Growers fear a public backlash will follow the judgment last month against Tuesley Farm in Surrey, which was told to remove temporary polytunnels because it did not have planning permission.
"If we are restricted there will be strawberry shortages, and so prices will be higher or fruit will be sucked in from overseas," said Laurence Olins, chairman of British Summer Fruits. "The worst-case scenario is that you will never be able to use polytunnels again. No one is going to grow soft fruit without polytunnels."
There is disagreement as to whether the ruling sets a precedent or only applied in Tuesley's planning case.
If other councils follow suit and crack down on polytunnel use, the growing season would be cut to six weeks and put crops at the mercy of British weather. "There will be a lack of continuity of supply, meaning we'll see empty or full shelves based on the weather," said John Owens of Angus Soft Fruits.
Most businesses would stop growing soft fruit because it would be unviable for just six months of the year, especially when competing with Spanish growers using tunnels. "If I couldn't use polytunnels my business would cease to function," said grower John Boyd of Beaulieu in Hampshire. "Even last summer there were still periods when polytunnels were indispensable."
The industry said it had to use polytunnels responsibly to keep the public on side. One idea is to issue a licence instead of going through lengthy planning procedures.
The rules for farm assurance have also been updated for 2007 to spell out how to use polytunnels considerately, including removing them when the crop is over and rotating the areas under plastic, said NFU horticulture board chairman Richard Hirst.