The UK fruit and veg industry has come out in support of a glasshouse at risk of being thrown off course by planning regulators.

Later this month, Sussex-based Madestein UK, which supplies wholehead lettuce to Sainsbury’s and Waitrose, is due to appeal Chichester district council’s unexpected decision last March to refuse the planning application for a new 21-hectare glasshouse in Sidlesham.

The NFU said a positive outcome was important for the future of the British fruit and veg industry. Planning refusals could send a negative signal to the industry “when many farmers and growers are driven by market conditions and supply chain structure towards larger-scale production”, it said.

About 64% of fresh fruit and vegetables consumed in the UK were imported and there was a £6.5bn trade deficit in the sector, the union added.

The view was echoed by the West Sussex Growers Association, which voiced concern about the knock-on effect a failed appeal might have. Horticulture in the West Sussex coastal plain was estimated to be worth £500m in retail sales, the WSGA said.

“It would be a serious blow to horticulture in West Sussex,” said John Hall, a former president and chairman of the WSGA who currently works as a consultant for the organisation. “This could be about almost any of our members looking to find a new place.”

Madestein itself has stated in a report to Chichester council that it would struggle to meet demand if it does not get permission.

“Because of the operation of the category management system by retailers, the company risks losing not only additional sales but also its existing sales if competitors can supply 100% of the demand,” said Gerry Hayman, a horticultural consultant commissioned by Madestein.