Although April frosts are not unusual, the dip in temperatures follows the fifth warmest March since 1910 and plant growth is currently ahead of schedule.
NFU chief horticulture adviser Hayley Campbell-Gibbons said: “Soft fruit production is protected by polytunnels, which can handle frosts of up to minus two degrees, but a severe frost would still be dangerous, and the cooler than average temperatures will certainly slow down production.
“The biggest concern is outdoor fruit production – such as apple and pear orchards, and blackcurrants. Production is ahead of schedule in many parts of the country, which means trees are in full flower and very vulnerable to night frosts. A severe frost could significantly impact British fruit production.”
Across Europe damage seems to be widespread in Belgium and Germany but in The Netherlands it is more localised; some areas have major damage but some got off very lightly. Eastern European has seen heavy snowfall and temperatures dipping well below zero.
The general opinion in England seems to be that there is not too much damage but growers are still assessing the fruit trees and should have a better idea of any long term damage by the weekend.
"Frost is very different to a sudden hail storm, after a hail storm things tend to get worse as the season progresses but, after a frost, the trees and fruit tend to keep improving," explains Paul Abell Sales Manager at ABB Marketing, in Kent. "I have spoken to the seven growers who supply us here at ABB Marketing and although they caution that it is too early for the full picture, initial signs are that any damage is minimal, with most reporting no damage. Some are even saying that this cold spell has actually been beneficial, a sort of natural thinning of the buds on the trees."
However the effects of the night frost do seems to increase as you head further east into Kent.
John Simpson from Adrian Scripps, Tonbridge, Kent, said that the effects are variable with some growers having orchards with between 50 and 80% of flowers affected.
"We have had temperatures just below freezing, but even if some flowers are affected it may not mean a significant loss in actual crop. Long term effects are unknown at this stage, but there will probably little be effect on fruit numbers."
The forecast is for more nights of frost, then night temperatures will go up to 10-11 degrees.