The Organic Research Centre (ORC) admitted some areas of the market were under pressure but that did not mean "the end" for organic growing and farming.
A representative said the 1990s recession saw growth in organic sales level off, but not reverse: "Once the recession passed, the organic sector moved back into double-digit growth."
But he said growers toying with converting to organics should think twice. Conventional input prices had reached record levels.
The comments followed Mintel research that found almost half of all organic shoppers would cut back or give up buying organic food next year. The market is worth £1.6bn.
"After five years' impressive growth, attitudes are changing and sales are set to slacken off," said director of retail and finance Richard Perks.