After an exceptionally dry April, a Norfolk farm is testing the financial viability of irrigating wheat crops to protect yields from our increasingly volatile weather.

North Norfolk farm contractor Kit Papworth began irrigating his wheat fields last Wednesday - the earliest he has ever needed to supply extra water for a crop which usually relies on April showers.

He is taking part in a national trial to assess the financial viability of this strategy - and he said the price paid for the grain had a big impact on whether wetting wheat pays.

"We are seeing some really significant yield increases, and some quality increases, from irrigating cereals," he said. "But these conversations are a lot easier when wheat is £180 per tonne like it is now.

"Last year, putting two inches of water on a crop of wheat has absolutely paid off, hands down. It was the single most important input other than nitrogen (fertiliser) last year.

"In the past we have just done 'quick and dirty' farm trials and picked up from yield maps that it was showing around two tonnes per hectare of yield increase for the last harvest, after a dry season.

"That is about £400 per hectare of increased yield at the moment because out-of-store wheat is £180-£200 right now, so at current prices that definitely pays.

"But on potatoes it pays even more, so do I irrigate wheat and risk running out of water for potatoes later in the season, or do I gamble and assume it is going to rain at some point?

"The pattern is we seem to be getting in Norfolk is these longer, wetter winters and then when it stops raining it does not re-start again. So we need to know what the water deficit is when we need to irrigate cereals, and the best timing.

"It is a practical balance and we need to pull all that data together to make the right decisions."

Eastern Daily Press: North Norfolk farmer Kit Papworth began irrigating his wheat crops on April 28North Norfolk farmer Kit Papworth began irrigating his wheat crops on April 28 (Image: Kit Papworth)

Teresa Meadows is a knowledge exchange manager for the AHDB (Agriculture and Horticulture Development Board), which is running the series of farmer-led trials across the East of England.

She said about 10pc of UK wheat yield is lost on average due to insufficient soil moisture - with that figure rising much higher in the driest years.

Economic modelling of milling wheat grown on a sandy loam soil in the East of England suggests irrigation can pay – but only where existing equipment and "unused" summer water was available did the approach bring reasonable returns.

"Widespread adoption of wheat irrigation is likely to be many years off, if it ever happens at all," she said. "In a severe drought year, competing priorities are likely to rule out the option, in most situations.

"However, knowing the potential and the limitations associated with the technique will help build knowledge resilience. Should the wheat price drive higher, available soil moisture fall lower, and resource (infrastructure, skills and staff) be in place, such an understanding is not a bad thing to possess."