Growers in Herefordshire will have to seek planning permission to use polytunnels after a landmark decision from the county council.
The council's cabinet voted unanimously last week to approve the new rules. The move, which means each field will be considered as a separate development, is expected to prompt hundreds of applications a year from the county's soft fruit growers.
Farmers with polytunnels in place are unlikely to be told to remove them this year, although some will be served with enforcement notices to prevent the structures becoming permanent after four years.
Local grower Anthony Snell slammed the decision, and raised the prospect of a legal challenge by the NFU.
"We've taken legal advice, and we've been told there are problems with the Herefordshire County Council position - they seem to have got confused over different types of polytunnel."
Though the decision was unlikely to affect soft fruit production this year, he added, it would add cost and worry for growers. "The majority of growers must get planning permission, otherwise the move is complete nonsense."
Growers also fear the council decision will encourage opposition to polytunnels across the country, but Phil Edwards, cabinet member for the environment, has told The Grocer that most have nothing to fear from the new regime.
"There won't be huge changes for growers, as the code of practice we used to use already required them to come forward to planners before putting up a polytunnel," said Edwards.
"As long as farmers complied with the voluntary code in the past, I wouldn't anticipate any problems."
However, he estimated as many as 16-20% of the polytunnels in the county had been planted by growers who had ignored the code. It was likely to take months before advice for growers was available, he added.