Snow North Yorkshire
© UnknownSnow covers a field in North Yorkshire, with many crops affected

Months of heavy rain followed by extreme cold are set to hit harvests and push the price of the weekly shop up ever higher.

More than a quarter of winter wheat could not be planted last autumn because of waterlogged fields and attempts to catch up this spring have been hampered by frost.

But poor grain yields do not just affect the price of bread and biscuits.

Animal feed is 50% more expensive than 15 months ago, in turn increasing the cost of producing meat, milk and eggs.

Mother-of-three Sarah Tait is concerned. She has already seen her weekly bill rise from ยฃ80 to around ยฃ100 in the past 18 months or so.

She said: "It is a worry. It just means there will be other things we don't buy because we have to buy food and retailers have got you really because you have got to pay what the prices say."

Other crops including potatoes, tomatoes and sugar beet have also been delayed.

In the 12 months to February fruit has risen in price by almost 12%, vegetables are up 7%, meat costs 4% more and bread and cereals are 3% more expensive - all above general inflation, which stands at 2.8%.

On the Euston Estate in Suffolk crops like winter barley have struggled from the start after being sown in November rather than the end of September due to the weather.

Estate manager Andrew Blenkiron expects the late planting to have a 20% impact on yield.

He said: "There are areas of the field that we couldn't plant because it was so wet and usually we would try to work through the winter and try to patch it up, but there's still water lying in it in early April."

UK growers should also have planted 50% of their spring cereals by now but have in fact only managed to sow 15% due to the weather.

Shoppers are being advised by Richard Dodd from the British Retail Consortium not to be too worried.

He said: "Customers shouldn't panic about the impact on food prices of this weather, of course it's adding an extra pressure, but at the same time the cost of lots of key world commodities, things like wheat are actually coming down, and that's certainly balancing out any upward influences from weather.

"And of course retailing remains incredibly competitive so as the retailers battle it out for every bit of spending that is to be had from customers, they are doing all they can to protect customers from any effects."

But at the beginning of the year, Waitrose's managing director Mark Price warned the price increases in some commodities will be "massive".

And it will be some months before the full impact of the bad weather on crops becomes clear.