Growers of Jersey Royal potatoes have been in a race against time to salvage the remainder of this season's crop following heavy rainfall on the island.

Producers have worked around the clock over the past week to remove Jersey Royals from the island's 4,300 acres of potato fields, which had been either swamped with mud or left under water following a prolonged period of rain. About 40% of the island's annual production was still in the ground when the rain hit.

A Tesco spokeswoman said that availability was now back to 100% in store, and Jersey Royals had been added to the retailer's Fruit & Veg Pledge.

The Jersey Royal market is worth £35m annually, with the variety representing 75% of all UK potato sales during the March to June season.

A clean-up operation dubbed Save Our Spuds was launched by Tesco and its grower suppliers on the island to get the remaining crop into stores before the season's end in three weeks.

Twenty tractors were brought to the island to help tow the harvesting equipment already in place, while growers The Jersey Royal Co provided 550 people to help. "This rainfall is potentially devastating for Jersey's agricultural industry as Jersey Royals are by far the island's most important export crop," said Tesco potato buyer Paul Smith.

Jersey Royal Co managing director Tom Binet added: "I've been growing Jersey Royals here for 35 years and have never known anything like this - you just don't expect so much rain at this time of the year."

Despite the heavy May rainfall, crops elsewhere in the country were undamaged and better weather in the early part of June had allayed fears of major crop losses, said Richard Hirst, chairman of the NFU board for horticulture.

However, it had been a close call. "There was quite a lot of rain about and if we'd had any more we could have started to see a repeat of last year," Hirst said.