that if the harvest is brought in within 14 days there could still be a significant wheat yield of 16.5 million tonnes. Last year the crop totalled 13 million tonnes.

Simon Ingle, head of milling wheat at Grainfarmers, which buys 20 per cent of home-grown wheat, said: “Even with the problems of the weather I would say yields are up significantly, with 4 to 4.5 tonnes an acre. It is not uncommon to have a late harvest and unless it gets to a point where rain makes it impossible to harvest the grain, I am expecting a big crop.”

He said that wheat prices would fall because more crops have been grown around the world to meet the demand from new economies in India and China and because of good harvests in Australia and Argentina.

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